TREES OF TREES:
A curriculum for teaching high
school students about the phylogeny
of gymnosperms
Margaret Connolly
University of Maine
INTRODUCTION TO THE
GYMNOSPERM PHYLOGENY CURRICULUM
This unit is designed for high school biology students. The unit is divided
into four main sections: Section 1 – Introduction to Phylogenetics;
Section 2 – Gymnosperm Case Study; Section 3 – Putting it all Together;
Section 4 – Sharing your Knowledge. The entire unit should take about a
month to complete. It should be integrated into the students’ study of
evolution and genetics. This unit does not cover all aspects of phylogenetics
or gymnosperm evolution, but it attempts to provide students with a quality
introduction to those topics.
Goals of the unit:
This unit is designed to bridge the gap between students’ knowledge and
understanding of evolution and the environment that they see around them.
Many students may have a difficult time applying the concepts they have
learned about DNA, heredity, and evolution to the actual world. A
disconnect may exist between what is learned in the classroom and what is
seen in the environment. This unit will allow students to explore an
interesting and useful group of organisms, the gymnosperms, and to form
hypotheses regarding their evolution to the state in which they exist today.
Students will gain an appreciation of the roles of morphology, molecular
biology, and biogeography in the identification and classification of
organisms. In addition, this unit encourages the sharing of knowledge with
the students’ peers, families, and the community through the creation of
field guides and interpretive tours of local areas. This will foster an
appreciation of local resources and will introduce opportunities for outdoor
recreation and education. The students’ exploration, study, and
interpretation of local areas will develop in the students a sense of
ownership and responsibility for the local environment.
Rationale:
In order to understand the present state of organisms, we must understand
their past. And in order to understand their past, we must understand their
evolutionary history. Current investigations into the evolutionary histories
and relationships of organisms focus on the integration of data from a
variety of sources such as morphology, biogeography, and molecular biology.
This unit introduces students to the many fields of science that must be
explored in order to form a plausible hypothesis of an organism’s
evolutionary path.
Evolutionary history and relationships among organisms can have farreaching effects. They can potentially lead to the discovery of new
medicines, new agricultural or horticultural products, and may influence
conservation strategies. The concepts and skills learned in this unit are not
limited to an ecological context. Collection and analysis of data, forming
hypotheses, and sharing information are fundamental to creating wellrounded students in any discipline. Additionally, in an increasingly indoororiented society, this unit encourages students to leave the traditional
classroom setting and to study organisms in the field.
PRIOR KNOWLEDGE
Ideally, this unit will be commenced after students have a firm grasp of the
following concepts (from Life Science standards in the National Science
Education Standards - NSES):
THE MOLECULAR BASIS OF HEREDITY
!
!
!
In all organisms, the instructions for specifying the
characteristics of the organism are carried in DNA, a large
polymer formed from subunits of four kinds (A, G, C, and T). The
chemical and structural properties of DNA explain how the
genetic information that underlies heredity is both encoded in
genes (as a string of molecular "letters") and replicated (by a
templating mechanism). Each DNA molecule in a cell forms a single
chromosome. [See Content Standard B (grades 9-12)]
Most of the cells in a human contain two copies of each of 22
different chromosomes. In addition, there is a pair of
chromosomes that determines sex: a female contains two X
chromosomes and a male contains one X and one Y chromosome.
Transmission of genetic information to offspring occurs through
egg and sperm cells that contain only one representative from
each chromosome pair. An egg and a sperm unite to form a new
individual. The fact that the human body is formed from cells
that contain two copies of each chromosome--and therefore two
copies of each gene--explains many features of human heredity,
such as how variations that are hidden in one generation can be
expressed in the next.
Changes in DNA (mutations) occur spontaneously at low rates.
Some of these changes make no difference to the organism,
whereas others can change cells and organisms. Only mutations in
germ cells can create the variation that changes an organism's
offspring.
BIOLOGICAL EVOLUTION
!
Species evolve over time. Evolution is the consequence of the
interactions of (1) the potential for a species to increase its
numbers, (2) the genetic variability of offspring due to mutation
!
and recombination of genes, (3) a finite supply of the resources
required for life, and (4) the ensuing selection by the environment
of those offspring better able to survive and leave offspring.
[See Unifying Concepts and Processes]
The great diversity of organisms is the result of more than 3.5
billion years of evolution that has filled every available niche with
life forms.
MEETING STANDARDS
This unit will cover the following concepts (from the Life Science standards
in the NSES):
!
!
!
Natural selection and its evolutionary consequences provide a
scientific explanation for the fossil record of ancient life forms,
as well as for the striking molecular similarities observed among
the diverse species of living organisms.
The millions of different species of plants, animals, and
microorganisms that live on earth today are related by descent
from common ancestors.
Biological classifications are based on how organisms are related.
Organisms are classified into a hierarchy of groups and subgroups
based on similarities which reflect their evolutionary
relationships. Species is the most fundamental unit of
classification.
This unit will address the following additional standards (from the Science
as Inquiry standards in the NSES):
UNDERSTANDINGS ABOUT SCIENTIFIC INQUIRY
!
!
!
Scientists usually inquire about how physical, living, or designed
systems function. Conceptual principles and knowledge guide
scientific inquiries. Historical and current scientific knowledge
influence the design and interpretation of investigations and the
evaluation of proposed explanations made by other scientists.
[See Unifying Concepts and Processes]
Scientists conduct investigations for a wide variety of reasons.
For example, they may wish to discover new aspects of the
natural world, explain recently observed phenomena, or test the
conclusions of prior investigations or the predictions of current
theories.
Scientific explanations must adhere to criteria such as: a
proposed explanation must be logically consistent; it must abide
by the rules of evidence; it must be open to questions and possible
modification; and it must be based on historical and current
scientific knowledge.
!
Results of scientific inquiry--new knowledge and methods--emerge
from different types of investigations and public communication
among scientists. In communicating and defending the results of
scientific inquiry, arguments must be logical and demonstrate
connections between natural phenomena, investigations, and the
historical body of scientific knowledge. In addition, the methods
and procedures that scientists used to obtain evidence must be
clearly reported to enhance opportunities for further
investigation.
Section
1 – Introduction to
Phylogenetics
Questions to Investigate
· What is a phylogeny?
· Why should we care
about phylogenetics?
· How are phylogenetic
trees created?
2 –Gymnosperm Case
Study
· How do we use molecular
data, biogeography, and
morphology in
phylogenetics?
· What are gymnosperms
and conifers?
· How can we study
gymnosperms in the field?
General Objectives
Correlation to
Maine Learning
Results (Science
and Technology)
· understand the relationship
between natural selection,
molecular evolution, and the
present state of organisms
· have a working knowledge of
key terms associated with
creating phylogenetic trees
· appreciate the roles of
biogeography, morphology, and
molecular biology in
phylogenetics
A1, D1, D2, F6
· understand what defines
gymnosperms (and conifers,
more specifically)
· be able to identify local
gymnosperms through field
and classroom study
· collect and present data on
local gymnosperms
A2, J1
Correlation to
the Revised
Maine
Learning
Results
E1, E4, E5, C1,
D2
B1, E1, E5
3 – Putting it all Together
4 – Final Project - Sharing
your knowledge
How can we use our
knowledge of
gymnosperms and
phylogeny to reconstruct
the evolutionary history
of gymnosperms?
· How can we share our
knowledge of
gymnosperms with others?
· map morphological and
biogeographical data onto a
phylogenetic tree
· analyze current hypotheses
of gymnosperm phylogeny
J1,J2, J3, K1, K3, B1, C1
K6
· work cooperatively to create
a field guide to local
gymnosperms and/or create an
educational tour of a field site
L2, L3, L4, L7
C1
LESSON FORMAT
Most activities provided in this unit are divided into the following sections
(adapted from WOW! The Wonders of Wetlands):
Summary
Gives a brief description of the main question to be investigated during the
lesson.
Objectives
Describes the qualities or skills students should possess after participating
in the activity.
Materials
Lists supplies needed to conduct the activity and describes how to prepare
materials prior to engaging in the activity.
Setting
Suggests where the activity would best take place.
Duration
Gives a suggestion of how long the class should spend on a lesson. In many
lessons, the level of student knowledge and interest may determine how
much time should be spent on the lesson.
Key Terms
Lists terms that are probably new to the students’ vocabulary. It is
essential that the students gain an understanding of the meanings of these
words in order to discuss the topics presented in the unit.
Making Connections
Describes the relevance of the lesson and its contents to the students’ lives
and presents rationale for conducting the lesson.
Background
Provides relevant information about the lesson’s content or teaching
strategies.
Procedure
Warm Up
Gets students ready for the activity. It may suggest readings or questions
for students to consider before beginning the activity.
The Activity
Consists of a step-by-step procedure of the activity. Some activities are
further divided into parts or sub-activities.
Wrap Up
Closes the lesson and provides opportunities to assemble vocabulary, build
bulletin boards, and review concepts learned during the lesson.
Assessment
Presents assessment strategies that relate to the activity objectives.
Extensions
Provides additional activities for further investigation into concepts
addressed in the activity. (This section may not be present in every lesson).
Resources
Lists selected references that provide additional background information.
(This section may not be present in every lesson).
SECTION 1
Introduction to
Phylogenetics
INTRODUCTION TO PHYLOGENETICS
Summary
practical applications of the concepts
they have learned.
This lesson is designed to introduce
students to the field of phylogenetics
and to provide background information
on what phylogenetics is, some of its
applications, and some key terms.
Background
Please refer to the Introduction to
Phylogenetics reading for background
information on phylogenetics.
What in the world is phylogenetics…and
who cares?
Objectives
Students will:
· become aware of the field of
phylogenetics
· be able to define the terms
phylogenetics, phylogeny, and taxa
· be able to name one or more
applications of phylogenetics
Materials
· photocopies of the Introduction to
Phylogenetics reading
Setting
Classroom
Duration
45 minutes
Key Terms
· taxa (singular = taxon)
· phylogenetics
· phylogeny
Making Connections
Students should have already studied
the basic principles of genetics and
evolution. Learning about phylogenetics
will introduce students to
Procedure
Warm Up
Ask students to describe what they
think phylogenetics is. Have students
think about the pieces of the word:
phylo (tribe or race) + genetics; have
students briefly discuss their own family
trees and make a sketch of the
connections among the members of their
biological families.
The Activity
1. Provide students with a copy of the
Introduction to Phylogenetics reading
and discuss the reading with them
2. Have students define the key terms
(taxa, phylogenetics, phylogeny).
3. Faciliate a discussion of the reading.
Make sure that students understand the
main concepts
Wrap Up
Start a “word wall” that will include all
key terms from the unit. The wall can
be set up in two columns: one column
provides the key term, while the other
provides the definition. The terms and
definitions can be written in large print
on an index card. As the word wall
grows, you can use it for vocabulary
quizzes or other activities.
Assessment
Have students:
· define the key terms by starting the
word wall
· make a list of several applications of
phylogenetics
Extensions
Have students find other examples of
phylogenetics in action.
Resources
Understanding Evolution:
http://evolution.berkeley.edu
INTRODUCTION TO PHYLOGENETICS
What in the world is a PHYLOGENY…and who cares???
If someone were to ask you what the relationship between pine trees, spruce
trees, and tulips is, you could probably say pretty confidently that pines and
spruces are more similar, or more closely related, to one another than either
one is to tulips, right? But how do you know that? You could answer by
saying that pine trees and spruce trees are tall trees that have needle-like
leaves and tulips are herbaceous plants that definitely don’t have needle-like
leaves. Or you might say that pines and spruces are evergreens, while tulips
are not. Or you might just say that pines and spruces are sometimes used as
Christmas trees and you’ve never seen a tulip as a Christmas tree. You are
able to answer this question using pretty basic pieces of evidence that you
have observed in the morphology and physiology of the plants.
But now what if someone asked you about the relationship between pines,
spruces, firs, and hemlocks? These trees are all in the Pine Family
(Pinaceae), so they are all pretty closely related. But is a fir more similar to
a spruce or a hemlock or a pine? Why? You might not be able to answer this
question simply by looking at these different trees. You might have to
consider where in the world they grow, how long they live, what functions
they serve in the environment, what eats them, etc.
And now what if someone asked you about the relationships between a red
pine, white pine, jack pine, and pitch pine? You might now have to consider
the morphology, physiology, biogeography, and molecular biology of the
plants. You may be able to make a hypothesis about how these species are
related by comparing sequences of DNA.
The branch of science known as phylogenetics deals with the types of
questions that you were just asked. Phylogenetics focuses on discovering,
understanding, and piecing together the phylogenies of organisms. Simply
put, a phylogeny is an evolutionary history of something. That “something”
could be a particular species of beetle, or all of the different species of sea
cucumbers, or maybe all of the genera in the Pine family. The groups that
you are investigating are called taxa (singular, taxon). In the example of a
phylogeny of all of the genera within the Pine family, Pinus (the pines) is one
taxon, Picea (the spruces) is another taxon, Abies (the firs) is another
taxon, and so forth. In the example of studying the phylogeny of all of the
different species of sea cucumbers, each species would be called a taxon.
When phylogeneticists study a group of organisms, they make detailed
investigations into the morphology, biogeography, chemistry, physiology, and
molecular makeup of those organisms. In other words, the scientists find
out everything they can about what the organisms look like, where they live
and how they ended up there, how they function, and what secrets their
DNA contains. These investigations may require the scientists to study the
organisms in the natural environment, under microscopes, preserved as
fossils, or even as sequences of DNA.
Phylogeneticists use the information that they gather to create a “best
guess” of how an organism evolved into what it is today and how it relates to
other organisms. When dealing with phylogenetics, it is important to
remember that scientists make an educated guess as to how organisms
evolved. They can use evidence from DNA, fossils, biogeography, etc, but no
one will never truly know precisely how organisms evolved. Thus, phylogenies
are hypotheses of evolutionary history.
What can we do with phylogenetics???
So what’s the point of all this? Who cares about phylogenetics?
Those are good questions.
Imagine making a family tree of your biological family. It would show the
relationships between you and your siblings, your parents, your aunts and
uncles, cousins, grandparents, etc. If you became ill and needed a bone
marrow transplant, who would the doctors first consider to be an eligible
donor? Your neighbor down the street? Your dentist? No – the doctor
would think about your family tree and would suggest that your closest
relatives would be the most likely to be a match. The doctor would probably
test your siblings, then your parents, and so on, up the family tree. The
same concept can be applied to phylogenies of organisms. Here is an example
provided by the University of California Museum of Paleontology:
“Phylogenies also allow us to generate expectations about the characteristics
of living organisms that we have not yet studied. For example, scientists
discovered that the Pacific Yew produces a compound called taxol that is
helpful in treating certain kinds of cancer, but it was difficult and expensive
to get enough of the compound out of the tree to make its use broadly
feasible. However, based on the evolutionary relationships among yew
species, biologists expected that close relatives of the Pacific Yew might
produce similarly effective compounds. Happily, they were right! They
discovered that the leaves of the European Yew contain a related compound
that can also be used to efficiently produce Taxol. Taxol is now widely
available for cancer treatment.”
Pacific yew
European yew
http://evolution.berkeley.edu/evolibrary/article/0_0_0/phylogenetics_12
Here are a couple of other examples of how we can use phylogenies.
· You can use phylogenies to make predictions about fossils:
“Scientists used to think that whales' ancestors were now-extinct
carnivores called mesonychids. However, based on recent findings, scientists
have hypothesized that whales are actually more closely related to hoofed
mammals like hippos and ruminants such as cows and giraffes.
This hypothesized phylogeny leads us to predict that ancient whales should
share some characters with their close relatives. The close relatives of
whales have a type of ankle called a double pulley ankle, so we would expect
that ancestral whales would also have a double pulley ankle.
And in fact, recent fossil discoveries have borne out that prediction.
Scientists found ancient whales with hind legs and pelvises: these whales had
the same kind of double pulley ankle bone that modern pronghorns, camels,
cows and hippos have.
Compare the ankle bones of the two ancient whales on the left and right (the
specimen on the right is missing some bones) and those of a modern
pronghorn (center). Notice the double pulley structure boxed on all three.”
http://evolution.berkeley.edu/evolibrary/article/0_0_0/phylogenetics_10
· You can use phylogenies to learn about the evolution of complex
features:
“Reconstructing ancestral characters can help us understand how a complex
feature evolved. For example, the cichlid fish shown below vary in shape,
color, and striping patterns.
