Where do new genetic variations come from? After a genetic variation exists, what would cause its frequency in the population to increase until it was fairly common?
What will be an ideal response?
A good answer will include the following key points:
• New genetic variations can result from spontaneous mutations and chromosomal crossover during the production of sperm and eggs.
• According to the principle of natural selection, the fate of these genetic variations depends on the environment.
• Specifically, in a given species living in a particular environment, some individuals with a genetically influenced trait tend to be more successful than others in finding food, surviving the elements, and fending off enemies—and are therefore better at staying alive long enough to produce offspring.
• As a result, their genes will become more and more common in the population, having been "selected" by reproductive success.
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Of the following statements, which is an accurate description of an infant's perceptual abilities?
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