E4-Beaks
WHICH BEAK IS BEST?
CORRELATIONS ALABAMA COURSE OF STUDY – SCIENCE 2005
Biology – 12, 16
Zoology - 7
Watch bird video.
Describe three methods of feeding that you observed.
a)
b)
c)
Compare your observations with your lab partner. Share with the group.
Introduction
Birds come in an almost infinite assortment of colors, habitats, niches, and behaviors. They also
come with an almost limitless variety of beaks. Some of their beaks are for ripping and tearing
flesh, as would be found on most predatory species, or catching insects on the fly, or cracking
seeds and nuts, or scooping fish from water. The list could go on and on.
In this activity you will explore the different kinds of beaks and how they affect feeding habits.
Materials (per group of 4)
1 “pincher bill” (clothes pin or similar)
1 “spoon bill” (spoon or similar)
1 “grabber bill” (hair clip or binder clip)
1 “pointy bill” (forceps, scissors or similar)
4 plastic cup “stomachs”
Stopwatch
Masking tape
100 paper clip “gem beetles”
100 toothpick “woody twigs”
100 dry macaroni noodles “crunchy critters”
100 rubber band “worms”
Lab instructions, data table, and graph paper
Bird field guide (optional)
Ruler or Meter stick
Safety
Observe standard rules of laboratory safety.
Competition may become great in Part 2. Be careful with the scissors and forceps not to injure
anyone.
Procedure
First, mark off a 50cm by 50cm area in the center of your table using masking tape. Make sure
everyone can reach it easily. This is the foraging ground. Food that gets knocked out of the area
has “escaped” and is off limits.
Revised June 2013
ASIM Biology: Evolution and Diversity
Page 1 of 5
E4-Beaks
Part 1 - Which beak is the best for each food?
1. Each group member should pick a beak (“pincher”, “spoon”, “grabber” or “pointy”).
2. Spread one of the "foods" on the table in an area within easy reach of each beak.
3. You will have one (1) minute to eat as much "food" as possible. You may use only
your “beak” to gather food. Hold your "beak" in one hand and your "stomach" in the
other close to your body.
4. At the end of one minute, count all the "food" items in your stomach and record
the totals in Data Table 1.
5. Repeat steps 2-4 using each of the other "foods".
6. Return all "food" to proper storage.
Part 2 - Bring on the competition!
1. Spread out a mixture of food containing about 100 of each of the different food
items.
2. In one (1) minute "eat" as much food, of any type(s) as possible.
3. After a minute of feeding count all the different food items in your stomach and
record in Data Table 2.
Revised June 2013
ASIM Biology: Evolution and Diversity
Page 2 of 5
E4-Beaks
Student Data Sheet
Which Beak is Best?
Name________________________________
Date _________________________________
Results:
Data Table 1
"Gem"
"Crunchy"
Beetles (paper
Critters
clips)
(macaroni)
Springy
Worms
(cut up rubber
bands)
Woody
Twigs
(toothpicks)
“pincher beak”
“spoon beak”
“grabber beak”
“pointy beak”
Data Table 2
"Gem"
Beetles
“pincher beak”
“spoon beak”
“grabber beak”
“pointy beak”
"Crunchy"
Critters
Springy
Worms
Woody
Twigs
.
Construct a bar graph of the average amount of food "eaten" by each beak.
ANALYSIS
Revised June 2013
ASIM Biology: Evolution and Diversity
Page 3 of 5
E4-Beaks
1. Which type of "beak" was most efficient for gathering the food source?
2. Why was that "beak" the most efficient?
3. Name a bird with a beak similar to the:
“pincher beak”
“spoon beak”
“grabber beak”
“pointy beak”
4. Explain how the shape of a bird's beak limits food supply?
Using your Bird Field Guide Complete the following chart: Choose any species of bird to represent
the family.
Family
Species
Food Source
Draw the beak
Duck like birds
Hawk like birds
Ground birds
Tree Clinging birds
Perching birds
Using the information from the above activitie formulate a hypothesis to the following situation:
The Galapagos island of Santiago experienced a year long drought. This resulted in much fewer
Revised June 2013
ASIM Biology: Evolution and Diversity
Page 4 of 5
E4-Beaks
small seeds with thin seed coats. The number of large seeds with thick seed coats was unaffected.
How did this phenomenon change the population of seed eating birds? What type of beaks would
you expect would be predominant in the next generation of offspring? Explain you answer based on
what you’ve learned today about beaks.
Revised June 2013
ASIM Biology: Evolution and Diversity
Page 5 of 5