Researchers reconstructed the phylogeny of these fish based on molecular
data, then mapped striping patterns onto the phylogeny. Scientists used
parsimony (the practice of choosing the simplest scientific explanation that
fits the data) to infer the probable pattern of the ancestral fish. The
resulting phylogeny shows how these complex patterns evolved in different
lineages.
This technique helped biologists figure out that evolutionary changes in
cichlid striping pattern seemed to be related to ecological shifts — not
sexual selection. Similar techniques have been used to understand, for
example, how birds evolved the ability to fly and how tetrapods evolved to
live on land.”
http://evolution.berkeley.edu/evolibrary/article/0_0_0/phylogenetics_11
These are just a few examples of the many uses of phylogenies.
PHYLOGENETIC TREES
Summary
What does a phylogeny look like?
Students learn that a phylogenetic
tree is a visual representation of
evolutionary relationships. Using
an imaginary organism, the grillo,
students are introduced to
vocabulary used in describing
phylogenies.
Objectives
Students will:
· understand how a tree
represents evolutionary
relationships among taxa
· understand the terms common
ancestor, sister taxa, clade, node,
branch, tree, parsimony
Materials
· photocopies of the Phylogenetic
Trees reading
· photocopies of the Grillo
Evolution handout
· photocopies of the Parsimony
reading
· photocopies of the Another
Example of Parsimony reading
Duration
60 - 80 minutes
Setting
Classroom
Key Terms
· tree
· common ancestor
· sister taxa
· clade
· node
· branch
· parsimony
Making Connections
This lesson eases students into the
language of phylogenetics. Simple,
imaginary examples of evolution
allow students to explore the
structure of and concepts behind
phylogenetic trees. The skills they
learn in this lesson will be used
later in the unit.
Background
Please refer to the Phylogenetic
Trees reading and the
Parsimony reading for information.
Procedure
Warm Up
Hold a short discussion about how
the students think that
phylogenies are visually displayed.
Do they look like our family trees?
Are there any in the students’
textbooks? You can refer back to
the Introduction to Phylogenetics
reading for some examples of
trees.
The Activity
Part I – Building a tree
1. As a class, read the
Phylogenetic Trees reading. You
should help the students to
understand the concepts described
in the grillo evolution example by
drawing trees on the board and
explaining concepts.
2. Pass out the Grillo Evolution
handout. As a class or individually,
students should label key terms on
the handout. (example: label the
nodes, branches, circle groups of
sister taxa, etc.) Hint: If the
students are having trouble
understanding the concept of a
clade, physically cut branches of
the trees.
Part II – Using parsimony
1. Have students read the
Parsimony reading
2. Discuss the concept of
parsimony and ensure that
students understand how it
affects the grillo evolution
example
3. Have students read and
understand Another Example of
Parsimony if they need more
practice understanding parsimony
Wrap Up
Add the key terms to the word
wall
Assessment
· Collect students’ Grillo Evolution
handouts
· Review key terms and add them
to the word wall
Extensions
Encourage the students explore
the Understanding Evolution
website
(http://evolution.berkeley.edu)
Resources
Understanding Evolution:
http://evolution.berkeley.edu
PHYLOGENETIC TREES
What does a phylogeny look like???
A phylogeny can be drawn out in a diagram. There are several terms for
these diagrams (cladograms, evolutionary trees, phylogenetics trees), and
they are all slightly different. But to keep it simple here, we will just refer
to them as trees. These trees are made after the data from the various
sources discussed in the previous lesson have been gathered and analyzed.
There are actually computer programs that take your data and build the
tree for you. But it is helpful to try to build one (a fairly simple one) by
hand to really understand what everything means. There is a fair amount of
new vocabulary associated with these trees.
To learn about making a tree, we will use an imaginary group of organisms,
called the grillos. Today, there are 4 species of living grillos, called the blue
grillos, the red grillos, the brown grillos, and the black grillos. They look like
this:
blue grillo
red grillo
brown grillo
black grillo
Scientists have studied the habitats of these 4 grillo species, they know
what they eat, what they look like, and they have analyzed their DNA. From
all of this information, we know that blue grillos and red grillos have
triangular bodies. Their DNA is very similar and they are found living
relatively close to one another in North America. However, there are some
differences between the two (for example, the blue grillo has blue feet
while the red grillo has red feet). Scientists have discovered a fossil of
another grillo species (called the white grillo) that is now extinct. It has a
triangular body and shows evidence of having white feet. You hypothesize
that the blue and red grillos evolved from this ancestor species. The trees
drawn below show the relationships among these grillos:
White grillo
Blue grillo
Blue grillo
Red grillo
OR
Red grillo
White grillo
(even though these two trees look slightly different, they actually give the
same information. You may use either format when drawing your own trees)
The brown grillos and black grillos have square bodies and live in Europe.
The DNA of the brown grillo and black grillo is pretty similar. However, the
brown grillo has brown feet and the black grillo has black feet. Scientists
recently found fossils of a species called the orange grillo. This species,
which is now extinct, has a square body and shows evidence of having orange
feet. You hypothesize that the brown and black grillos evolved from this
ancestor species. These relationships can be represented in a tree that
looks like this:
Brown grillo
Orange grillo
Black grillo
Brown grillo
OR
Black grillo
Orange grillo
Just recently, scientists found a fossil of a grillo that is much older than
anything they have found before. This grillo has a round body and shows
evidence of having green feet. You hypothesize that the white grillo and the
orange grillo evolved from this original green grillo. Now, your entire tree
looks like this:
Blue grillo
White grillo
Green grillo
Red grillo
Brown grillo
Orange grillo
Black grillo
OR
Blue grillo
Red grillo
Brown grillo
White grillo
Black grillo
Orange grillo
Green grillo
Now for some vocabulary (use the Grillo Evolution handout to take notes
about key terms and to label the tree). Since the blue and red grillos
evolved from the white grillo, the white grillo is said to be the common
ancestor of the reds and blues. Likewise, the orange grillo is the common
ancestor of the browns and the blacks. We say that these common
ancestors sit at the nodes of the tree. The straight lines are called
branches. Taxa that share a common ancestor are said to be in the same
clade. This can be visualized such that if you took scissors and cut the
branch labeled A (on the handout), you would end up with the blues and reds,
as well as their common ancestor, the whites. That is one clade. The brown
grillos and black grillos are in the same clade because they share a common
ancestor, the oranges. Taxa that split from the same node (come from the
same common ancestor) are called sister taxa. So the reds and blues are
sister taxa and the browns and blacks are sister taxa.
Blue grillo
White grillo
A
Red grillo
Green grillo
Brown grillo
Orange grillo
Black grillo
Grillo Evolution Handout
Things to label on the tree:
· nodes · branches · sister taxa · common ancestors · taxa · clades
PARSIMONY
Now, what if you weren’t too sure about the sequence of the grillo evolution?
How do you know that certain features evolved before other features? The
common practice among phylogeneticists is to use parsimony.
What is parsimony?
http://evolution.berkeley.edu/evolibrary/article/0_0_0/phylogenetics_08
The parsimony principle is basic to all science and tells us to choose the
simplest scientific explanation that fits the evidence. In terms of treebuilding, that means that, all other things being equal, the best hypothesis is
the one that requires the fewest evolutionary changes.
We can use the grillo evolution to demonstrate this concept:
Our tree of grillo evolution looks like this:
Blue grillo
White grillo
A
Red grillo
Green grillo
Brown grillo
B
Orange grillo
Black grillo
This tree suggests that the triangular body shape evolved one time (on the
branch labeled A), and the square body shape evolved one time (on the
branch labeled B). We say that this tree requires 2 evolutionary changes
(the evolution of body shapes).
Someone might put together a tree of the evolution of our grillos that looks
like this:
Blue grillo
White grillo
A
Green grillo
C
D
Brown grillo
Black grillo
B
Orange grillo
E
F
Red grillo
In this case, the triangular body shape would have evolved two times (once
on branch A and again on branch F) and the square body shape would have
evolved two times (once on branch B and again on branch D). We say that
this tree requires 4 evolutionary changes.
Parsimony basically says to makes things easy. Which tree gives the
simplest explanation of grillo evolution? The first tree tells us that there
had to be only 2 evolutionary changes. The second tree tells us that there
had to be 4 evolutionary changes. 2 is less complicated than 4. So
parsimony tells us to pick the first tree.
Think of it like this: You need to take a book, a pencil, and an eraser out of
your locker and bring them to your math class. Here are two choices of how
you can accomplish this:
1) You walk to your locker and grab the book. You take the book to your
math class and put it on your desk. Then you go back to your locker and get
the pencil. Walk back to the math class and put the pencil on your desk.
Finally, go back to your locker and get the eraser and take it to the math
class.
2) Walk to your locker. Take out the book, pencil, and eraser and carry all
three of them to your math class.
Which of these choices is the simplest way to get the book, pencil, and
eraser to math class? Obviously, the second choice is the most simple.
Parsimony tells you to choose the simplest option. Don’t make things more
complicated than they have to be.
Another example of parsimony
Parsimony can help in comparing two hypotheses about vertebrate
relationships.
Hypothesis 1 requires six evolutionary changes and Hypothesis 2 requires
seven evolutionary changes, with a bony skeleton evolving independently,
twice. (evolutionary changes are marked by horizontal lines on the trees).
Although both fit the available data, the parsimony principle says that
Hypothesis 1 is better — since it does not hypothesize unnecessarily
complicated changes.
In many cases, the data are complex and may point to several different
phylogenetic hypotheses. In those cases, the parsimony principle can help us
choose between them.
http://evolution.berkeley.edu/evolibrary/article/0_0_0/phylogenetics_08
GENETICS AND MOLECULAR EVOLUTION
Summary
What does molecular data have to
do with relatedness and
evolutionary history?
This lesson demonstrates the
relationship between mutations,
nucleotide bases, amino acids,
proteins, and relationships among
organisms.
Objectives
Students will:
· make the connection between
changes in DNA sequence and the
resulting changes in the organism
and its evolution
· understand that sets of three
nucleotide bases (codons) code for
amino acids, which are the building
blocks of proteins
· understand that changes in
nucleotide bases may or may not
cause a resulting change in an
organism
Materials
· photocopies of the Genetics
and Molecular Evolution reading
· photocopies of Mutations – Get
the Point? worksheets
· photocopies of Amino Acids
sheets
· photocopies of Base Cut Outs
sheets
· envelopes containing base cutouts
Setting
Classroom
Duration
60-80 minutes
Key Terms
· nucleotide base
· amino acid
· protein
· point mutation
· codon
· phenotype
· genotype
Making Connections
This lesson will show students the
connection between molecular
changes and evolution.
Background
· Refer to the Genetics and
Molecular Evolution reading for
information.
· You can cut out the bases used
for the Mutations – Get the
Point? activity before the lesson,
or have students cut out the bases
for themselves
Procedure
Warm Up
· Have students read the Genetics
and Molecular Evolution reading
(as a class or for homework)
· Make sure that students
understand the key terms from
the reading
The Activity
1. Pass out copies of the
Mutations – Get the Point?
Worksheets, envelopes filled with
base cut outs, and copies of the
Amino Acids sheet to each student
(or pair of students)
2. Students should follow the
instructions provided on the
worksheets to complete the
activity and answer all questions.
Wrap Up
· Ask students to compare and
contrast the effects of mutations
in coding and noncoding regions of
DNA.
· Ask the students to think about
which regions are most likely to
contain mutations – coding or
noncoding regions? Why?
· Add key terms to the word wall
Assessment
· Collect the Mutations – Get the
Point? Worksheets
· Re-do the activity as a class if
students are confused…it is
important that they appreciate the
role of DNA in evolution!
Resources
· Campbell, Neil A., and Jane B.
Reece. BIOLOGY. 7th ed.
San Francisco: Pearson Education,
Inc, 2005.
· Mutations – Get the Point? is
adapted from:
Haley-Oliphant, Ann E. "Alice
Huang: Microbiologist/Molecular
Geneticist.” Women Life
Scientists: Past, Present, and
Future: Connecting Role Models to
the Classroom Curriculum. Eds.
Marsha Lakes Matyas and Ann E.
Haley Oliphant. Bethesda, MD: The
American Physiological Society,
1997. 231-239.
GENETICS AND MOLECULAR EVOLUTION
What does molecular data have to do with relatedness and evolutionary
history?
Changes in nucleotide sequence (via insertions, deletions, substitutions, etc.)
can influence the phenotype of the organism. An organism’s DNA is the
instruction manual for that organism. If you want to know why a cat is
brown, you can look to the DNA and see what sequence is coding for a
particular protein that may cause that pigmentation. An organism’s DNA
(the genotype) explains what appears physically (the phenotype). It is a
fairly simple assumption that the more similar two organisms are on the
outside (phenotypically), the more similar their DNA is (genotypically).
(there are some exceptions to this, but for now we will stick to that
assumption)
Obviously, two fairly unrelated organisms, like a human and a pine tree, will
have pretty different genetic makeups. But the more similar two organisms
are, the more similar their DNA will be. Think of you and your brother or
sister…you might have the same eye color, same funny-looking big toe, same
curly hair. You are very closely related because you came from the same
parents. But now compare yourself to the person sitting next to you in class.
That person might have straight hair while yours is curly, you skin color may
be different, and they probably don’t have that same weird toe. If you were
to compare your DNA to theirs, you can bet that they it wouldn’t be as
similar as yours is to that of your brother or sister.
BUT…even though you might not look much like that person sitting next to
you, the basic genetic code is identical in a lot of places. For example, you
both have noses. You both have red blood cells that carry oxygen to your
cells. You both have kidneys. There are many parts of your DNA that must
be a certain way, or else you wouldn’t be a human and wouldn’t be alive. If
your DNA contained some mutation that caused you not to develop lungs, for
example, you wouldn’t have survived long enough to be born. That mutation in
that part of your DNA would have caused you to be selected against…in
other words, you wouldn’t make it. These parts of DNA that must contain
certain sequences are called “conserved regions.” Any change in that
sequence would cause a vital function to be messed up and would lead to the
death of that organism.
Phylogeneticists use a variety of techniques when comparing DNA of various
organisms. Some look at regions where certain sets of bases repeat multiple
times. Others look to a specific gene which they understand well. Still
others look at portions of DNA that do not code for amino acids (and
therefore do not build proteins). These non-coding portions of DNA may be
introns, spacer regions, etc. Because these regions do not code for amino
acids (and thus do not have an effect on the functioning of the organism),
these sequences can change (mutate) and it doesn’t really matter. Mutations
that occur in these regions kind of sneak under the radar of natural
selection and thus can evolve without being detected.
No matter what the type of region that the phylogeneticist chooses to
examine, he/she is looking for differences in those sequences between one
organism and the next. The fewer the number of differences, the more
closely related the organisms are.
For example, look at the following sequences:
Organism A: A T G
G C C
T A G
G T A
A A C
Organism B: A T G
C C C
T A G
G T A
A A C
Organism C: A T G
C C C
A G G
G T A
A A C
Count the number of differences between the organisms.
You can see that there is 1 difference between organism A and organism B.
There are 2 differences between organisms B and C.
There are 3 differences between organisms A and C.
Based on these sequences, we can hypothesize that organism A is more
closely related to organism B than it is to organism C. Organism B is more
closely related to organism A than it is to organism C. B is more closely
related to C than A is to C. It might be easier to visualize it like this (where
the numbers represent the number of differences in the sequences):
1
2
A --------- B -------------------- C
MUTATIONS – GET THE POINT?
Name
Date
Background Information
· a nucleotide base is a building block for nucleic acids (eg. DNA and RNA)
· an amino acid is a building block for proteins
· a protein is a compound that makes up the structural materials and
enzymes in a cell
· a point mutation is a change in the DNA of a gene. It involves only one or a
few bases of DNA
· a codon is a set of three nucleotide bases that codes for a particular amino
acid
Procedure
1. Arrange the nucleotide bases provided in your envelope in the following
order:
TTT CTT GTC TCA AAA
(the letter A represents adenine, T is thymine, G is guanine, and C is
cytosine) (there will be extra bases in your envelope)
2. Answer the following question:
a. What amino acids are coded for by your sequence? (use the Amino
Acids sheet to answer the question)
3. Now, rearrange your bases to simulate a substitution point mutation arrange your bases in the following order:
TTT CTT GTC ACA AAA
(the 4th codon has a substitution of an A for a T)
4. Answer the following questions:
a. What amino acids are coded for by your sequence?
b. What consequence did the mutation have on the sequence of amino
acids?
