Chapter 3: Darwinian Natural selection

1.	Successful artificial selection, such as that practiced by plant and animal breeders to modify their crops and livestock, depends on which of the following? [Hint]
2.	List and briefly explain each of Darwin's four postulates. [Hint] To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
3.	Match each characteristic of Jones' and Reithel's snapdragons with its correct counterpart among Darwin's postulates. [Hint] Using the pulldown boxes, match each item on the left to the corresponding item at right. A. reproduction is nonrandom; organisms with favorable traits survive and reproduce better than others. B. some individuals are more successful and surviving and reproducing than others C. organisms vary D. variation is heritable Choice A Choice B Choice C Choice D 3/4 of the snapdragons had almost pure white flowers; 1/4 of the plants had yellow flowers.  [Hint] Choice A Choice B Choice C Choice D Flower color is determined by a gene with two alleles; SS and Ss individuals are white; ss individuals are yellow.  [Hint] Choice A Choice B Choice C Choice D Plants varied in the number of pollinator visits and seeds produced.  [Hint] Choice A Choice B Choice C Choice D White flowers attracted twice as many bee visits as yellow flowers.  [Hint]
4.	Based on their observation of the color preferences of the bumblebees visiting their snapdragons, Jones and Reithel predicted (and found) that the proportion of white-flowered plants _____ from the first to the second generation. [Hint]
5.	Adaptation is best defined as [Hint]
6.	Through their studies of medium ground finches, the Grants were able to demonstrate that, as a result of drought, [Hint]
7.	By studying medium ground finch populations over the course of several decades, the Grants and their colleagues have demonstrated that, during drought years, natural selection favors birds with _____ beaks; during wet years, natural selection favors birds with _____ beaks. [Hint]
8.	The effect of selection on individuals is [Hint]
9.	When selection acts on traits with heritable variation, the effects on a population will be [Hint]
10.	The evolution of new traits is possible because [Hint]
11.	The panda's "thumb" is actually a wrist bone modified by natural selection to perform a new function. This is an example of a(n). [Hint]
12.	Using beak shape in medium ground finches to illustrate, briefly explain the phrase "natural selection results in adaptation, not perfection." [Hint] To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
13.	Although the scientific community rapidly accepted that all organisms are related by descent, Darwin's mechanism for change over time -- natural selection -- wasn't fully accepted until nearly 100 years after the publication of The Origin. Which of the following explain(s) why? [Hint]
14.	The integration of modern genetics with Darwin's postulates is called the . [Hint]
15.	The creationist "argument from design" is based on the idea that complex structures and organisms can't arise by chance. The argument fails because, although _________ is random, ___________ is not; it is directed in the sense of increasing adaptation. [Hint]
16.	A key flaw of "intelligent design theory" is that it fails to recognize the importance of [Hint]
17.	Briefly refute the argument that, because speciation is too slow to be observed over human lifetimes, evolution is unprovable and therefore based on faith. [Hint] To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
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