Professor Davis suggests that genetic predispositions to normal bouts of depression contribute to survival and reproductive success by reducing the intensity of hostile urges and discouraging highly risky behaviors. The professor's suggestion best illustrates the perspective.

Evolutionary perspective

Explanation:According to this perspective some of our behavior have been inherited from our ancestors especially survival instinct behavior. We have certain survival ways of reacting to certainly situations that seem to threaten our survival and that how our ancestors survived .

Biological perspective

Explanation: with the introduction of the idea that evolution and genetics play a role in human behavior, the biological perspective seeks to determine the psychological aspects of human behavior by looking at evidence gotten from genetics and neurological studies. By studying the physical basis for human behavior, the reason and causes of most behaviors such as depression (a period of unhappiness or low morale which lasts longer than several weeks) can be ascertained.

the answer to your question is,

old stone age.

-mabel < 3