5. Put your bases back in the original sequence. Now, substitute a C for the
T in the first codon – your sequence should now look like this:
TTC CTT GTC TCA AAA
6. Answer the following questions:
a. What amino acids are coded for by your sequence?
b. What consequence did the mutation have on the sequence of amino
acids?
7. Put your bases back in the original sequence. Now, rearrange your bases
to simulate an addition point mutation - add a G after the second codon
(CTT).
8. Answer the following questions:
a. Arranged in groups of three, what is the new sequence?
b. What amino acids are coded for by this sequence?
c. What effect would this have on the protein that these amino acids
are a part of?
9. Put your bases back in the original sequence. Now, rearrange your bases
to simulate a deletion point mutation – remove the third T of the first codon.
10. Answer the following questions:
a. Arranged in groups of three, what is the new sequence?
b. What amino acids are coded for by this sequence?
c. What effect might this deletion have on the protein that these
amino acids are a part of?
11. Final Questions:
a. Describe the relationships between mutations, amino acids, and
proteins.
AMINO ACIDS
(In some cases, more than one codon can code for the same amino acid.)
First Base
T
Second Base
T
C
A
G
TTT Phenylalanine
TTC
TCT Serine
TCC
TCA
TCG
TAT Tyrosine
TAC
TGT Cysteine
TGC
TAA Stop
TAG
TGA Stop
TGG Tryptophan
CAT Histidine
CAC
CGT Arginine
CGC
CGA
CGG
TTA Leucine
TTG
C
A
G
CTT Leucine
CTC
CTA
CTG
CCT Proline
CCC
CCA
CCG
ATT Isolecine
ATC
ATA
ATG Start
ACT Threonine AAT Asparagine
ACC
AAC
ACA
ACG
AAA Lysine
AAG
AGA Arginine
AGG
GTT Valine
GTC
GTA
GTG
GCT Alanine
GCC
GCA
GCG
GGT Glycine
GGC
GGA
GGG
CAA Glutamine
CAG
GAT Aspartic Acid
GAC
GAA Glutamic Acid
GAG
AGT Serine
AGC
Adapted from page 314 in Campbell, Neil A., and Jane B. Reece. BIOLOGY. 7th ed. San Francisco:
Pearson Education, Inc, 2005.
MUTATIONS – GET THE POINT? – Teacher’s Guide
Answers to questions from the worksheet:
1.
2. a. phenylalanine – leucine – valine – serine – lysine
3.
4. a. phenylalanine – leucine – valine – threonine – lysine
b. The amino acid serine has been replaced by threonine. This may have
an effect on the protein that these amino acids are a part of.
5.
6. a. phenylalanine – leucine – valine – serine – lysine
b. This had no effect on the amino acid sequence.
7.
8. a. TTT CTT GGT CTC AAA A
b. phenylalanine – leucine – glycine – leucine – lysine - …
c. This addition changed the amino acids that were coded for. This in
turn will probably change the protein that the amino acids are a part of.
9.
10. a. TTC TTG TCT CAA AA…
b. phenylalanine – leucine – serine – glutamine - …
c. The deletion changed one of the amino acids…this may end up building
a different protein than the original amino acid sequence.
11. a. Because groups of three nucleotide bases (codons) code for specific
amino acids, a mutation (substitutions, additions, deletions) may or may not
effect the amino acids that are coded for. If the amino acids are changed,
that can effect proteins (because amino acids are the building blocks of
proteins).
BASE CUT OUTS
· Make 1 copy of this sheet/student (or per pair of students if they will be working in pairs)
· Cut out each of the letters below.
· Place a full set of letters in an envelope
T
T
T
T
T
T
T
T
T
T
A
A
A
A
A
A
A
A
A
A
G
G
G
G
G
G
G
G
G
G
C
C
C
C
C
C
C
C
C
C
BIOGEOGRAPHY
Summary
How does biogeography affect the
distributions of species?
This lesson introduces students to
biogeography.
Objectives
Students will:
· know what the study of
biogeography is
· understand how plate tectonics
and glaciation affect the
distribution of organisms
Materials
· photocopies of the Biogeography
reading
· overheads or photocopies of
Watching the Continents Drift
and Pine Oak Spruce Distribution
Setting
Classroom
Duration
Dependent on which activity you
choose
Key Terms
· biogeography
· plate tectonics
Making Connections
Students are probably already
aware of the concepts of
continental drift and plate
tectonics, but after this lesson
they will appreciate the impact
that these processes have on the
distribution of species.
Background
Please refer to the Biogeography
reading.
Procedure
Warm Up
· In class or as a homework
assignment, have students read
the Biogeography reading. Discuss
the reading and review key terms.
· Show students the movement of
the continents with the Watching
the Continents Drift sheets.
· Show the students the Pine Oak
Spruce Distribution page and have
them discuss how the movement of
the ice sheet affected the plants’
distributions.
Possible Activities
I. Continental Drift Flip Books
(homework activity)
Students make flip books that
show the movement of the
continents.
1. Students staple several small
pieces of paper together (3”X3”).
2. Students draw the slow drift of
the continents – each page holds a
picture slightly different from the
one before and after it, so that
when you flip the pages very
quickly, you can see the continents
moving
II. Lovers divided
(60-80 minutes)
1. Students research an organism
that has a divided distribution as a
result of continental movement.
2. In small groups, students act
out an exaggerated situation in
which these organisms must part
with their loved ones as the
continents drift apart.
Wrap Up
· Review key terms and add them
to the word wall
Assessment
· Have the students write a short
essay explaining the effect that
plate tectonics and glaciation can
have on the distribution of
organisms.
Resources
Understanding Evolution:
http://evolution.berkeley.edu/evoli
brary/article/_0/history_16
BIOGEOGRAPHY
What exactly is biogeography, and why is it useful in phylogenetics?
Wallace and Wegener
(http://evolution.berkeley.edu/evolibrary/article/_0/history_16)
In one of his most important applications, Alfred Russell Wallace helped
found the modern science of biogeography — the study of how species are
scattered across the planet, and how they got that way.
Patterns of species' ranges
”Wallace had already accepted evolution when he began his travels in 1848
through the Amazon and Southeast Asia. On his journeys, he sought to
demonstrate that evolution did indeed take place, by showing how geography
affected the ranges of species. He studied hundreds of thousands of
animals and plants, carefully noting exactly where he had found them. The
patterns he found were compelling evidence for evolution. He was struck, for
example, by how rivers and mountain ranges marked the boundaries of many
species' ranges. The conventional explanation that species had been created
with adaptations to their particular climate made no sense since he could
find similar climatic regions with very different animals in them.
Wallace came to much the same conclusion that Darwin published in the
Origin of Species: biogeography was simply a record of inheritance. As
species colonized new habitats and their old ranges were divided by mountain
ranges or other barriers, they took on the distributions they have today.
This map from Wallace's 1876 book shows his Oriental biogeographic region, broken into four
subregions (outlined in red). "Wallace's Line" is indicated by the arrow. Click for an
enlargement.
Wallace pushed the study of biogeography to grander scales than Darwin. As
he traveled through Indonesia, for example, he was struck by the sharp
distinction between the northwestern part of the archipelago and the
southeastern, despite their similar climate and terrain. Sumatra and Java
were ecologically more like the Asian mainland, while New Guinea was more
like Australia. He traced a remarkably clear boundary that snaked among the
islands, which later became known as "Wallace's Line." He later recognized
six great biogeographical regions on Earth, and Wallace's Line divided the
Oriental and the Australian regions.
Plate tectonics
The biogeographic regions of the world that Wallace
recognized roughly coincide with the continents themselves.
But in the twentieth century, scientists have recognized
that biogeography has been far more dynamic over the
course of life's history. In 1915 the German geologist
Alfred Wegener (left) was struck by the fact that identical
fossil plants and animals had been discovered on opposite sides of the
Atlantic. Since the ocean was too far for them to have traversed on their
own, Wegener proposed that the continents had once been connected. Only
in the 1960s, as scientists carefully mapped the ocean floor, were they able
to demonstrate the mechanism that made continental drift possible — plate
tectonics.
Wegener found that the distributions of fossils of several organisms supported his theory that the continents were once joined
together.
Biogeographers now recognize that as continents collide, their species can
mingle, and when the continents separate, they take their new species with
them. Africa, South America, Australia, and New Zealand, for example, were
all once joined into a supercontinent called Gondwanaland. The continents
split off one by one, first Africa, then New Zealand, and then finally
Australia and South America. The evolutionary tree of some groups of
species — such as tiny insects known as midges — show the same pattern.
South American and Australian midges, for example, are more closely
related to one another than they are to New Zealand species, and the
midges of all three land masses are more closely related to one another than
they are to African species. In other words, an insect that may live only a
few weeks can tell biogeographers about the wanderings of continents tens
of millions of years ago.”
To Sum it Up…
The field of biogeography involves:
· the study of the distribution of organisms over the earth
· the history and biology that contributed to the distribution
· hypotheses and theories based on geological evidence and the fossil
record
Plate tectonics:
· explains movement of continents and some biogeographic patterns.
· explains that plates of earth’s crust overlap
Something else to think about:
Glaciation also has an affect on the biogeography of organisms. The last
glacial period lasted from around 100,000 ybp (years before present) to
about 12,000 ybp. The ice sheet present during that time, called the
Laurentian Ice Sheet, was over one mile thick and covered a large portion of
North America. The formation and melting of ice sheets have affected the
distributions of many species. For example, at the height of the glacial
period, Jack pine (Pinus banksiana) grew as far south as Georgia. Today Jack
pine does not grow south of New England.
WATCHING THE CONTINENTS DRIFT
There once were two frogs of Gondwana,
who vowed ne'er part til Nirvana.
But each met its fate
on a separate plate;
He lies in Brazil,
She in Ghana.
The following pages demonstrate the way in which the continents came to lie as they do today.
(the distribution of the species is shown in green)
SECTION 2
Gymnosperm Case
Study
GETTING TO KNOW THE GYMNOSPERMS
Summary
What are gymnosperms and
conifers? What are some features
that are useful for identification?
This lesson introduces students to
the group of plants known as the
gymnosperms. Background reading
and a hands-on activity provide the
students with a basic knowledge of
the group and some features used
in identification.
Objectives
Students will:
· know the major features of
gymnosperms and conifers
· draw and describe the cones,
twigs, seeds, and uses of various
gymnosperms
· be able to classify a plant by
family and genus
Materials
· photocopies of the Getting to
Know the Gymnosperms reading
· photocopies of the Getting to
Know the Gymnosperms worksheet
· plant material: cones, twigs,
seeds (and whatever else is
available) of various gymnosperms
(you will need to collect these in
the outdoors unless other sources
of material are available)
· Station Information Sheets
(one or two copies/station)
· dissecting microscopes
· rulers
· hand lenses or magnifying glasses
· dissecting kits
· examples of gymnosperm
products (refer to the Forest
Products page for details)
Setting
Classroom
Duration
60 – 80 minutes
Key Terms
· gymnosperm
· conifer
· cone
Making Connections
Many students have probably seen
gymnosperms before, but they may
only know the common names or
may have misconceptions about the
plants. This lesson gives every
student a chance to observe and
inspect gymnosperms closely. The
knowledge that they gain from this
lesson will be useful in the rest of
the unit and will be useful when
they see these plants in their
everyday lives.
Background
Please refer to the Getting to
Know the Gymnosperms.
(The students may be wary of
learning the scientific names of
these plants. However, this is a
very useful skill and will benefit
them in the long run, so please
make the effort to teach the
students the correct names and
spellings.)
a Station Information Sheet,
rulers, dissecting microscopes,
hand lenses, and dissection kits.
Procedure
3. Make an answer key for
yourself by completing a Getting
to Know the Gymnosperms
Worksheet for each different
gymnosperm and recording the
name of the gymnosperm and
corresponding sample number that
you have assigned to it. (this
answer sheet will be used later in
the activity).
Warm Up
1. In class or as a homework
assignment the night before, have
students read Getting to Know
the Gymnosperms
2. Hold a brief discussion with
students to review the key terms
from the reading and to gain a
sense of what they already know
about gymnosperms and conifers.
The Activity
1. Set up stations around the
classroom. Ideally, there will be a
Cone Station, Twig Station, Seed
Station, and Product Station. If
you are not able to find seeds, for
example, there are resources
available with pictures of seeds
that can be substituted for the
actual material.
Each station should include plant
material (or pictures) from about 5
different genera of gymnosperms
that can be found in the local area,
2. Label all of the plant samples
with numbers instead of names.
For example, label all of the
samples (the cone, the twig, the
product, the seeds) collected from
a pine tree #1, all samples from a
hemlock #2, etc.
4. Assign students a Sample
Number (1, 2, 3, 4, or 5).
5. After being assigned a Sample
Number, the students will move
around the stations that have been
set up. If a student has been
assigned Sample Number 1, he/she
must examine the cone that is
labeled #1, the twig that is labeled
#1, the seeds that are labeled #1,
and the product that is labeled #1.
The students will complete the
Getting to Know the
Gymnosperms Worksheet as they
circulate among the stations.
6. After the students have visited
each station and have made their
observations, they need to find out
the names of their samples. You
should read (or post) your
observations from the answer
sheet that you completed earlier.
Students need to compare their
observations to the answer sheet
in order to figure out what plant
they studied. For example, if you
say that a pine tree (Pinus) has
needles in bundles, the student
whose own observations match
that description would know that
he/she studied a pine and will
record that on the worksheet.
(Provide students with the common
name and scientific name of each
genus)
If a student has not made good
observations during the activity,
then they will probably not be able
to figure out what plant they have.
In this case, allow more time for
observations and assist the
students in making quality
observations.
Modifications
Instead of giving the students the
Getting to Know the
Gymnosperms worksheet, have
them make their observations
without being asked specific
questions. See what sorts of
things they would look for if not
prompted by the worksheet
questions.
Wrap Up
· End the activity with a brief
discussion about the gymnosperms
that the class studied during the
activity. Did anyone know the
sample right away? Had anyone
seen the cones or twigs or seeds
from the samples before? Does
anyone know where to find more
samples of gymnosperms?
· Add the key terms to the word
wall.
· Begin to classify gymnosperms
into families and genera by making
a gymnosperm bulletin board (see
Gymnosperm Bulletin Board sheet
for instructions).
· Start Gymnosperm Journals (see
Gymnosperm Journal – Teacher’s
Guide for more information)
Assessment
The worksheets may be collected
and graded.
Extensions
Encourage students to collect
material from gymnosperms and
bring that material into class for
use in later lessons and study.
Resources
· University of Hawaii,
Coniferophyta - Coniferales
http://www.botany.hawaii.edu/facu
lty/webb/Bot201/Conifers/conifer
_lecture.htm
· Irving Forest Discovery Network
www.ifdn.com
· Maine Forest Service
http://www.maine.gov/doc/mfs/pu
bs/ftm/ftm_sw.htm
· FAO Corporate Document
Depository, Non-wood forest
products from conifers, Chapter
10
http://www.fao.org/docrep/X0453
E/X0453e14.htm
GETTING TO KNOW THE GYMNOSPERMS
Translated literally, the word gymnosperm means “naked” (gymno) “seed”
(sperm). Gymnosperms do not produce true flowers or fruit, and therefore
the seeds of gymnosperms are not enclosed in flowers or fruit. The seeds
of most gymnosperms develop on the surface of the scales of female cones.
The gymnosperms include the Cycads, the Ginkgo family, the conifers, and
the Gnetales. Together, they represent about 15 families, 75-80 genera,
and about 820 species. Gymnosperms are thought to be more “primitive”
than the angiosperms (flowering plants). The cells that make up the xylem
(the water-transporting part of a plant) of gymnosperms (except Gnetales)
are different from those of angiosperms. Gymnosperms reproduce fairly
slowly. More than a year may pass between pollination and fertilization, and
it can take seeds up to 3 years to mature! Also, most gymnosperms are
wind-pollinated. Gymnosperms are all woody plants (trees, shrubs, or vines)
and grow throughout most of the world, from 72º north latitude to 55º
south latitude. They are dominant in many colder and arctic regions.
Gymnosperms are some of the tallest, most massive, and longest-lived plants
in the world. Humans use several species as ornamentals and sources of
high-quality wood.
You probably already know a little bit about conifers. The conifers are the
largest and most economically important group of gymnosperms. The
conifers include such plants as the pines, spruces, yews, hemlocks, firs,
junipers, redwoods, and many others. The plants in this group are called
conifers because most of them bear their seeds in specialized structures
called cones. Cones protect ovules and seeds and aid pollination and
dispersal. (Judd et al, 2002)
Some people often get confused about the relationship between conifers and
gymnosperms. Conifers are a group of gymnosperms. Are all conifers
gymnosperms? YES. Are all gymnosperms conifers? NO.
