Name___________________________________ Date _________________________Period __________
Evolution Review: Key
1. The process of the environment putting pressure on a species to change is called natural selection.
2. Darwin said that evolution occurred due to natural selection.
3. Darwin’s theory of evolution was influenced by Thomas Malthus’ theory that the human population
would grow out of control leading to overpopulation if unchecked.
4. Darwin was influenced by Charles Lyell who believed that geological processes occur very slowly and
that Earth must be millions of years old.
5. Charles Darwin explained how Natural Selection could cause could cause a population to adapt and
change over time.
6. According to Darwin, natural selection occurs due to:
a. Mutation
b. struggle for existence/survival
c. variations that exist in nature
d. some organisms are more fit for the environment
e. more offspring are produced than will survive
7. The individual does not evolve; the population evolves.
8. Darwin sailed around the world but did most of his studies on the Galpagos Islands. Each Island had a
different species of finch. This would suggest that all finches evolved from a common ancestor.
(Mutations / fitness) in DNA is/are the source of variation with a species. A “helpful” mutation
(increases / decreases) fitness of the individual in its environment, where as a “harmful” mutation
(increases / decreases) fitness.
10. The long neck of a giraffe is an example of a/an adaptation.
11. Fossils in the lowest sedimentary rock layers are older and simpler than fossils found in higher layers
of rock. This is an example of relative dating.
12. The youngest and most complex fossils are found in the top layers of rock.
13. The whale’s flipper and the arms of a human are examples of homologous structures because they
have the same bones but use them for different functions. They show evidence of a common ancestor.
14. The hip bones in whales and snakes are examples of (vestigial organs / homologous structures)
because they serve no function.
15. Analogous structures, such as the wing of an insect and the wing of a bird, have similar functions but
originate from different embryological structures.
16. All vertebrate embryos are (alike/ not alike) in that they all have similar patterns of development,
especially in the very early stages, which suggests a common ancestor.
17. An ancestral flock of finches flew from South America to the Galapagos Islands. They spread out and
adapted to all the different environments on the Islands. This is an example of gene flow due to natural
18. What is the difference between relative and radioactive dating?
Relative dating: age of a fossil is determined by comparing its placement with that of fossils in other layers of
rock. Paleontologists estimate the age based on the age of other fossils found near it.
Radioactive (absolute) dating: Scientists use radioactive decay to assign absolute (more exact) ages to rocks.
19. What is survival of the fittest? How does it apply to Natural selection? The individuals that survive to
reproduce more often have variations that are best suited to the environment (survival of the fittest). As the
environment changes, favored traits and allele frequencies will change, causing the
population to evolve.
20. Label each type of evidence for evolution:
similarities in embryology
D. fossil record- shows
suggests a common ancestor
same structure-different function
B. homologous structures C. vestigial
remnants of a common ancestor
that change has occurred
Match the scientists:
1. Lyell C
a. proposed the mechanism of Natural Selection
2. Malthus B
b. said human population increases faster than food
3. Darwin A
c. geologist who said the world was 4.6 billion years old
Evolution vocabulary (not all terms will be used, but you need to know them for the test!)
Gene Pool
Natural Selection
Vestigial Organ
Geographic Isolation
Homologous Structure
Artificial Selection
1. similar-looking organisms that can breed together and produce fertile offspring.
2. a slight inheritable difference seen within a species
3. process of long, slow change over time in a population
4. the success of an individual at surviving and reproducing in their environment
5. physical or behavioral traits that makes the individual more suitable to live in a
particular environment
6. change in genetic material, which leads to a source of variation in a species
Natural Selection
7. process in which nature selects those traits that are better able to survive to live the
longest and reproduce the most within a particular environment
vestigial organ (structure)8. remnants of homologous structures with no apparent function
9. evidence or remains of ancient organisms
artificial selection 10. Nature provided the variation, and humans selected those variations that they found
Helpful Adaptations: Define and give an example of each.
Camouflage: having a shape or color that blends in with the environment. Difficult for predators to see the prey Ex: snow owl in
Mimicry: having a shape or color that blends in with the environment. Difficult for predators to see the prey Ex: Viceroy butterfly
and monarch butterfly.