Lab 8 Evolution Lab Write Up
A. Galapagos Finch Evolution — HHMI BioInteractive Video
https:
www.youtube.com/watch?v=mcM23M-CCog
Answer the following questions after watching the film “Origin of Species: The Beak of the Finch”.
1. What are the two different theories as to why there are 13 different species of finches on the islands?
2. Which of these two theories is the co
ect one? What type of evidence proves that this theory is co
ect?
3. What is the definition of a “species” that is used in the film?
4. What are some different types of food eaten by finches on the islands?
5. What type of seed became scarce during the drought? What type of seed was abundant?
6. What is one way that finches identify others of the same species to mate with?
B. The Relationship of Beak Depth and Rainfall Part I.
Gray= red= 1976 Beak length
Black= 1977 Beak length
6A. What is the most common beak size of finches in 1976? _______
6B. Approximately how many birds had the most common beak size in 1976?_______
6C. Approximately how many birds had this beak size in 1977? ________
7A. What is the most common beak size of finches in 1977? _______
7B.Approximately how many birds had the most common beak size in 1977? ________
7C. Approximately how many birds had this beak size in 1976?__________
8. Using your answers for questions 6-7, what are two observations you can make from the graph in terms of ….
(1) number of ground finches and
(2) their beak characteristics in the years XXXXXXXXXX.
C. The Relationship of Beak Depth and Rainfall Part II.
The following table relates to Peter and Rosemary Grant’s data collected on Daphne Major in the Galapagos Islands as discussed in the video above.
Use the above information to explain why average phenotypic beak size oscillates overtime.
9. Why should you see an increase in beak size during periods of drought?
10. Why should you see a decrease in average beak size during wet years?
*Continued on the next page*
D. Bird Beak Adaptations
Examine the pictures of the different bird below and label the images below with their co
esponding letter. Which of the birds would be best adapted for each of the below feeding strategies?
Northern XXXXXXXXXXHouse XXXXXXXXXXGreat Horned Ruddy XXXXXXXXXXCormorant XXXXXXXXXXPa
ot XXXXXXXXXXSand Pipe
Flicker XXXXXXXXXXFinch XXXXXXXXXXOwl XXXXXXXXXXDuck
Bird Letter XXXXXXXXXXFeeding Strategy
________ consuming hard to crush large seeds
________ catching slippery fish
________ shoveling through wet sandy soil for inverte
ates
________ catching insects hiding in the bark of trees
________ tearing flesh from a rodent
________ consuming small soft seeds
________ probing for food sources in the mud