Here are a few photos of some of the lesser-known gymnosperms:
Ginkgo
http://www.ucmp.berkeley.edu/seedplants/ginkgoales/notchedleaves.jpg
Cycads
http://waynesword.palomar.edu/images/encnat1b.jpg
Gnetales
http://images.google.com/imgres?imgurl=http://www.conifers.org/we/welwit
schia5.jpg&imgrefurl=http://www.conifers.org/topics/sowhat.htm&h=486&w
=716&sz=31&hl=en&start=9&tbnid=0Nsap7LDlG3v0M:&tbnh=95&tbnw=140&p
rev=/images%3Fq%3Dgnetales%26svnum%3D10%26hl%3Den
GYMNOSPERM PROUNCIATION GUIDE
Some of the Latin names of the gymnosperms can be a little tricky to
pronounce. Even scientists differ in the ways that they pronounce the
names. Here are some suggestions of pronunciations for names you will be
using a lot. (The syllable that should be stressed is bold and underlined)
Abies
A-bees
Cupressaceae
coo-press-A-C-E
Juniperus
joo-nip-er-us
Larix
lare-ix
Picea
pie-C-ah
Pinaceae
pie-nay-C-E
Pinus
pie-nus
Pseudotsgua
soo-dough-soo-ga
Taxaceae
tax-A-C-E
Taxus
tax-us
Thuja
thoo-ja
Tsuga
soo-ga
GETTING TO KNOW THE GYMNOSPERMS
Name:
Date:
Sample Number:
Instructions: There are various stations set up around the room (cone
station, twig station, seed station, product station). Your teacher will give
you a sample number. At each station, you need to find the sample that has
your number on it and examine only that sample. For example, if you are
given sample #2, then when you go to the cone station you need to examine
the cone that is labeled #2. When you go to the twig station, you will find
the twig that is labeled #2. And so on. Complete this worksheet based on
your observations of your samples. Please refer to the information pages
available at each station to help guide your observations.
Twig Station
1. Draw a picture of your twig as it appears with the naked eye.
2. Draw a picture of your twig as it appears under the microscope, hand
lens, or magnifying glass. (be sure to record the magnification that you
used)
3. Describe the leaves on your twig:
· are they needle-like, scale-like, or something completely different?
· what color are they?
· how long are they?
· do the leaves attach directly to the twig?
· are the leaves clustered together? (and if so, how many/bundle?)
· any other noteworthy observations
Cone Station
1. Draw a picture of your cone as it appears with the naked eye.
2. Draw a picture of your cone as it appears under the microscope, hand
lens, or magnifying glass. (be sure to record the magnification that you used)
3. Describe your cone:
· how big is it?
· what color is it?
· are the scales overlapping?
· does your cone have any prickles on it or anything spiney or sharp?
· any other noteworthy observations
Seed Station
1. Draw a picture of one of your seeds as it appears with the naked eye.
2. Draw a picture of one of your seeds as it appears under the microscope,
hand lens, or magnifying glass. (be sure to record the magnification that you
used)
3. Describe the seeds:
· how many seeds are there on each cone scale?
· where are the wings on the seed? how many wings/seed?
· how big are the seeds?
· any other noteworthy observations
Product Station
1. What is one use or product of your sample?
2. Have you ever used that product? Explain.
Identification
Based on the information that your teacher will provide at the end of the
activity, determine the name of the plant you have been studying.
Common name:
Scientific name:
CONE STATION
Conifers have male and female cones. The woody cones that you are
probably familiar with are the female cones. They are larger than the male
cones and more easily noticed. The male cones are usually herbaceous. The
male cones produce large amounts of pollen. The pollen is carried by the
wind to the female cones. After the female cones are pollinated, they begin
to harden and close up. They can remain closed for several years while the
seeds ripen inside. On a warm day, when the cone is ready, it will open to
allow its winged seeds to be carried away by the wind.
male cones
female cones
Here are some basic features to look for on a female cone:
(female cone)
http://www.botany.hawaii.edu/faculty/webb/Bot201/Conifers/conifer_lectu
re.htm
SEED STATION
Conifer seeds develop on the female cone. The cones can take from 4
months to 3 years to mature. When the cone is finally mature, the scales
usually spread open and the seeds are allowed to fall out. They are
dispersed by the wind and have wings which aid in this type of dispersal. In
some conifers, the scales fall away from the cone axis while it is still
attached to the branch.
Conifer seeds can persist in the soil for decades. They can withstand
freezing and fires. Cones of lodgepole pine will not open unless they are
exposed to the heat of a forest fire.
PRODUCT STATION
There are many, many, many uses of gymnosperms around the world.
Virtually every part of the tree (foliage, bark, roots, resin, seeds, cones) can
be used for something. Whole trees are often used in landscaping and for
ornamental purposes. Spruces and firs are popular Christmas trees. If you
have even eaten pine nuts (one of the ingredients in pesto, sometimes
available as a topping on pizza, etc.), then you have eaten the seeds of the
pinyon pine. You have probably seen conifer bark in mulches. The fruits and
foliage of Ginkgo biloba are used in medicines for improving memory, eye
problems, and various other conditions. Recent research has led to the
discovery of the anti-cancer agent, taxol, from the bark of Taxus brevifolia.
Needless to say, there are countless products that come from gymnosperms.
FOREST PRODUCTS – Teacher’s Guide
This page is a list of common products of several genera of gymnosperms.
The Product Station should include physical examples of some of these
products (if possible) or lists of the products. (information was obtained
from International Paper’s Trees of the Northeast Product Guide)
FIR (Abies)
· Christmas trees
· wreaths
· structural lumber
· pulp/paper
· fuel chips
HEMLOCK (Tsuga)
· framing lumber
· roof boards
· timbers
· docks and pilings
· landscape ties
· pulp/paper
· fuel chips
SPRUCE (Picea)
· lumber
· sounding boards for musical
instruments
· magazine paper
· pulp/paper
· fuel chips
PINE (Pinus)
· lumber
· cabinet making
· furniture
· boat planking
· house trim
· landscape ties
· pulp/paper
· fuel chips
TAMARAK – LARCH (Larix)
· planking
· timbers
landscape ties
· vats
· ship’s knees
· plywood
· pulp/paper
· fuel chips
NORTHERN WHITE CEDAR –
ARBOR VITAE (Thuja)
· railroad ties
· shingles
· poles
· posts
· rustic fencing
· lumber for boxes, crates, siding,
and boats
EASTERN RED CEDAR –
JUNIPER (Juniperus)
· pencils
· fence posts
· pails
· cabinet making
TWIG STATION
The leaves of conifers often do not look like typical leaves. The leaves of
many are needle-like, and the leaves of several others are scale-like.
The leaves of most conifers are present year-round. This means that they
are able to photosynthesize year-round, if necessary. The needles of
conifers are coated with a wax which prevents water loss. The shape of the
needles cuts down on wind resistance. In addition, most leaves are highly
resinous (think of how sticky your fingers get while handling some of these
samples), which helps them to withstand freezing.
Although at first glance you might think that all needles are needles, closer
inspection reveals many differences among conifer leaves. Pay attention to
how the needles are attached to the twig. Are they clustered together in
bundles? Are they attached on a little woody peg? The shape of the
needles can also be informative. Are the needles flat? Can you spin them
between your fingers? Even the flexibility or stiffness of the needles can
be helpful in identification. Do the needles snap as soon as you try to bend
them? Is the end of the needle sharp?
sharp-tipped needle
needles in bundles:
GYMNOSPERM BULLETIN BOARD - Teacher’s Guide
It will be very helpful to make a Gymnosperm Bulletin board in the classroom
that the students can elaborate on and refer to for the remainder of the
unit. The board should be divided up by family and genus. The three most
common families that you will encounter (most likely) are the Pinaceae (the
Pine Family), the Cupressaceae (the Cypress Family), and the Taxaceae (the
Yew Family). Within these families, there are several common genera. The
bulletin board should include: the common and scientific names of the major
families and genera, main distinguishing characteristics of each group, and
pictures of or material from each group.
Information on several genera is provided on the following pages. (These
pages may provide more or less information than you want to include on your
board.) The bulletin board can be something that you make all at once, or
the students may want to build it gradually as they encounter various genera.
GINKGOACEAE (Ginkgo or Maidenhair Tree Family)
·
·
·
·
·
Grow as trees
Extinct in wild?
Dioecious (separate male and female plants)
Seed smells like rancid butter
Distinctive leaves, unlobed on reproductive short shoots,
lobed on vegetative branches
·
·
·
·
Wood contains vessels (part of the xylem)
Branches usually photosynthetic
Leaves scale-like, early deciduous
3 families, 3 genera
Ephedraceae (Mormon tea or Joint fir family)
· Wood contains vessels
· Branches usually photosynthetic
· Leaves scale-like, early deciduous
GNETALES
Welwitschia mirabilis
· Dioecious (separate male and female plants)
· Only 2 leaves, which shred from the tip over the years
· Grows only in Namib and Mossamedes deserts, s.w. Africa (2.5
cm rain/year)
PINACEAE (Pine Family)
· Leaves needle-like, spirally arranged
· Cone scales overlapping, flat, distinct from bract
· Seeds with terminal wing, 2 seeds/cone scale
Pinus (Pine)
· Trees of various acid and usually sandy
soils, coasts, lower elevations
· Bark smooth on young trees but can be
deeply furrowed on large trees
· Leaves needle-like, flexible or stiff,
with sharp tips, in fascicles (bundles) of
2-5
· Cone hangs down, can be 4-9” long
depending on the species
· Cone scales stiff or flexible depending
on species
· Wood of E. white pine (P. strobus) and
red pine (P. resinosa) used for
dimensional lumber; seeds eaten by
squirrels, other mammals, birds
Picea (Spruce)
· Trees of moist, acid soils, coasts, bogs,
high elevations
· Leaves needle-like, stiff, with sharp
tips, with stomatal bands
· Needles 3-4-sided, on woody pegs
(sterigmata)
· Cone scales thin
· Bark scaly, can be red-brown to silvery
gray · Cone hangs down, can be 1-4” long
depending on the species· Wood valued
for
pulp and dimensional lumber. Many
animals eat the seeds.
Larix (Larch)
· Deciduous conifer of moist, acid soils
and bogs
· Leaves needle-like, soft, with blunt
tips, no stomatal bands visible; fall off in
late autumn
· Needles borne on short shoots, appear
whorled because internodes very short
· Seed cones upright on branch
· Cone scales thin
· Cones mature in 1 year
· Bark scaly, brownish-gray
· Cone erect, 1/2-3/4” long with about
20 brownish scales
· Wood used for poles, cross-ties,
pulpwood, ship knees. Porcupines eat the
bark and leaves.
Abies (Fir)
· Needles flat, flexible, with blunt tips,
form suction-cup-like attachment to twig
· double whitish stripes on underside of
needles are stomatal bands
· Cones sit upright on branches, about 24” long
· Cone scales fall from cone axis
· Buds covered in resin
· Fast-growing, short-lived tree of
moist, acid soils
· Popular Christmas tree, branch tips
used for making wreaths.
· Long fibers in wood have been valuable
renewable resource for making paper;
also milled for dimensional lumber
Tsuga (Hemlock)
· Shade-tolerant trees of cool, moist
slopes (lower to mid elevation), and near
the coast, often in mixed forests and
rarely in pure stands; long-lived (to ca.
600 yrs, but heart rots so it is difficult
to age with corer)
· Bark deeply furrowed on large trees;
chips have purple on underside (good
field character, works even on old
stumps)
· Leaves ca. ½ in long, dark yellowishgreen, needle-like and flattened, more or
less opposite, in single plane so branches
appear flat; tip blunt; two stomatal
bands on underside
· Cone 5/8-3/4 in long with about 12-16
flexible scales
· Wood formerly used for tanning
leather; more recently for dimensional
lumber, newspaper pulp.
· Currently in crisis because of hemlock
woolly adelgid, an insect
Pseudotsuga (Douglas-fir)
· Trees of temperate rain forests from
Pacific coast and east to Rockies; can
reach close to 300’ in height and live to
over 1000 yrs
· Bark smooth on young trees but can be
deeply furrowed on large trees
· Leaves needle-like, single, flexible and
rounded at tip, standing out from twig
· Cone hangs down (pendant), 2-4” long
· Cone scales stiff, brown, with 3pronged bracts
· Cones mature in 1 year
· 2 whitish stomatal bands on underside
of leaf
· The most important timber tree of
western forests.
· Wood used for dimensional lumber
· Old growth forests can be habitat for
marbled murrelet and northern spotted
owl
CUPRESSACEAE (Cypress Family)
· Leaves scale-like or needle-like, spiral, opposite or whorled
· Cone scales valvate (the edges meet but do not overlap) or overlapping (if so, then leaves are scale-like
and opposite),
· Cone scales flat or peltate (the stalk is attached to the flat surface, like an umbrella), fused to bract
· Seeds with 2-3 lateral wings
· 1-20 seeds/cone scale
Juniperus (Juniper)
· Shrubby low plants of acid soil, sunny openings
· Leaves evergreen, awl-shaped, stiff, sharp-pointed, whitish
beneath
· Cones FLESHY, glaucous (waxy coating), blue – look like
“berries”
· Dioecious (separate male and female plants)
· Leaves in some species dimorphic: linear and whorled on
juvenile growth; scale-like, opposite and overlapping on
reproductive branches
· Bark peels in vertical strips
· Wood and foliage aromatic
· Wood of Juniperus virginiana, and Eastern red cedar, used for
making pencils
Thuja (Arbor-vitae)
· Trees of wet areas, may form monotypic stands
· Leaves evergreen, tiny, opposite, overlapping and covering twig
· Cone erect, 1/3-1/2” long, with 8-12 thin brown flat scales
· Bark peels in vertical strips
· Wood and foliage aromatic
· Ecologists notice that these indicate higher pH soils than
typical in Maine
· Often planted as hedge or landscape subject ·
· Popular hedge plant, also used for posts, poles, shingles
· Deer eat the foliage in winter
·
·
·
·
Taxus (Yew Family)
TAXACEAE (Yew Family)
Small trees or shrubs
Dioecious (separate male and female plants)
Leaves alternate, often appearing 2-ranked, initial source of taxol
Seed poisonous, with hard outer coat, usually with fleshy, brightly colored aril
· Scraggly or upright shrub may be 5’ high, usually grows in moist, rich soils along streams and rivers
· Dioecious (pollen produced on one plant, poisonous seeds on another)
· Bark reddish, peels in shreds
· Leaves dark green, needle-like, single, flexible, without stomatal bands
· Seed is covered by a juicy red aril, looks like a “berry”; is supposedly edible but hard-coated seeds and foliage highly poisonous to
people
· Deer eat the foliage in winter
· Asian cultivars used in landscape plantings, tolerate shade
· Contains taxol, a powerful medicine used to treat cancer (now synthesized)
·
·
·
·
·
Cycadaceae (Cycad family)
Cycas
CYCADS
Often palm-like
Dioecious (separate male and female plants)
Can contain poisonous compounds
Evolved 280 MYA, Carboniferous, early Permian
Now, mostly southern hemisphere relicts or evolutionary dead-ends
Zamiaceae (Coontie family)
9-10 genera
Box turtle is principal disperser of Zamia floridana seeds
GYMNOSPERM JOURNAL – Teacher’s Guide
Students should keep a gymnosperm journal during this unit. This will
encourage students to look for and think about gymnosperms when they are
out of the classroom. It will help them to remember key terms and features
discussed in class and will extend the scope of their learning. The format of
the journal is up to you. Some suggestions are listed below:
· The journal should be graded, but grading should be based on effort and
content rather than grammar, spelling, etc.
· The journal should be collected in the middle and at the end of the unit to
discourage students from waiting until the last minute to start their entries.
· The journal should consist of anything gymnosperm-related (picking out
Christmas trees, driving down the road and seeing spruce trees and
wondering how they get so big, eating in a restaurant with walls made of
knotty pine, reflecting on the lessons from class, etc.)
· Occasionally you may want to provide a topic that students must address in
their journals. Examples: Describe at least one way that gymnosperms are
present in your everyday life. What did you think about today’s lesson on
Getting to Know the Gymnosperms? What did you learn? What type of
gymnosperm do you think is most prevalent in our area?
