Download Beaks of Finches

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Multiple Choice
1. Darwin's studies of finches on the Galapagos Islands suggest that the finches'
differences in beak structure were most directly due to
(1.) acquired characteristics in the parent finches
(2.) mating behaviors of the different finch species
(3.) the size of the island where the finches live
(4.) adaptations of the finches to different environments
2. Base your answer on the given information and statement.
Information: The Galapagos Islands in the Pacific were probably never connected to
South America. However, in the various habitats on the islands, there are about 14
species of finch-like birds that appear to be related to the finches on the South American
mainland. Although the Galapagos finches vary in beak structure, there is a close
resemblance between these species in plumage, calls, nests, and eggs. These species
do not interbreed and do not compete for food.
Statement: Isolation from the South American mainland and different habitats on the
Galapagos Islands are important factors in the production of new species.
(1.) The statement is supported by the information given.
(2.) The statement is contradicted by the information given.
(3.) The statement is not supported by the information given.
(4.) No relevant information is given regarding the statement.
3. Which situation would most likely result in the highest rate of natural selection?
(1.) reproduction of organisms by an asexual method in an unchanging environment
(2.) reproduction of organisms in an unchanging environment with little competition and
few predators
(3) reproduction of a species having a very low mutation rate in a changing environment
(4.) reproduction of organisms exhibiting genetic differences due to mutations and
genetic recombination in a changing environment
Please answer the following questions before we begin our lab
1. What examples of adaptations were evident in the finches of the Galapagos Islands?
2. Describe two factors that can limit the amount of competition between species in a
given area.
Use the evolutionary tree below to answer the questions 3 & 4.
Leaves
Buds / Fruits
Grubs
Seeds
Insects
Tool using finch
3. Which two organisms are more closely related? Explain
4. Which finch is the common ancestor to the finch that eats fruit and the finch that eats
insects?
Finch Lab Questions
1. Explain how this lab simulated the following concepts of natural selection.
a. variation
b. competition for resources
c. adaptation
2. How could finches have such different beaks yet come from the same ancestor?
3.
List the trait that we monitored in our finches and discuss its adaptive value.
4. Name two traits of finches other than beak characteristics and explain how they
contribute to the finches overall survival.
5. Explain how the "beaks of finches lab" completed in your class displays the Theory
of Natural Selection.
Read the following paragraph and use the diagram below to answer the questions
which follow below.
The medium ground finch is found on several of the Galapagos Islands. This species of
bird prefers to eat small seeds, which are easier to eat than large seeds. However, when
food is scarce, such as during a drought, some of the small ground finches can eat larger
seeds. The ability to eat larger seeds is inherited. The birds with thicker beaks crush
seeds more easily. Medium ground finches are least likely to be found on islands with
large producer populations, species of large ground finches, more variation in seed size,
and abundant rainfall.
Adaptations of Galapagos Island Finches (adapted from
Galapagos: A Natural History Guide)
1. Describe changes that would occur in the ground finch population during a long
period of drought when food is scarce.
2. Explain how this set of changes is an example of natural selection.
3. State one difference between the beaks of small ground finches and beaks of small
tree finches.
4. Would you expect the small ground finches and small tree finches to compete for
food on the island? Support your answer with evidence.
5. How is the beak of the cactus finch adapted to its feeding habits?
6. Which finch species is least likely to survive a severe drought that reduces the animal
population on the island? Support your answer.
7. Describe the most successful beak shape for eating small seeds.
8. In the past, a specific antibiotic was effective in killing a certain species of bacteria.
Now, most members of this bacterial species are resistant to this antibiotic. Explain how
this species of bacteria has become resistant. Your answer must include at least the
concepts of:
• overproduction [1]
• variation [1]
• natural selection [1]
• adaptation to the environment [1]