1. Evolution Test Study Guide Answers

2. Adaptation Natural selection Coevolution Divergent evolution
Process leading to the increase in frequency of a particular structure, process, or behavior that makes the organism better able to survive and reproduce
Natural selection
Changes in inherited traits of a population over time
Changes help to increase the species’ fitness in its environment
Coevolution
Two species that live in close proximity changing in response to changes in the other
Divergent evolution
A number of species split off from a common ancestor
Convergent evolution
Evolution in different groups of organisms living in similar environments that produces species that are similar in appearance and behavior

3. Homologous structures
Gene flow
Movement of genes in and out of a population (migration)
Gradualism
Gradual changes of a species in a particular way over long periods of time
Homologous structures
Structures that have different mature forms but develop from the same embryonic tissues
Analogous structure
Structures similar in appearance and function but with different evolutionary origins
Embryology
Study of the anatomy of embryos and their development
Phylogenetic tree
Diagram used to show the evolutionary relationships between organisms and classify them into major taxa

4. Where did Darwin draw his ideas of natural selection?
Galapagos Islands
According to Darwin, evolution occurs because of what?
Because of natural selection
What causes variations in genotypes?
Mutations
Natural selection could not occur without genetic _variation_ in species.

5. Who proposed the idea of inheritance of acquired characteristics?
Lamark
What do scientists study when looking at biochemical similarities among organisms?
DNA sequences
What would affect the evolution of a species over time?
Resources in the environment and the offspring produced

6. Give an example of divergent and convergent evolution.
What would happen to the populations of the same species living in different areas?
They would evolve differently over time because of their different environments
Give an example of divergent and convergent evolution.
Divergent: beaks of finches on Galapagos Islands
Convergent: insect, bird, and bat wings
What type of population is most susceptible to loss of genetic variability as a result of genetic drift?
Small populations

7. Describe and give an example of geographic isolation.
When organisms are physically separated and form different species over time because of that separation
Butterfly species on the east coast and those on the west coast of the US
List all the conditions of the Hardy-Weinberg equilibrium.
Large population with no genetic drift
No migration
Random mating
No mutations
No natural selection

8. Explain reproductive isolation.
Organisms are able to mate but don’t because they live in different areas of the same habitat or in the same habitat but can’t breed because of polyploidy
Describe how speciation could occur as a result of geographic isolation.
One species gets separated into two groups by a barrier. The two groups look different from each other due to different environments.
What are the pieces of evidence for evolution?
Anatomy, embryology, biochemistry, paleontology

9. What is a vestigial structure and give an example.
Structure that had an important function in an ancestor species but no longer serves a function
Appendix in humans
How do fossils demonstrate evidence of evolution?
Shows ancient species that are similar to modern species
What is a transitional fossil?
A fossil of an intermediate stage in the evolution of species
What do similarities in proteins of different species indicate?
They share a common ancestor