BIOL102 Exam 1

Short Response Prep- Practice Questions

Can you pick out the mossy leaf-tailed gecko lying against the tree trunk in this photo? How is the appearance of the gecko a benefit in terms of survival? Given what you learned about evolution, natural selection, and genetic information in this chapter, describe how the gecko’s coloration might have evolved.

A typical prokaryotic cell has about inline style 3,000 genes in its DNA, while a human cell has about inline style 21,300 genes. About inline style 1,000 of these genes are present in both types of cells. Explain how such different organisms could have this same subset of inline style 1,000 genes. What sorts of functions might these shared genes have?

Based on the results of the mouse coloration case study, suggest another hypothesis researchers might use to study the role of predators in natural selection.

In a short essay (100–150 words), discuss Darwin’s view of how natural selection resulted in both unity and diversity of life. Include in your discussion some of his evidence. (For help in writing essays, see “Writing Tips and Rubrics” in the Study Area of Mastering Biology under “Additional Resources.”)

Describe how overreproduction and heritable variation relate to evolution by natural selection.

This honeypot ant (genus Myrmecocystus) can store liquid food inside its expandable abdomen. Consider other ants you are familiar with, and explain how a honeypot ant exemplifies three key features of life: adaptation, unity, and diversity.

Using at least two examples, explain how the process of evolution is revealed by the imperfections of living organisms.

What are the main sources of genetic variation in humans?

Explain how the individual is the unit of natural selection, but only populations can evolve.

Suppose that females of one population of strawberry poison dart frogs (Dendrobates pumilio) prefer to mate with males that are orange-red in color. In a different population, females prefer males with yellow skin. Explain how such differences could arise and how they could affect the evolution of reproductive isolation in allopatric versus sympatric populations.

Explain the role of gene flow in the biological species concept.

Is speciation something that happened only in the distant past, or are new species continuing to arise today? Explain.

Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian Islands have different elaborate courtship rituals. These rituals involve fighting other males and making stylized movements that attract females. What type of reproductive isolation does this represent?

Why is it necessary to distinguish homology from analogy to infer phylogeny?

Explain the logic of using shared derived characters to infer phylogeny.

Explain the concept of parsimony.

If you were to hike up Mount Kilimanjaro in Tanzania, you would pass through several habitats, including savanna at the base, forest on the slopes, and alpine tundra near the top. Explain how such diverse habitats can be found at one location near the equator.

Discuss how the distribution of a species can be affected both by its evolutionary history and by ecological factors. Could ongoing evolutionary change also affect its distribution? Explain.

Suppose humans introduced a species to a new continent where it had few predators or parasites. How might this lead to eco-evolutionary feedback effects?

More Ecology Materials. Be sure to understand:

• the BIDE model of population growth

• how demography can affect population growth

• what a community is and how it is shaped by ecological interactions

• the types of interspecific interactions

• what a keystone species is

• what an ecosystem is

• why it is important to conserve species AND their interactions