Download Speciation Book Worksheet

Name: _______________
Hr: _______
Isolating mechanisms are an important factor in SPECIATION. Speciation is the creating
of brand new species. (16-3)
1. List and define the three types of ISOLATING MECHANISMS.
a.
b.
c.
Charles Darwin visited the Galapagos islands around the year 1831. He paid close
attention to the birds (called finches) he saw on the island.
2. When the scientists Peter and Rosemary Grant measured beak size, feather colors, and
wing length, they graphed these numbers. What was the shape of their graphs? (p 407)
3. Why is beak size so important to the finches? How can it mean the difference between life
and death? (407)
4. What type of birds to big beaked finches tend to mate with? (407)
5. How did the finches get to the island? (408)
6. What was the isolating mechanism acting on the finch population?
7. True or False. Natural selection worked the same way with each finch population on each
island.
8. How might the difference in beaks (caused by natural selection) cause reproduction isolation
within the population?