27.2 Evidence of Evolution – Guided Reading
1. Define biological evolution
2. Fossil Evidence
a. What are fossils?
b. In what type of rocks are fossils found? How does this help humans date fossils?
c. What is a transitional link? Give an example.
d. Explain the difference between absolute and relative dating.
e. How do the geological timescale and fossils offer evidence of evolution?
3. Biogeographical Evidence
a. What is biogeography?
b. How does biogeography help explain why certain animals and plants are found in some
areas but not in others? Use an example in your explanation.
c. How does continental drift help to explain the uniqueness of biodiversity in the world’s
different biogeographical regions? Use and example in your explanation.
d. How many mass extinctions have there been in Earth’s history? What have been the
causes for these mass extinctions?
4. Anatomical Evidence
a. Define homologous structures. Give an example in your explanation.
b. Define analogous structures. Give an example in your explanation.
c. Define vestigial structures. Give an example in your explanation.
d. Explain the homology shared by vertebrates during embryonic development (use
Fig.27.9)
e. How was Darwin’s claim that whales (and dolphins) come from a land ancestor
supported by anatomical evidence?
f. How do homologous structures give evidence for evolution?
5. Biochemical Evidence
a. What do all living organisms share in common in their biochemistry?
b. How do scientists determine how closely two organisms are related using biochemical
evidence?
c. Which would have fewer DNA base sequence differences with humans – chimpanzees
or cows? Explain.
d. Why is evolution no longer considered a scientific hypothesis, but rather has
“graduated” into a scientific theory?