Introduction to Biology. Lecture 32
Alexey Shipunov
Minot State University
April 24, 2017
Shipunov (MSU)
BIOL 111
April 24, 2017
1 / 23
Outline
1
Where we are
Origin of seed plants
2
Jurassic park
From Triassic to Cretaceous
Jurassic and Cretaceous flora and fauna
Shipunov (MSU)
BIOL 111
April 24, 2017
2 / 23
Outline
1
Where we are
Origin of seed plants
2
Jurassic park
From Triassic to Cretaceous
Jurassic and Cretaceous flora and fauna
Shipunov (MSU)
BIOL 111
April 24, 2017
2 / 23
Where we are
Origin of seed plants
Where we are
Origin of seed plants
Shipunov (MSU)
BIOL 111
April 24, 2017
3 / 23
Where we are
Origin of seed plants
Life cycle of land plants
Sporic life cycle with interleaving generations
Diploid stage grow directly on the haploid stage and even
parasitizes on it (e.g., in mosses)
Originates from the life cycle of algae: diploid stage was an
adaptation to the distribution of spores
Eventually, diploid stage begin to dominate the life cycle
Shipunov (MSU)
BIOL 111
April 24, 2017
4 / 23
Where we are
Origin of seed plants
The conflict between size and reproduction
Competition for the light resulted in growing up; growing up
resulted in secondary thickening—trees appeared
Seed plants started as trees, and these trees were diploid stage
Haploid stage still existed and probably was a minute prothallium
This is a conflict: diploid stage cannot adapt better because free
haploid stage was too cranky, and birth control is impossible
Decision: take haploid stage on the diploid stage and grow it
inside
Shipunov (MSU)
BIOL 111
April 24, 2017
5 / 23
Where we are
Origin of seed plants
The seed
Seed is the chimeric organ of three parts: mother diploid tissue
(seed coat), daughter diploid (embryo) and female haploid stage
(endosperm)
Main problems: need for pollination, extremely slow growth (two
years in pine tree, up to five years in cycads)
Shipunov (MSU)
BIOL 111
April 24, 2017
6 / 23
Where we are
Origin of seed plants
Origin of seed I
spore
gametophyte (n)
sporangium
sporophyte (2n)
fertilization
Shipunov (MSU)
BIOL 111
April 24, 2017
7 / 23
Where we are
Origin of seed plants
Origin of seed II
male spore
male gametophyte
female spore
fertilization
female gametophyte
Shipunov (MSU)
BIOL 111
April 24, 2017
8 / 23
Where we are
Origin of seed plants
Origin of seed III
pollination
fertilization
seed with seed coat,
endosperm
and embryo
Shipunov (MSU)
BIOL 111
April 24, 2017
9 / 23
Where we are
Origin of seed plants
Three phyla of plants I
A
C
B
Shipunov (MSU)
BIOL 111
April 24, 2017
10 / 23
Where we are
Origin of seed plants
Three phyla of plants II
R!
2n
A
n
Y!
Y!
n
R!
R!
2n
B
2n
C
2n
n
2n
Y!
n
Shipunov (MSU)
BIOL 111
April 24, 2017
11 / 23
Jurassic park
From Triassic to Cretaceous
Jurassic park
From Triassic to Cretaceous
Shipunov (MSU)
BIOL 111
April 24, 2017
12 / 23
Jurassic park
From Triassic to Cretaceous
From Triassic to Cretaceous
Mesosoic era:
Triassic: starts 252 Mya
Jurassic: starts 201 Mya
Cretaceous: starts 145 Mya, ends 66 Mya
Shipunov (MSU)
BIOL 111
April 24, 2017
13 / 23
Jurassic park
From Triassic to Cretaceous
Triassic period
Pangea broke (part of Africa adhered to North America)
Climate becoming wetter
Grasshopper-like insects radiated
Synapsid reptiles declined, dinosaurs and pterosaurs appeared
Shipunov (MSU)
BIOL 111
April 24, 2017
14 / 23
Jurassic park
From Triassic to Cretaceous
Jurassic period
Atlantic ocean and Rocky mountains appeared
Peak of dinosaur diversity
Birds appeared as a lineage of small flying dinosaurs
In the sea, ammonites and primitive fish dominated
Shipunov (MSU)
BIOL 111
April 24, 2017
15 / 23
Jurassic park
From Triassic to Cretaceous
Cretaceous period
High level of water (second high after Devonian), warm climate even on
North and South poles, sea in North Dakota
Flowering plants appeared and rapidly colonized all land
Butterflies and flies appeared
Terrestrial dinosaurs slowly declined and finally disappeared in the very
end of period
Shipunov (MSU)
BIOL 111
April 24, 2017
16 / 23
Jurassic park
Jurassic and Cretaceous flora and fauna
Jurassic park
Jurassic and Cretaceous flora and
fauna
Shipunov (MSU)
BIOL 111
April 24, 2017
17 / 23
Jurassic park
Jurassic and Cretaceous flora and fauna
Terrestrial flora
Spermatophyta
Non-angiosperm seed plants (“gymnosperms”)
Magnoliopsida (angiosperms, flowering plants)
Pteridophyta
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BIOL 111
April 24, 2017
18 / 23
Jurassic park
Jurassic and Cretaceous flora and fauna
Archaefructus (discovered in 2002, Yixian)
Water plant with
very primitive
reproductive organs
Shipunov (MSU)
BIOL 111
April 24, 2017
19 / 23
Jurassic park
Jurassic and Cretaceous flora and fauna
Terrestrial fauna
Amphibia
Reptilia
Synapsida: ancestors of mammals, e.g., pelycosaurs
Anapsida: turtles and many extinct lineages like pareiasaurs from
Permian, now frequently united with diapsids
Diapsida: the most diverse reptilian group
Aves (departed from Diapsida)
Mammalia (in transition from synapsid reptiles to core mammals)
Shipunov (MSU)
BIOL 111
April 24, 2017
20 / 23
Jurassic park
Jurassic and Cretaceous flora and fauna
Reptiles, mammals and birds
Shipunov (MSU)
BIOL 111
April 24, 2017
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Jurassic park
Jurassic and Cretaceous flora and fauna
Subdivisions of reptiles
A Anapsid skull
B Synapsid skull
C Diapsid skull
Shipunov (MSU)
BIOL 111
April 24, 2017
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Jurassic park
Jurassic and Cretaceous flora and fauna
For Further Reading
Seed.
http://en.wikipedia.org/wiki/Seed
Reptiles.
http://en.wikipedia.org/wiki/Reptile
Shipunov (MSU)
BIOL 111
April 24, 2017
23 / 23