. Entries should be made at least twice a week.
· Entries can include text, pictures, plant material, etc. (Let the students be
creative)
MAKING A DICHOTOMOUS KEY
Summary
What is a dichotomous key and how
can we make one for gymnosperms?
In this lesson, students will make
their own dichotomous keys that
they will use to identify
gymnosperms in the field.
Objectives
Students will:
· understand how to use a
dichotomous key
· make their own dichotomous keys
to gymnosperms
Materials
· photocopies of the Dichotomous
Key handout
· plant material of various local
gymnosperms
· rulers
· dissecting microscopes
· hand lenses or magnifying glasses
Setting
Classroom
Duration
45 - 60 minutes
Key Terms
· dichotomous key
· couplet
Making Connections
Dichotomous keys are used in many
fields. Being able to use a
dichotomous key is a skill that
students will use again and again.
Background
Please refer to the Dichotomous
Key handout.
Procedure
Warm Up
Briefly review features of
gymnosperms that are useful for
identification (explored in Getting
to Know the Gymnosperms
activity), such as cone size, needle
shape, needle-arrangement, etc.
The Activity
1. Pass out copies of the
Dichotomous Key handout
2. Discuss what a dichotomous key
is and what it can be used for.
3. With the students’ input,
prepare a dichotomous key to the
5 beverages listed on the
Dichotomous Key handout.
4. Provide the students with plant
material from which they will make
their own dichotomous keys.
5. Make sure that the students’
keys make sense and will be useful
to in the field.
Wrap Up
· Have students share their
dichotomous keys with one another
and make appropriate changes to
improve their keys.
· Add the key terms to the word
wall.
Assessment
The true test of the students’
knowledge of dichotomous keys will
come when they have to use their
keys to identify plants during the
field lessons.
Extensions
Encourage students to find
published dichotomous keys to
gymnosperms and compare them to
their own keys.
Resources
How to Construct and Use a
Dichotomous Key
http://www.zoo.utoronto.ca/able/v
olumes/vol-12/7-timme/7timme.htm
DICHOTOMOUS KEYS
A dichotomous key is a biological tool for identifying unknown organisms to
some taxonomic level (e.g., species, genus, family, etc.). It is constructed of
a series of couplets, each consisting of two statements describing
characteristics of a particular organism or group of organisms. A choice
between the two statements is made that best fits the organism in question.
The statements typically begin with broad characteristics and become
narrower as more choices are required.
(http://www.zoo.utoronto.ca/able/volumes/vol-12/7-timme/7-timme.htm)
Here is an example of a dichotomous key to some conifers with needle-like
leaves:
1. Needles are in bundles ……………………………………………………………………………………….. 2
1. Needles are borne singly ……………………………………………………………......................... 4
2. There are 5 needles/bundle ………………………………………………… White pine
(Pinus strobus)
2. There are 3 needles/bundle ………………………………………………….................. 3
3. Needles are 6” to 9” and rather stiff ……............. Loblolly pine
(Pinus taeda)
3. Needles are very long (8” to 18”) with a ragged sheath…Longleaf pine (Pinus palustris)
4. Needles are stiff, sharp, 4-sided (and can be twirled between the
thumb and forefinger) …………………………………………………………………………………. 5
4. Needles are flat and flexible ……………………………………………………………….. 6
and the key would continue…
Each pair of statements in the key is called a couplet. In this example, if
you were looking at a plant that had needles held together in bundles, you
would proceed to step #2. At #2, you have to examine how many
needles/bundle your plant has. If it has 5 needles/bundle, then you know
that you have a white pine (Pinus strobus). If your plant has 3
needles/bundle, then you are sent to step #3 and have to examine another
characteristic.
If you had a plant that had needles borne singly (not in bundles), then
immediately you are sent down to step #4 and you follow the couplets from
there.
Dichotomous keys can be much larger than this example, but the technique is
the same.
As a class, practice making a dichotomous key to Coca Cola, Sprite,
Coffee, Orange Soda, and Gatorade.
GYMNOSPERM DICHOTOMOUS KEY
Now that you understand what a dichotomous key is and how to build one,
you need to make a dichotomous key to gymnosperms. Your teacher will
provide you with various samples from local gymnosperms. You need to
prepare a dichotomous key to these plants. You will use this key to identify
gymnosperms during the field class, so make sure that you understand your
key and it will be easy to use in the field. Use features that will be easy to
see in the field, such as leaf shape (needle-like? scale-like?), size of leaves
(8”-18”? 2”-5”?), cone shape and size, needles flat or rounded, etc.
Dichotomous Key - Teacher’s Guide
After the students have been introduced to the idea of a dichotomous key,
help them make a key to Gatorade, Coca Cola, Sprite, Orange Soda, and
Coffee.
The key might look something like this:
1. Carbonated ……………………………………………………………………………………………………………. 2
1. Not carbonated ……………………………………………………………………………………………………. 4
2. Clear liquid, lemon-lime flavor ……………………………………………………. Sprite
2. Not clear liquid, not lemon-lime flavor ……………….………………………………. 3
3. Orange liquid ……………………………………………………………. Orange Soda
3. Brown liquid ……………………………………………………………………. Coca Cola
4. Usually served hot ………………………………………………………………………… Coffee
4. Usually served cold …………………………………………………………………... Gatorade
(They key that your class develops might be different from this one, but as
long as the basic dichotomous key format is the same, then that is fine).
GYMNOSPERM OLYMPICS
Summary
How will we remember all of
this???
This lesson presents several fun
activities designed to help
students remember names and
characteristics of various
gymnosperms. There is no formal
assessment associated with these
activities.
Objectives:
Students will:
· be able to classify various
gymnosperms by family and genus
· have fun while classifying
gymnosperms
Activity 1 – Memory
This activity is designed to help
students learn the common and
scientific names of various genera.
The game is played like the classic
Memory Match game.
Set Up and Materials
· Make a game board for each
family that you want your students
to know. The total number of
squares on the board = 2 x number
of genera. The game board can be
made out of cardboard or poster
board, and the squares can be
marked out with tape.
· Make 2 cards for each genus: one
card should have the genus’s Latin
name on it and the other should
have the common name. These
cards can be as fancy as you want
to make them. To keep it simple
you can just cut up index cards. If
the game will be played multiple
times, laminating the cards is a
good idea.
Playing the Game
Place all of the cards face down on
the board. The first student turns
over 2 cards. If those 2 cards
match (the scientific name
corresponds to the common name),
then that student removes those
cards from the board and keeps
them. If the two cards do not
match, then the student returns
them, face down, to the board, and
it is the next student’s turn. The
next student follows the same
procedure. The students must try
to remember where certain cards
lie on the board in order to get
matches.
This game not only challenges the
students’ memory of the board,
but also their memory of the
common and scientific names of
genera.
Activity 2 – Classification Relay
Race
This activity tests students’
knowledge of families and genera.
You can modify it in several ways.
Some suggestions for modification
are given at the end of the
description.
This game should be played on a
grassy field or in a gym because
the students will need room to run
around.
Set Up and Materials
· Designate a starting line on the
field. Place a bucket (or trash can
or basket, etc.) on the starting
line. This bucket can include
cones, leaves, pictures, index cards
with lists of characteristics, etc.
of various genera that you want
the students to know.
· Place more buckets about 20
feet away from the starting line.
Label these with the names of
genera that you want your
students to know. For example,
label one Abies (Fir), one Picea
(Spruce), one Tsuga (Hemlock),
etc.
Playing the Game
Divide the class into teams. Each
team should line up, single file, on
the starting line. When you say
“GO”, the first student in each line
must grab an item from the
starting line bucket. They then
must run to the genus buckets and
place that item in the correct
genus bucket. For example, if a
student grabs a pine cone, he/she
must run to the Pinus (Pine) bucket
and deposit the cone in that
bucket.
Continue playing until everyone has
had a turn. You should inspect the
buckets to ensure that items were
classified correctly. The winning
team is the one that correctly
classified the most items. If it is
a tie, then the win goes to the
team that finished first.
Modifications
· Instead of genus buckets, you
could use family buckets.
Students must classify items by
family. You also could put only
name cards in the starting bucket.
The students must place the genus
name in the correct family bucket.
· To add a little bit more
excitement, you could turn this
into a “dizzy bat race.” Place a
wiffle ball bat at the front of each
team. Before running to the
buckets, each student must hold
the bat vertically (with one end
touching the ground), place his/her
forehead on the end of the bat,
and spin around 5 times (or
increase it, if you want them to be
really dizzy). This will make the
journey to the classification
buckets a little more challenging
(and much more entertaining to
watch!).
Activity 3 – If you can sing
about it, you can remember it.
This activity introduces students
to some gymnosperm songs.
Putting names and characteristics
to simple tunes can help in
memorization.
Set Up and Materials
Make photocopies of the
Gymnosperm Songs sheet.
Playing the Game
· Have students sing the songs.
The songs may seem silly, but
they’re supposed to be silly. The
more effort that you put into it,
the less reluctant the students will
be to sing.
· Later in the unit, when students
are preparing for presentations
that they will give on a specific
genus, suggest that they create
their own songs. They might want
to use easily-recognizable tunes
like She’ll be Comin’ Round the
Mountain, Row Row Row Your Boat,
or maybe they want to make up
raps, etc. Let the creative juices
flow.
Activity 4 –Gymnosperm Trading
Cards
This activity can be on-going
throughout the unit. It will
encourage students to think about
phylogeny and gymnosperms
outside of the set class time.
Set Up and Materials
A template for the Trading Cards
is provided in the following pages.
Make photocopies so you will have
extra sets of cards. Just trim the
edges of the paper, fold the sheet
in half length-wise (so that the
picture of the plant is on one side
and the description on the other)
and laminate.
Playing the Game
Hand out trading cards as a type
of reward for helpful behavior,
outstanding performance on a quiz
or homework assignment, etc.
Once a student obtains a certain
number (5, for example) of
different trading cards, he/she
may cash them in for something
(extra credit points, homework
pass, etc.)
These cards may also be useful
when students are identifying
species in the classroom or in the
field.
Feel free to make your own
additional trading cards or have
the students make them.
Gymnosperm Songs
To the tune of “BINGO”
There was a spruce tree, had a name, and Picea was its name-ea
P-I-C-E-A, P-I-C-E-A, P-I-C-E-A and Picea was its name-ea.
There was a fir tree, had a name, and Abies was its name-ees,
A-B-I-E-S, A-B-I-E-S, A-B-I-E-S, and Abies was its name-ees.
There was a pine tree, had a name, and Pinus was its name-us,
P-I-N-U-S, P-I-N-U-S, P-I-N-U-S, and Pinus was its name-us.
There was a hemlock, had a name, and Tsuga was its name-uga,
T-S-U-G-A, T-S-U-G-A, T-S-U-G-A, and Tsuga was its name-uga.
And so on for other genera with 5 lettered names.
Abies
To the tune of “Yesterday”
Abies,
Scales with seeds falling off of me,
I’m not half the cone I used to be,
Oh scales with seeds, are leaving me….
Suddenly,
Upright axes stand alone,
They don’t even look like cones,
Oh I believe, in Fir trees
How are
Leaves attached to the twig, they aren’t real big
I see
Rounded scars, where the leaves have made their mar-r-r-ark,
Abies,
You always make such lovely Christmas trees,
But sometimes you are sti-icky,
Oh I believe in fir trees.
Mm-mm-mm-mm-mmm
Pine Trees
To the tune of “I Like Big Butts”
I like pine trees and I can not lie,
You other botanists can’t deny
When a cone hangs down with woody scales in place
And those fasicles in your face
You get Pinus
Wanna get wood from that tree
But can’t give it away for free
For my house I used that lumber,
And for the bed in which I slumber,
Oh, Pinus, I wanna get with ya,
And take your picture,
So fellas (yeah) fellas (yeah)
Has your conifer got the bundles (heck yeah)
So shake ‘em, shake ‘em, shake those bundled leaves
Pine trees are great
Spruce
To the tune of “She’ll be Comin’ Round the Mountain”
Spruce will spin between your fingers when you try,
Needles spin real well when they have more than 2 sides,
But don’t stick the end of that needle
In your hand or other people
Else you’ll have no one to love you
When you die
Yee-haw!
Juniper
To the tune of “She’ll be Comin’ Round the Mountain”
Some junipers species have two types of leaves,
Some look like scales and some may be skinny,
But before you head for home
Take a look at those strange cones
They’re blue and waxy and look like small berries
TRADING CARDS (all information is from Forest Trees of Maine 1973 Edition)
Eastern White Pine
(Pinus strobus)
· grows best on fertile, well-drained soil
· bark of young trees is smooth and thin, green with
a reddish brown tinge, or brown in spots. Bark of old
trees is 1-2 inches thick, very dark, and divided into
broad, flat ridges
· leaves are in clusters of 5 (think 5 letters in the
word white, 5 needles/bundle), are flexible, and are
3-5 inches long
· cones are 4-8 inches long, cylindrical and borne on
a long stalk. They take 2 years to mature and open
to discharge seeds in late August through
September
· usually 70-80 feet tall
· State tree of Maine
herba.msu.ru/pictures/Dietrich/pages/617.htm
Red Pine
(Pinus resinosa)
· grows on dry, rocky ridges or light, sandy soil
· grows to 60-80 feet tall
· bark is divided into broad, flat ridges
· leaves are in clusters of 2, are 4-6 inches long,
dark green, soft and flexible. They break cleanly, at
a sharp angle, when folded between your fingers
· cones are egg-shaped, about 2 inches long, borne
on short stalks
· called red pine because it has reddish bark and
pale red heart wood
http://www.borealforest.org/trees/red_pine.jpg
Pitch Pine
(Pinus rigida)
· grows in sandy barrens or plains and on gravelly
soil of uplands
· branches are horizontal, rigid, and contorted
· grow to 30-40 feet tall
· bark is rough, irregularly divided, and is dark gray
or reddish brown
· leaves are in clusters of 3 (think of pitches in
baseball…3 strikes and you’re out!)
· leaves are 3-5 inches long, dark yellow-green,
stiff, and stand at right angles on the branch
· cones need 2 years to mature, are 1 ½ inches long
and are not very noticeable
· cones can remain on trees for 10-12 years!
