Evolution and Genetics Exam Study Guide
The accompanying geologic cross section below represents a cliff outcrop. Some bedrock
layers are labeled as millions of years old (myo). Letters A through E represent different
rock types
1. How old is layer C?
2. Is layer E younger or older than layer A?
3. Would it be accurate to say that section E is approximately 1.5 myo? Explain.
4. How do Earth’s tectonic plates relate to convection currents?
5. Which causes more of a change to a land surface, a lightning storm or a major
earthquake? Explain.
6. Looking at the picture above, describe why species 1 and 2 are different.
7. Describe natural selection.
8. Describe speciation.
9. How is isolation important to speciation?
10. What does mutation do to a population?
11. What is more important to a population overall, available resources, or chromosome
number? Explain.
12. Human embryos share similarities to other vertebrates. How does this relate to the
theory of a common ancestor?
13. If a mutant gene’s frequency is increases in a population through generations, what can
you infer about the gene?
Researchers discovered four different species of finches on one of the Galapagos
Islands. DNA analysis showed that these four species, shown in the illustration below, are
closely related even though they vary in beak shape and size. It is thought that they
share a common ancestor.
14. What factors would influence the differences in beak size?
15. What caused the organisms from South America and Africa to have the same genetics
in the picture below?
15. Differences in these bone arrangements suggests what about differences in
structures?