· a sharp, rigid curved prickle is produced on the tip
of each scale of the cone
· cones open gradually in mid-winter
http://departments.bloomu.edu/biology/ricketts/Pin
us/P_rigi/pics/P_rigi_mat_cone1tn.jpg
Jack Pine
(Pinus banksiana)
· grows on sandy, rocky, shallow acid soils
· branches are long and flexible
· grows to 50-60 feet tall
· bark is dark brown with a hint of red, thin with
irregular rounded ridges
· leaves are in clusters of 2, are ¾ - 1 ½ inches long
· cones are very curved
· scales have tiny prickles that often fall off
· cones may stay on tree for 12-15 years
http://www.nyflora.org/trips/FlatRock_2003/Pinus_
banksiana_branch_Gadway_NYFA_trip_080903c_G
JE.jpg
Tamarak
(Larix laricina)
· commonly found in cool, swampy places but can also
grow on well-drained soil
· grows to 50-60 feet
· bark separates on surface into small, thin,
irregular scales of a reddish brown color
· leaves are linear, about 1 inch long, 3-sides, and
borne in clusters of 8 or more on spurt
· leaves are bright breen and turn yellow in
September just before they fall off
· cones are small, spherical, ¾ of an inch long, and
borne erect (standing up straight) on stout stems
http://botit.botany.wisc.edu/courses/img/bot/401/
Coniferophyta/Pinaceae/Larix/Larix%20laricina/You
ng%20seed-cones%20detail%20EP%20.jpg
Black Spruce
(Picea mariana)
· common on cool upland soils and frequently grows
along streams and on borders of swamps and bogs
· grows to 70 feet tall, although in bog might only be
6-8 feet tall
· branches are short, hang down, and may curve up
at the end
· lower branches may touch the ground and form
new trees
· bark is grayish brown
· leaves are ¼- ½ inch long, dull blue-green, bluntpointed, flexible, soft to touch
· cones are ½ - 1 ½ inches long with stiff scales and
toothed edges
· twigs have hair
· spruce beer is made by boiling the branches
http://www.mntca.org/Reference_manual/Images/Pi
naceae/Picea/picea%20mariana%20-%20nice%20%20cones,%20needles%20-%203-8.jpg
Red Spruce
(Picea rubens)
· grows in well-drained, rocky upland soils,
particularly on the northern side of mountain slopes
· grows to 60-80 feet tall
scales of irregular shape
· leaves are dark green with a yellow tinge and are
very shiny
· leave are about ½ inch long, sharp-pointed, stiff,
and prickly to the touch
· cones are oblong and are 1 ½ - 2 inches long
· ripe cones are reddish brown and are shiny
· cone scales are stiff
· cones drop from tree in the autumn or early winter
and are completely gone from the branches by the
following summer
· shade tolerant
· twigs have hairs
http://www.fmnh.helsinki.fi/nayttelyt/ktp/sisalto/k
umpula/Picea_rubens.jpg
White spruce
(Picea glauca)
· grows on shallow, rocky sites and is often found in
old pastures or cleared land
· unable to tolerate shade
· grows to 60-90 feet
· bark on old trees has light grey, plate-like scales
that are thin, irregular, and with a somewhat
brownish surface
· leaves on lower side of branches are often bent
upward so that they are actually on the upper side
· leaves are pale blue-green at first and later
become a dark blue-green
· the leaves give off a strange odor that leads some
to call it the “cat spruce” because of the odor’s
similarity to the smell of cat urine
· the cones are slender, cylindrical in shape, pale
brown and shiny when ripe, and usually about 2
inches long
· cones ripen in August and September and give
seeds until October
· cone scales are thin and flexible and collapse easily
when the cone is clasped in your hand
· the twigs are hairless
http://www.mntca.org/Reference_manual/Images/Pi
naceae/Picea/picea%20glauca%20-%20good%20%20cones,branchlet%2012-15-04.jpg
Eastern Hemlock
(Tsuga canadensis)
· grows best on moist, cool sites
· grows to 60-70 feet
· the tip of the tree droops down a bit and often
bends to the east
the bark is divided into narrow, rounded ridges
covered with thick scales and varies in color from
cinnamon-red to gray; bark exposed by cuts or
bruises looks purple
· leaves are flat, tapering, generally rounded at the
tip, 1/3 – 2/3 inches long
· leaves have a distinct short petiole (leaf stalk) and
are arranged so that the twig looks flat
· leaves become shorter towards the tip of the twig
· leaves are dark yello-green with a shiny upper
surface and whitish under surface
· cones are about ¾ of an ince long, oblong, light
brown, hang down, and are suspended on short,
slender stalks
· cones mature during the first autumn and usually
stay on the branches unil the next spring
· twigs are very fine and flexible
http://botit.botany.wisc.edu/courses/img/bot/401/
Coniferophyta/Pinaceae/Tsuga/Tsuga%20canadensis
/T%20canadensis%20cones%20MC%20.jpg
Balsam Fir
(Abies balsamea)
· common in damp woods and well-drained hillsides
· grows to 60-70 feet tall
· bark on young trees is pale gray, smooth, thin, and
has prominent blisters that are filled with a resinous
liquid known as “Canada balsam”
· leaves are flat, about 1 inch long, pitchy, dark
green and shiny on the upper surface and whitish
below
· tips of leaves are usually notched
· leaves on top branches turn up, but leaves on lower
branches spread out at right angles to the branch,
giving it a flattened appearance
· cones are 2-4 inches long, erect and dark purple
before maturity
· cones ripen in August and September of the first
year, disintegrate shortly after, and leave the
central axis standing on the twig
· winter buds are covered with a clear resin
· a favorite for Christmas trees and greens
http://www.conifers.org/pi/ab/balsamea1.jpg
Atlantic white-cedar
(Chamaecyparis thyoides)
· grows in bogs or low areas along ponds or streams
· grows to about 40 feet tall
· tree has a conical shape
· bark is fibrous, grayish to reddish brown, usually
spirally twisted
· bark on young trees is easily pulled off in strips
· leaves are bluish-green, scale-like, and arranged in
somewhat fan-shaped clusters
· leaves give off an aromatic odor when crushed
· cones are small, round, smooth and purplish before
maturity, about ¼ of an inc in diameter, and persist
through the winter but are not very noticeable
http://www.conifers.org/cu/ch/thyoides2.jpg
Northern white-cedar, Eastern Arborvitae (Thuja occidentalis)
· generally found in swamps, along streams,
mountain slopes, and old pastures where soil is moist
· trees grow to 60 feet tall
· bark is reddish brown, maybe tinged with orange,
and has shallow fissure, which divide into flat narrow
ridges
· leaves are opposite or two-ranked, usually about
1/8 inch long, scale-like, blunt, and arranged so that
the small branches are flat in shape
· leaves have a pleasant, aromatic odor and a nice
taste
· cones are erect, small, about ½ inch long with only
a few pairs of scales
· cones mature in one season
http://keiriosity.com/cupressaceae/thuja_occidenta
lis.jpg
Eastern redcedar
(Juniperus virginiana)
· grows on poor soils, gravelly slopes, rocky ridges,
and moist, sandy ground
· gets the name “redcedar” from the red color of
the heartwood
· grow to 30 feet tall
· bark is light brown, tinged with red, and separates
into long, narrow shreds on old trees
· leaves are scale-like, overlapping, about 1/16 inch
long, dark green, and stay on the tree 5-6 years
· leaves grow hard and woody the third season
· branchlets are 4-sided
· current growth and fast-growing shoots have
leaves that are narrow and taper at the ends to
sharp points
· the cone is berry-like, globose (globe-shaped), 1-2
seeded, pale green at first and then turning dark
blue when ripe and is about the size of a pea
http://www.richmond.edu/~jhayden/conifers/junipe
rus_virginiana_5s.JPG
Common juniper
(Juniperus communis)
· found commonly as a shrub in pastures and waste
open places on shallow, rocky soil
· bark is grayish brown and occurs in thin,
longitudinal, shreddy layers
· inner portion of the bark has a reddish tinge
· leaves occur in whorls of 3 and are sharp, stiff,
dagger-like, and persist for several seasons.
· leaves are ¼ to ¾ inch long
· upper surface of leave is concave (curved inward)
and marked with a broad, white line
· the underside of leaves is dark green
(because of the bending of the twigs, the underside
of leaf actually appears to be the upper side)
· cone is dark blue, covered with a thin bloom,
slightly smaller than a pea, has a strong resinous
taste, and stays on the tree during the winter
· male and female parts are found on separate trees
http://www.funghiitaliani.it/Alberi/Ginepro%20comu
ne/Juniperus%20communis1.jpg
FIELD DAY 1
Before embarking on the first
field day, you should give the
students a summary of what they
will be doing in the field. Some
students may be distracted by
being outside. Giving specific
details and instructions of what to
do in the field will hopefully help in
increase students’ concentration.
Provide the students with safety
guidelines and require that they
dress appropriately for being in
the field. Being unsafe or
unprepared may give a student a
negative impression of field work.
Safety suggestions are included in
the following pages.
You may need to obtain permission
slips, arrange for a bus, etc., if
your field site is not on the school
grounds. Please take appropriate
action to ensure that your entire
class will have a successful session
in the field.
Make appropriate arrangements
for students needing special
accommodations. For example, you
may need to choose a field site
with even, clear ground; bring
another adult to assist a particular
student; make sure than any
students with allergies (bees,
poison ivy, etc) bring their
medications
Summary
What gymnosperms can we identify
in the outdoors?
The first field day is an
introduction to the outdoor
classroom. Students should
become aware of how to interact
safely and respectfully with the
natural environment. They will use
the knowledge of gymnosperms
that they have built in the
classroom to survey gymnosperms
in the local area.
Objectives
Students will:
· follow safety rules
· identify gymnosperms in the local
area
Materials
· Dichotomous Keys that students
made during the Dichotomous Key
activity
· a pencil
· blindfolds
· first aid kit
· appropriate clothing
· field guides (some suggestions
are listed under Resources)
· cameras (if desired)
· students should bring notebooks
and pencils
· hand lenses or magnifying glasses
· photocopies of the
Identification Quiz
Setting
Outdoors! Choose a local area that
has good gymnosperm diversity.
The site will preferably be within
walking distance of the school, as
you will be visiting the site more
than once.
Duration
Stay out there as long as you can!
and learning in a different
environment.
Refer to the Getting to Know the
Gymnosperms background reading
for a review.
Procedure
Warm Up
Before going outside, make sure
the students understand the
safety rules and know what is
required of them while they are in
the field.
Making Connections
This is a great opportunity to show
students that learning is not
limited to the indoor classroom. It
is an introduction to the outdoor
classroom. Becoming familiar with
gymnosperms in the local area will
give students a greater
understanding of the plants and
will hopefully encourage them to
seek out other places where they
can find gymnosperms.
The Activities
Teacher Tour
Background
Observing and identifying
gymnosperms in the natural
environment is very important to
building the students’ appreciation
and knowledge of this group of
organisms. The field days should
be focused on increasing students’
knowledge, but should also
emphasize the fun of being outside
1. Sit the students down in a circle
at the field site.
2. Show the students a pencil that
you brought with you.
3. Give the students the following
instructions:
· They will close their eyes and you
1. Give the students an orientation
to the field site. Tell them about
the history of the area, your
reasons for choosing the site, what
types of plants they can find
there, where the site is in relation
to the school, etc. Students
should record this information in
their notebooks.
Observation Exercise
will hide your pencil somewhere
within a 10-foot radius of the
circle (or inside the circle). They
will have 3 minutes to try to find
the pencil. If they find it, they
must not touch it. They must leave
it where it is and not tell anyone
that they have found it – just
observe its location and walk slowly
back to the circle and sit down.
4. Have the students close their
eyes. While their eyes are closed
(and not peeking!), put the pencil
behind your ear.
5. Tell the students to open their
eyes and begin searching.
6. After the 3 minutes of
searching is up, call all of the
students back to the circle.
7. Find out how many students
located the pencil.
8. Reveal the location of the pencil
to the rest of the students.
Discuss the importance of careful
observation. Also point out the
fact that everything has a place –
a pencil is more likely to be found
in someone’s pocket or behind
their ear than up in a tree or under
a rock.
Meet a Tree
1. Pair up the students.
2. One student (student A) of the
pair blindfolds the other (student
B).
3. Once student B is blindfolded,
student A leads student B to tree.
4. Student B needs to find out
whatever he/she can about the
tree that he/she has been led to
(without actually seeing it). This
may include hugging the tree to
observe its diameter, feeling the
texture of the bark, picking up
leaves or cones from that tree.
5. When student B is finished
making observations, he/she is led
away from the tree by student A.
6. The blindfold is removed and
student B must find the tree that
he/she observed while blindfolded.
7. Student B must make a guess of
what type of tree he/she
observed.
8. The partners switch roles and
repeat the activity.
* Make sure that students are not
hugging trees covered in poison ivy!
Family and Genus Identification
1. Give each student a copy of the
Identification Quiz and a hand
lens.
2. Lead the class to a tree of your
choosing.
3. Using the dichotomous keys
that they made during the
Dichotomous Key classroom
activity, students must determine
the family and genus of the tree.
They must provide both the
common and scientific names.
4. Repeat for several other trees
of your choosing.
Species Identification
1. Students must identify at least
two gymnosperms to the species
level using field guides.
2. Students must record the
name and a short description
and/or drawing of the plants that
they identified.
3. If students brought cameras,
encourage them to take photos of
the plants.
Wrap Up
· Go over the plants that were on
the identification quiz and those
that the students identified to the
species level. Make sure that all
students are comfortable
identifying plants in the field.
Tag a Tree
This is just a little simple activity
that can be done at any point
during the field days.
1. Call out a family, genus, or
species that the students must
find quickly and tag. For example,
if you call out “Picea!”, students
should immediately run to a spruce
tree.
2. Repeat as many times as you
want.
3. You could turn this into a
competition by stipulating that
students that tag the wrong plant
are “out” or the last student to tag
the correct plant is “out.” You may
want to reward the winner with a
Gymnosperm Trading Card, extra
points on the identification quiz,
etc.
Assessment
· Grade the Identification Quiz.
· Give the students a safety
review quiz (written or oral) that
reviews the safety rules for the
field days; or have them act out
the safety rules and the
consequences of not following
them.
Extensions
· Ask students to identify one or
two gymnosperms in their
neighborhood.
Resources
· Maine Forestry Department’s
Forest Trees of Maine
· Tree Finder – A Manual for the
Identification of Trees by Their
Leaves by May Theilgaard Watts
· Fandex Family Field Guides –
Trees by Steven M.L. Aronson
· National Audubon Society’s Field
Guide to Trees
SAFETY GUIDELINES
The following page was taken from Project Learning Tree’s “The Changing
Forest: Forest Ecology” guide. It details field trip safety guidelines.
Students should be given a copy of this and should read it thoroughly. It is
also a good idea for your students to actually write down the safety rules
for themselves. That way, there can be no excuses that they have not read
or understood the instructions. If the students are involved in creating a
set of class safety guidelines, then their list may actually turn out to be
more detailed than the guidelines provided here.
Here is a summary of what to wear and bring on the field days:
- Sturdy walking shoes that can get dirty (no flip flop, high heels,
etc.)
- Comfortable clothing (preferably long pants and long sleeves to cut
down to bug bites, scrapes, poison ivy, etc.
- A hat with a brim (this will protect you from sun, spider webs,
branches, etc.
- sunglasses (if going to a sunny place)
- sunscreen
- water bottle
- bring bug repellent
- small bag/backpack with a notebook, pencil, and other supplies
needed for note-taking and observation
and venomoussnakes.lf You are aft not presentin local Parksor
unsureof what may befoundin schoolyards.
your a.€a,ch€cka field guideor
contactlocal natural resource
-rnvestiSatingnaturecanbea
Poisonivy and Poisonoak are
naturccenters,or other
agencies,
I wonderfullearningexPeri
found growing on treesasa
Ience for studentsHowever' s;urcesfor information obtain
"hairy" vineor on the groundas
picturesof the harrnfulorgan
in natural environmentsmany
small-to medium-sized
Plants
plantsandanimalsarePresent ismsandlearnwheretheYare
with
Contact
leaves
three
with
ihat may beharmfulto students found to ensurcthat students
an
itchy
can
cause
form
either
or may b€harmedbYstudents' ar€awar€of potentialhazardsrash.If contactis noticed
hanto
how
discuss
In preparingfor an outdoorfield Youshould
quicklt the areaof contactcan
with bees,hoadleencounters
tdp, you needto takecertam
b€rins€dwith er'aterto Prevent
nets,andotherhazardsbefore
pr€cautlons.
the sprcadof oilsthat causethe
goingoutsrde.
Considertheweatherancl
do
r€action.ThoughsomePeoPle
postpone
To prevenldamageto Plants
trips
dressaccordinglynot se€mto havea rcactionto
andanimalsandenhance
Your
Mak€surestuin badrr'r'eather.
poisoni!./, they maydeveloPa
studentsto foltrip, encourage
dentshavePrcPer,sturdy
rcactionafter rcPeatedencounlow somesimPlerules:
if a long
footwear,€sPecially
terswith it. Therefore,
Poison
walk, or if rockYol mttddY
to
avoided
b€
should
ivy
Prevent
areasareinvolved.Studentsmay > Stayon Pathswhenever
of
a
Make
Droblems.
Point
possible
want to w€ara hat with a brim,
ihowing poisonivY to students
' suchasa baseball
> WatchwhereYouarewall(caP These
ing to avoidcrushingPlants when it is found outside.ManY
hatsprovideEoodProtection
thedifpeopledo not recognize
andanimals
frcm the sun;canProtectth€
may
which
i€rentformsof it,
> Do not Pickflow€rsand
facefrom spiderwebsor
vary seasonallY.
leavesunlessask€dto.
andwith a little insect
branches;
andother thorny
'ill
Gre€nbriar
see
to thebrim, can ) walk quietlysoYoui
aPPlied
repellent
or
bush€scancausescratches,
morewildlife.
helpkeepinsectsaway Lologne
in
the thornsmay getimbedded
oer^fumi,andhair sPraYshould > Do not litter.
skin.Bealvareof th€seandother
they attracl
not beworn because
whenwalking in the
branches
Many of the following
beesandotherinsects
in
arelikelYto occurin forest.Toavoidhitting PeoPle
to b ngafirst encountcrs
It is imPortant
go under
areasor less-traveled the fac€with branches,
if Youa.el€av wilderness
aidkit, especially
hold
onto
possible
or
when
them
areasIikelargeforestsor off-trail
ins schoolqroundsBasicfirst
next
the
Person
sites.Many of theseorganisms thebranghuntil
aii supplieishouldinclude
it.
line
takes
in
and taPe
gauze
fixs
rrrti
tirlf,lriP$ni*ir
-.
band-aids,
Pads,
(for larger scraPes);
Productsfor
(such as
bites
beestings or insect
Sting-eze,benadryl sPray,corlisonecream);and an antiseptic A
trianglebandageor AcelvraP
may be useful additionsto the
kit if you are going to a more
remotesite.For longer field tdPs,
bring water or have students
b ng waterbottl€s and a snack.
Beforegoing on the triP, identify common Plantsand animals
in your area that could be lmr.m
ful, such as poison ivy, Poison
oak, greenbria! bees,hornets,
-$* ule
uk;r
lr..
.*
e.
ttlr
ltf
p
E
F
F
F
*
g€es enrl Horneti
often, beesor hornetsnestin
old trees,underlogs,or €v€n
l^/ith
underground.Encounters
themcanbesuddenandunexpected.Remember
to beawareof
yout surroundings.Be€sare
oftenfoundin grassya.easur'ith
clovetor otherfloweas,so
watchwhereyou walk. If you
noticebeesflying in andout of
an area,avoidthat areaif possible.If theareacannotbeavoided
(for example,it is alongthe
path),try walking singlefile
slowly andquietlypastthe area.
Ifpeoplea.ealleryjcto bees,
keepthemat the front or endof
the line-never in the middle.It
may behelpfulto havean adult
at both the frcnt andbackof the
linewith a first aid kit, in case
thegroup must splitin half during thebeeencounter.
. lfbeesor hornetssudd€nly
apirearandstart ${arming, Sct
o.rto_lfthe
area.Beesandhornets
swarmaroundthe immediate
areagfthe hive.Theydo not
chaseafterpeople,sorunninga
away is all that is
shortdistance
necessary.
Explainto students
r /ith hornets
that encounters
may occursuddenly.
If someone
getsstungor seeshornets,yeli
for them to scatter.Thegroup
upon hearing
shor.d disperse
this,but shouldremainrr'ithin
sightofthe othe.groupmembers.oncethegroupis out of
the areaofthe swarm,gather
togeth€raway frcm thebeeor
hornetsiteand treatany stings.
and r$ing caution are the best
ways to avoid snake encounters.
l.+!-..JI!r:., i
If you areinvestigatinga log,
rememberthat hornetsand
snakesmay be found under or in
logs.Beforemovinga log, check
the surrcundingareafor signs
of ho.netsor otherhazards.
Avoidputting your handsin
holesor underlogs,because
you
cannotseewhat may bethere.
Whenrolling the log,hold onto
the top or sidesandroll it
toward your body.This action
will shieldyou from snakesor
hornetsby putting a barrier
you and th€m.Oncethe
betur'een
is
roll€d,
studentsmay go
log
aroundandinv€stigate
the ar€a.
to put the log backin
Snak€snormallyavoidpeople Remember
if theycan.Beingar{areof areas placebeforcleavingthear€a.
in y/hichsnakesmay befound
IDENTIFICATION QUIZ
Name
1. Family
Common name:
Scientific name:
Genus
Common name:
Scientific name:
2. Family
Common name:
Scientific name:
Genus
Common name:
Scientific name:
3. Family
Common name:
Scientific name:
Genus
Common name:
Scientific name:
4. Family
Common name:
Scientific name:
Genus
Common name:
Scientific name:
5. Family
Common name:
Scientific name:
Genus
Common name:
Scientific name:
Date
FIELD DAY 2
Summary
How much can I find out about my
genus?
During this field class, the
students will make careful and
detailed observations of plants in a
particular genus. The data that
they collect will be used to
understand a phylogenetic tree and
will also be used in their final
projects.
Objectives
Student will:
· determine the DBH (diameter at
breast height) of trees
· calculate tree height
· measure the crown spread of a
tree
· make detailed drawings of plants
with appropriate labels
· collect plant material for closer
inspection in the classroom
· identify plants to the species
level using field guides
Materials
· field guides
· photocopies of the Data
Recording Sheets
· tape measures
· clinometers (refer to the Forest
Measurement Guide for
instructions on assembly and use)
· students need notebooks and
pencils
· cameras (if desired)
· first aid kit
· appropriate clothing
· calculators (if doing calculations
in the field)
· plastic or paper bags for plant
samples
· hand lenses or magnifying glasses
· rulers
· if possible, a map of the field
site
· tape or string to use for marking
collected material
· markers or pens to write on
labeling tape
Setting
The field site
Duration
As long as possible! (at least 6080 minutes)
Key Terms
Clinometer
Diameter at breast height (DBH)
Crown spread
Making Connections
The students will gain useful skills
in various field techniques. It is an
opportunity for them to take an
active part in their learning and to
experience the work of a field
researcher.
Background
This field day is dedicated to data
collection. The quality of the work
they do on this field day will
effect the remainder of the unit.
Make sure that students are on
task and are making careful
observations.
Refer to the Forest Measurement
Guide from Project Learning
Tree’s “The Changing Forest:
Forest Ecology” for instructions
about measuring DBH, crown
spread, and observing tree damage
and signs of disturbance.
From this point forward, students
should focus their attention on a
certain genus. If your students
work well in groups, this can be a
group project. If not, make it an
individual project. Each student
(or group of students) should
either choose or be assigned a
genus of gymnosperm that is wellrepresented at your field site.
This is the genus that they will
focus on for the rest of the unit.
If a group of students has chosen
Pinus, for example, then that group
will closely observe as many
members of Pinus as they can
during this field class. They
should use field guides to identify
those plants to the species level
and should gather data on those
plants. Another group will be
collecting data on Picea, another on
Abies, and so on.
Procedure
Warm Up
· With the students’ help, make a
rough map of the field site. Make
photocopies of the map or have
each student draw the map on a
sheet of paper or in a notebook.
Students will mark the locations of
the plants that they study on this
map.
· Before going into the field,
review the safety rules and tell
the students what they will be
doing during this field class.
· Give the students copies of the
Forest Measurement Guide and
familiarize them with the
techniques they will be using
The Activity
Measurement Demonstration
Before turning the students loose
on the plants, demonstrate how to
measure DBH, tree height, crown
spread, and signs of disease and
disturbance. Ensure that at least
one member of each group is
comfortable with the techniques
before they begin to collect data.
Data Collection
1. Students should use the
resources that they have (rulers,
tape measures, field guides, hand
lenses, etc.) to complete a Data
Recording Sheet for as many
members of their genus as possible
in the time allotted. Sheets should
be complete with written
descriptions of plants, drawings,
measurements, and a map showing
the location of the plants.
2. Students should collect samples
from their plants to use during
later presentations or for viewing
more closely. They should label
their samples (with tape, string,
etc.) so that things don’t get mixed
up.
3. Make sure that you are
available to answer questions about
identification, how to use the
clinometer, etc. so that students
collect appropriate and accurate
data.
* You should decide how many
members of each species you want
the students to study (it is
probably best to observe more
than one, but you don’t want groups
spending the entire class looking
only at white pines.)
Wrap Up
· If there is time, play one of the
games from the Gymnosperm
Olympics or Field Day 1 (relay
race, tag a tree)
· Make sure that no one leaves
anything behind (water bottles,
measuring tape, backpacks, etc.)
· The Data Recording Sheets may
need to be completed in the
classroom. Help students to
calculate DBH, tree height, and
crown spread and give them time
to finish labeling their drawings
and other final touches.
Assessment
· The Data Recording Sheets can
be collected for a grade (if you
find that students have struggled
with the data collection or
calculations, make sure that they
understand what needs to be fixed
before moving on to the next part
of the unit.)
Resources
Project Learning Tree: The
Changing Forest: Forest Ecology
F o r e sM
t e a s u r e m e nGt u i d e
MEASURINGTREEDIAMETER
Once volr have identifi€d the v.lrious ti.re speciesin ;,cIrr arloptccLar.ca,nrrasurt a
6ioocrsunpre
of tach t)?€ (for.xirmplc, fivc ti€es per spcci€s).Use a tape measufe tlr lDeasurt tlrc circumfcr
ence ()f tlre tree at a standard lteight fronr the gft)und. For-estr:rs
usc thc rneasrrrcnrtnt dbh
diamttcr at breast hrig])t, wlich is about 4.5 ftrt ( 1.4I1l) abr)\,egroruld-.ls stQndircl. !\,ith the
circumfrrcncc data iD hitnd, fhe conversi()n to diametcr is sirnplc:
circumferencein in<hesdivided by 3.14 (n)=diameterin inches
MEASURING
TREEHEIGHT
i\lcastrriDg
hcighiis solrrc!/llri (lill'i(1rltiI) a clt'Dsc
Iirr'$1. BLrl\ ur canrstjn]ntchechai{htsryllcrc!'ou aar'r
scetlle tl.|:c's(:rowr)by usir)ga alirronreter.Vnl nlil)
l"rantk) aska folcstcr'
fo shorr voLrfsludcnlsh()rn/
lo
()r
rlsca pl()ftssioDal
clillonrclar. \ ou cr rlirka\'(\rr
own clilrol)xtcr bv usinll l pfofilctol ir strnl\,,s(xDc
'lrrrrll,.rntl.rinr.rllwriilrt rSarLrirdr.rl)l
-li)(lsc
(r) lind ir trtr'orrI ir'l) lcvcl
thc irlstruDlcnt,
grortttdartdslarullirr crrorigl)
awo', I(nn it t()scrllrc
Atlach rhe strawto the protractorwithtape,
A t t a c hr h es t r i n gt o t h e n r a w F . ( e a w e g h t o n
tol)ol tlx' trccl(x)kirr8throllgllthestrni! (l))bavca
t h e e n do f t h e 5 t r i n go s l n gt a p e
l)drlnrrstcadyilrc h(ight aD(lstringigilirrst(h('lx)trackn nnd rcndtbe nulnbcr h,hcrctha striig crlrsscs
thc pR)tfictor; (c)obtiirl A," lhc alrlilc of c)wation,by srrbtlactinil90 iionr tha rtunrb!'. r'clld(nr
thc pr()trdc{or,and kl) 1)avayo\rr pnrtrlcr iDeasurcin fcct thc lmrizoninl distirDcc"ab" from rvllcrc
you jtru to t lrc l)dsc(,f tlrlj lfc('
Note: llrf pn)tfaclor shcnrl(lbr hclcl
with the i 80' nlark ncxtto tlrr pcrson'sc!t.
Notes:
ThcsrdirccliolsilssLlmc
that voll arc lving down (n flat groulrdltyr lrvcl witlr the bascof
thc lrcc) anclkDking lllror-Lglrthc stral^r-If yoLrarc slalrdiDg,you will havc to add _\'(xrheightto lhr Iir)alcshuhtion io gul a nroreaccuri]te
rstilr]atidrot lhr trec'shcigllt.
Tllc trngcnt of 45' is 1. Hcncc,il lroLrarc rncasuringir I rfc ihat hdl)lxIs t(r llavea 45" anillc
l)ctwftn a and b.
ol-clcvDtion,
thc hcightof lhc trre r{ill beequalto tlredistance
;\s the hriglrt ol the irL'einucasrs, so doesthc angle of elcvir(ion. { | lrc gre ter tltt rrrgle ol
ek'vali()1r,
llrc B[calcrlh€lan:]cnt.)
BelirrlyoLrtr!' tlrisin the ficltl,],'ounrav rr;nl iol)racli.f b), rr srrringh.iglrtsofbuildinits
or oth.r tall objc.tsrear |orrr sdrool.
(xiItx6
la tnolE-cl rEAn
rirc TREE Th.changrng fore : For*rr6b9y
!r n.\1r,.1S.
F o r e sM
t e a s u r e m e nGt u i d e
By usingthc forrnulnab x TangentA = -Y,rr-con cklcrrrjnethc ltfighl ol tlrclrcc,rrllr'r.l
ab = the clistanccfront thc trec
A = lhe anglcof clevatiolr
X = the heightof fhc tfct
Tangentsaic determintdby Lr5;nglnrtt"nt ,ltirrt:j (5{:cthc cltaft lx.k)rv.)
Example 1:
ifab = 35 feel,anrlA = :lrt',thentllt tang.ntofA : 0.67,+.5
35x0.6745=X
l.t fcct,or 7.J nr)
23.61= X (tl1ehcighlis approxirnirldv
Exampl€2:
if ab = 3-5feetadd A = 60", thcr tlte trn*ent of,\ - L7311
3 5 x 1 . 7 3 2 1= X
60.62.J5= X (thcheiglltis app()xinlitclj,(' I ftct, oi 18.6nr)
CHARTiA = rllgle)
TANGENT
A
1"
2"
3"
4"
5"
6'
7"
8'
9"
'r
0'
l l'
12'
13"
14"
l5'
r 6"
17"
lB"
Tangent
0.0175
0.0349
0.0524
0.699
0.087tt
0.1051
0.122{J
0.I405
0.1584
0. r 763
0.194.+
0.2726
0.2309
0.2493
0.2679
0.2867
o.:tos7
0.3249
I9"
20'
21"
22"
23"
0..1443
0.:16,10
O.3839
0.40.10
0.4245
A
24"
'25',
')6'
'27',
Tangent
0.,14-51
0.466J
0.4877
0.s095
2rl" 0.5.t17
29' 0.5543
30
t).5774
3l'
0.6009
:12" 0.6249
,33', 0.649.t
34' 0.6745
-35" 0.7001
-J6'
0.726s
37' 0.7534)
3B' 0.7813
:J9' 0.BO9B
40' i).it391
41' 0.11093
42" O.9004
,r:J" 0.9325
44' 0.9657
45" 1.0000
46" 1.033-5
A
.t7''
,ltt'
'tt)'
50'
5 l"
5.1"
53'
5.1'
5i"
:i6'
Tangent
L07:,4
l.ll06
r.rl04
t.l9l8
1.2.t49
1.)79'
l..lt70
1.t764
r..l28l
1.4tll6
i 7'
1.5j99
58'
t.6003
5q'
60
6 t"
6t"
63"
64',
6J"
6d'
67'
6t]"
a,9'
L662t3
t.73)l
l.fr040
1.B807
] 96.1,6
1.050.1
2.1415
i.f46o
2.3559
2 4751
:1,.6051
A
;r)
;t
Tangent
1.;1;-;
.t.90,ll
t)
).\\;;7
;i
; t'
;5'
7(i'
7i'
78'
;9'.
irt).
llt'
8.t'
2.1;09
.l..lrr;,1
.i.;.J_11
+.010t1
4 . . j Jl 5
.1.7r).16
5.1446
5.6711
6 . . )l . ] r r
7.1154
[J-]'
ti.Il.l.]
84"
85'
u6'
87'
9.i l.r4
I 1.+-i0l
I+ .|O()7
19.OBr
I
88"
B9'
90"
2t].6:J6.1
5r-.29O()
unLlelincd
dnli'xtrson nr^-'tfis.
F o r e s tM e a s u r e m e nG
t uide
MEASURING
THECROWNSPREAD
Tb measrlrcth{] tr-cr'scror,vnol th€crorvn :jprcad(hora far
the bmDchesspl-eadarva-vfrol]r tl)e tfLrnk). rrscarr avera[je.
Findthc t)ra ch that sticksout the lafthcsiand ltirvctcaln
Inrnll)cr'\ slarrdLrnderii. Lln lhe oth€r sidt oFlhc t 11f, fil)d
thr branlh ihat sticksout thr fnrtlrrstnnd havestudtnt B
standon{lcrit. }lavcsillclfntssicl)itr lront ofthe (rtrrtks()
acl-oss
canbetakcn.IJirvcir teaDrnrambel
thc mc:,rsrrrct])cr){
lrttvrecrlthc iL,/osllrdcnts.I l)is is
rneasurc
th!'rlistaDce
croirynslfcirdal L])cwidcstl)oint.
Ncrt, firld tllr tl\,o brirrrches
on rachsidt thnt cl1(lr)ti:rcst
as brli)lf.
to tllc tacri )(l lclrcallhc sarlrcproce(llLrc
(listr
r)(( s lo lhd thc
D(tefnrirrcllla irvc[i]llcof lhesctlvo
cIlli"(ll
I,/IEASUNE
TFE I]ISTANCE
la;)suff t('ttt,
NeareslBranch
HE 0 STANCE
N'IEASURE
il
t.
TreeDamageand Signsof Disturbance
signs or sYmPtoms:
Damage cause by:
1
Ragfl.llIravrs l.ritlr lx)lfs
Lrscctslccrlirtgrrrtt lrt Jr'.rvLs
2
Bla(:koI l)folvn lcrvcs
Stfrrl (,r'lf.rl Llisclsr
3
Spotsor Dlrrnl)son lcnv.s
lnscctsJl]rl rnrles
4
li^ist(d or rllalforrlrrd lcilVrs
Inscrtsrt)rl Lliscnst,lrffl)i( idrs
5
t.rives chirrlllccolof brli)re IillL
'lilrrrk ()f
5
Briucll drcrl,
Llnharlcrl '(\rnds
7
l)ilr'k,lr(rl(sin thc bn''k
rr| bltrkr.'rr
ltcclirrg
(rI d.rrLrl.ic
T|u|]k woL||xi,cil kcf (lis..lsc,
a n u s c l()l y l ] l l l i r r s( ) rl n j n r i ] l s
8
l ) ) i r l r l ) f d n c l ) eo sn ( ) n {s i ( l f( ) lo r ) i ^ r n
l l o l r l( l ( ( l r r , f t x rilr l j L r r(vr I i n t ( . f r r r l s l e r r r
Llisrlsc,i)rs(ctnti,rali
9
Cilnkfr'(ir(l(i)(lscctiorr
ol il
(runk (n bfanch)
lirrrsirlirrlr'clior)s
'10Slrli(s
'12
llr( )l(fn l)fir(Jlcs
lk)ll!)h's
\'{irtff cnlffir)g t llfl)rulr o r,voLrrrds
atd suppoliing wo(xlrli'clrv Irr, lirrui
Intefnrl (lrcomp()sili(nr(il w(x)d l)\ lill)gi
13 [Lrngi tnLrs]rfoonrs
1 4 ( ; r ( r r rl . f , \ \ r . s l ' r. . , , n 1 ,
r(x)l daIllugr, dr()|lgllt, l\rlluti()
,,r1,..
Arr1"1 ,;.,'
DATA RECORDING SHEET
PLANT #
FAMILY:
GENUS:
SPECIES:
LOCATION (describe in words and mark the location on the map of the site)
CIRCUMFERENCE
DBH (DBH = circumference divided by !)
TREE HEIGHT
CROWN SPREAD
SIGNS OF DISEASE OR DISTURBANCE
DETAILED DESCRIPTIONS (drawings, photographs, written observations,
etc.) OF…
OVERALL SHAPE
CONES AND SEEDS
LEAVES
BARK
ANY ADDITIONAL OBSERVATIONS
PRESENTATIONS
After the students have completed their studies of a particular genus in the
classroom and in the field, they should present their findings. If your
students have been working in groups to research a genus, then this will be a
group presentation. If they have been working individually on genus
research, then it will be an individual presentation. The presentations might
take the form of making a poster, giving a PowerPoint presentation, designing
an educational brochure, etc. You and your class should decide on nature of
the presentations.
No matter what form the presentations take, as a minimum they should
include the following information about a particular genus:
· geographical distribution
· morphological descriptions (cones, bark, leaves, tree height, etc.)
· uses
· common species found at the field site
· examples of plant material (cones, bark, leaves)
SAMPLE RUBRIC FOR STUDENT PRESENTATIONS
EXEMPLARY
In addition to the
qualities of a GOOD
presentation,
· displayed a wide
knowledge of the
genus and its
characteristics
· demonstrated
extra care and effort
in the preparation of
presentation
materials
· provided additional
information about the
genus (beyond
descriptions of
morphology,
distribution, uses,
and common species
at the field site)
· engaged and
entertained the class
GOOD
· provided detailed
and accurate
descriptions of the
morphology,
geographical
distribution, and
uses of members of
the genus, and
described common
species at the field
site
· used plant
material to explain
important features
of the genus
· made eye contact
with the class
· spoke clearly
· material was
presented in a clear,
concise manner that
was easily followed
by the class
AVERAGE
· provided very
basic information
about the genus
· used very few
visual aids/plant
material
· occasionally made,
but did not maintain,
eye contact with the
class
· occasionally
mumbled or spoke
unclearly
· presentation was
fairly organized, but
could have been
improved
BELOW
AVERAGE
· provided very
basic information on
only one or two of
the following:
morphology,
distribution, and
uses of the
members of the
genus
· did not describe
the species found at
the field site
· presentation
materials were
sloppy and showed
very little effort
· did not make eye
contact
· did not speak
clearly
· presentation was
disorganized
POOR
· did not provide
detailed and
accurate
descriptions of any
of the following:
morphology,
geographical
distribution, and
uses of members of
the genus
· provided
inaccurate facts
· did not use any
visual aids (plant
material, pictures,
etc) to enhance the
presentation
· did not speak
clearly
· did not make eye
contact with the
class
· presentation was
disorganized and
difficult to follow
UNACCEPTABLE
· did not deliver a
presentation to the
class
SECTION 3
Putting It All
Together
PUTTING IT ALL TOGETHER
Summary
How are the gymnosperms that we
have studied related to one
another?
This lesson requires students to
analyze the currently accepted
phylogeny of gymnosperms and to
use their own data to explain the
phylogeny.
Objectives
Student will:
· understand a currently-accepted
phylogeny of the Pine Family
· map their own data onto a
phylogenetic tree
· think critically about
gymnosperm phylogeny
Materials
· photocopies of the Pinaceae
Phylogeny sheet
· butcher paper or poster board
· markers
· data that the students collected
in previous activities
· index cards
· tape
· photocopies of the Homoplasy
handout
Setting
Classroom
Duration
80 - 120 minutes
Key Terms
Parallelism
Reversal of character state
Making Connections
Compiling large datasets and
producing accurate phylogenetic
trees from multiple datasets
requires a lot of time and
specialized computer software.
For this reason, students will be
provided with a phylogeny and they
must use their knowledge to
explain the tree.
Background
The Pinaceae Phylogeny sheet
provides a phylogeny of Pinaceae
published in Molecular Biology and
Evolution in 2000. It is based on
combined sequences of 3 genes.
The Homoplasy reading provides
background information on
parallelism and reversal of
character states.
Procedure
Warm Up
Based on what they know about
gymnosperms, have the students
make predictions about the
relationships that exist among the
genera that they have studied in
Pinaceae.
Blowing up the Tree
Transfer the accepted tree of
Pinaceae phylogeny onto a large
surface such as a poster board,
butcher paper, or bulletin board by
painting it on, drawing it with
markers, or using some other
method so that the tree is very
large and easy to see.
The Activity
Mapping Morphological
Characteristics
1. As a class, create a deck of
index cards with characteristics of
gymnosperms on them. These
should include things like: leaves
needle-like, cones upright, two
seeds/cone scale, needles borne in
bundles, cones with overlapping
scales, leaves deciduous, etc. - the
identifying characteristics that
the students have observed in
their own study and
characteristics found in field
guides and other resources.
2. Map these characteristics onto
the large tree by taping the index
cards to the tree. For example, on
the branch leading to Pinus, you
should tape a card that has the
characteristic “needles borne in
bundles.” On the branch leading to
Larix, tape a card that has the
characteristic “leaves deciduous.”
The further into the tree you go,
the more general the
characteristics will become. You
can place actual plant material that
demonstrates these
characteristics, such as a bundle
of needles, or a cone with
overlapping scales, on the tree.
Mapping Biogeographical Data
1. Just as you did with the
morphological characteristics, map
biogeographical data onto the tree.
This does not have to be super
specific, but students should have
a general idea of what major parts
of the world these plants are
found in. Use categories such as
“North America,” “Japan,”
“Europe.”
Do you agree?
Now that the students have
mapped morphological and
biogeographical data onto the tree
made from molecular data, it is
time for them to take a step back
and decide if they agree with this
tree.
1. Remind students that any
phylogenetic tree is a hypothesis.
We will never fully understand how
organisms evolved and exactly how
they are related to one another.
The best we can do is gather as
much data as possible and make
educated guesses.
2. Lead a class discussion about
the tree. Ask questions like: Does
the tree make sense? What
relationships did you expect to
see? Which relationships were
surprising? Do the relationships
from molecular data agree with
the morphological data? What
genus is the sister group to Picea?
Are Abies and Pinus more or less
closely related to one another than
you expected? Do you see any
evidence of parallelism (read the
Homoplasy handout)?
Wrap Up
· Add the key terms to the word
wall
Assessment
Students should write an essay
detailing their thoughts about the
tree. They should address the
questions from the class discussion
and should provide reasonable
arguments for their responses. If
a student does not agree with the
relationships provided by the
molecular phylogeny, he/she should
propose an alternate tree.
Extensions
· There may be some genera on
the tree that the students have
not encountered yet. Encourage
students to research those genera
and explain their positions on the
tree.
· Have students find more
phylogenies of gymnosperms. They
will find one that includes the
Cupressaceae, or the Ginkgoaceae,
or the Cycads, etc.
Resources
· Molecular Biology and Evolution.
Wang et al. 17 (5): 773. (2000)
· Understanding Evolution:
http://evolution.berkeley.edu/
HOMOPLASY
Homoplasy is a term that refers to similarity due to parallelism or reversal
of character states. Parallelism is the separate origination of the same
character state in two or more organisms. You may hear this called
“convergent evolution.” The evolution of dorsal fins of sharks and dolphins is
an example of parallelism. Even though these animals may appear similar
superficially because they both have dorsal fins, they are not closely related
– one is a fish and one is a mammal!
Reversal of character state means that a character state has changed back
to the ancestral state. Think about the grillo evolution example presented
earlier in the unit. The evidence suggested that red and blue grillos evolved
from the extinct white grillo. Now you find a living species of grillo that has
white feet but shares other features with the blue grillo. The change of the
foot color from blue feet back to white feet is an example of reversal. This
can be confusing because you might think that this new grillo is actually an
ancestor of the blue grillo, when in fact it is the other way around.
Both parallelism and reversal can be confusing when building phylogenies.
Pinaceae Phylogeny
This phylogeny depicted here is based on combined sequences of three genes (matK, nad5, and 4CL). It is from a
paper published in Molecular Biology and Evolution in May 2000 by Xiao-Quan Wang, David C. Tank, and Tao Sang.
(The numbers on the tree are bootstrap percentages…they are beyond the scope of this curriculum)
SECTION 4
Sharing Your
Knowledge
THE FINAL PROJECT – SHARING YOUR KNOWLEDGE
This unit should conclude with a final project. The goal of the project is for
the students to share their knowledge of gymnosperms and their phylogeny
with others in the community. The following pages detail two suggestions
for final projects. You and your students may want to do one or both of
these, or you may decide to share your knowledge in a different way. Allow
the students to be creative and to communicate their knowledge in the best
way possible for them.
Suggestions:
1. Create a field guide to the field site
Students will compile the data that they collected in the field and in the
classroom to create a comprehensive field guide that can be used by
members of the school and local community. The guide should be organized
so that it is easy to use and helpful to someone visiting the area.
The guide should include an introduction explaining why the guide was made,
why the site was chosen, a short description of the site (location, size, etc.),
and a map of the site. The guide should also include a section explaining
what gymnosperms are and the relationships among the ones that the
students chose to study.
Students might want to include a dichotomous key that will lead readers to
detailed descriptions of genera and species. Pages on individual species
should include photographs, drawings, and written information.
Using published field guides as references for information and formatting
will be very helpful. However, make sure that the students’ field guide is
written in the students’ own words and really reflects what they have
learned about the gymnosperms.
This project can be integrated with an English class, Art class, Computer
class, or any other class that might improve the quality of the guide.
2. Create an educational tour of the field site
Students will develop an interactive and educational tour of the field site
for their families, peers, younger students, or other members of the
community. This is a way for the students to creatively share their
knowledge of the field site with others and to encourage members of the
community to learn about the local area.
The tour can be about 30 minutes to an hour long. It should include an
introduction to the field site and the reasons for creating the tour,
information about families, genera, and genera found at the site, and games
and other activities to facilitate learning. The students may choose to
incorporate some of the activities that they learned during the unit (like Tag
a Tree, Using a Dichotomous Key, etc.), or they may create something
entirely new.
Additional Ideas for Final Projects:
· PowerPoint presentations for other classes, families, friends, etc.
· Audio-tour of the field site
· Educational trail signs
References and Resources
Aronson, Steven. Fandex Family Field Guides: Trees. New York: Workman
Publishing Company, 1997.
Braus, Judy, ed. Ranger Ricks's NatureScope. Washington, DC: National
Wildlife Federation, 1992.
Campbell, Neil A., and Jane B. Reece. BIOLOGY. 7th ed. San Francisco:
Pearson Education, Inc, 2005.
Haley-Oliphant, Ann E. "Alice Huang: Microbiologist/Molecular Geneticist.”
Women Life Scientists: Past, Present, and Future: Connecting Role
Models to the Classroom Curriculum. Eds. Marsha Lakes Matyas and
Ann E. Haley Oliphant. Bethesda, MD: The American Physiological
Society, 1997. 231-239.
Judd, Walter S., et al. Plant Systematics: A Phylogenetic Approach. 2nd ed.
Sunderland, MA: Sinauer Associates, Inc, 2002.
Little, Elbert L. National Audubon Society Field Guide to North American
Trees. 23rd ed. New York: Alfred A. Knopf, Inc, 2000.
Maine Forestry Department. Forest Trees of Maine. 10th ed. Augusta, ME:
Maine Forestry Department, 1973.
Project Learning Tree. The Changing Forest: Forest Ecology. Washington,
DC: American Forest Foundation, 1996.
Slattery, Britt E., Alan S. Kesselheim, Susan H. Higgins, and Mark R.
Schilling. WOW! The Wonders of Wetlands. 6th ed. St. Michaels , MD:
Environmental Concern, Inc. and The Watercourse, 2003.
Theilgaard Watts, May. Tree Finder: A Manual for the Identification of
Trees by Their Leaves. Rochester, NY: Nature Study Guild, 1991.
Wang, Xiao-Quan, David C. Tank, and Tao Sang. "Phylogeny and Divergence
Times in Pinaceae: Evidence from Three Genomes." Molecular Biology
and Evolution 17.5 (2000): 773-81.
Websites:
Forest Trees of Maine: Softwoods. 2006. 30 Apr. 2007
<http://www.maine.gov/doc/mfs/pubs/ftm/ftm_sw.htm>.
Irving Forest Discovery Network. Ed. Jeff White. J.D. Irving, Limited. 30
Apr. 2007 <http://www.ifdn.com/>.
Non-wood Forest Products from Conifers. 2007. FAO. 30 Apr. 2007
<http://www.fao.org/docrep/X0453E/X0453e00.HTM>.
Timme, Stephen L. "How to Construct and Use a Dichotomous Key." How to
Construct and Use a Dichotomous Key. 1997. Association for Biology
Laboratory Education. 30 Apr. 2007
<http://www.zoo.utoronto.ca/able/volumes/vol-12/7-timme/7timme.htm>.
Understanding Evolution. Ed. Josh Frankel. 2007. University of California
Museum of Paleontology. 30 Apr. 2007 <http://evolution.berkeley.edu>.
University of Hawaii Conifer Lecture. University of Hawaii. 30 Apr. 2007
<http://www.botany.hawaii.edu/faculty/webb/Bot201/Conifers/conifer_
lecture.htm>.
** Photographs and images not otherwise cited were obtained from Dr.
Christopher S. Campbell of the University of Maine.
EXTRAS
The following forms are used by a high school teacher in Maine. The
students use these forms to evaluate lessons and field trips and to evaluate
themselves.
FIELD TRIP EVALUATION
Name
Date
During the field trip, I was listening and/or working (none, very little, about
half, most, all) of the time.
Specifically, and science-related, what did you do?
Specifically, and science-related, what did you learn?
I (liked, did not like) the field trip because …
Write one science-related question resulting from the field trip.
Is there anything else you’d like me to know about the field trip?
LESSON/ACTIVITY EVALUATION
Name
Date
During today’s lesson/activity, I was listening and/or working (none, very
little, about half, most, all) of the time.
Specifically, and science-related, what did you do?
Specifically, and science-related, what did you learn?
I (liked, did not like) the lesson/activity because …
Write one science-related question resulting from today’s lesson/activity.
Is there anything else you’d like me to know about the lesson/activity?
INTERNET RESEARCH WORK FORM
Name
Date
I worked (none, very little, about half, most, all) of the time available.
Specifically, and science-related, what did you do today?
Specifically, and science-related, what did you learn today?
Write a “going further” or “wondering” or “want to know” science content
question about the information you found today.
List web sites/text pages/other resource pages “visited” and a brief
description of the type of information found there.
Is there anything else you would like to tell me or ask me?