From an evolutionary, survival-of-the-fittest perspective, one might think the shyer chipmunks were doomed. But Couchoux found that wasn’t the case. The less aggressive individuals took less risks, so they ate less, and they had fewer babies each year. But they tended to live longer. Less risk-taking meant fewer chances to be gobbled by an eagle. At the opposite end of the spectrum were the really bold chipmunks. “They reproduce earlier, they eat a lot, they take more risks. They will have more babies, let’s say three in one year. But then they die because they are eaten by a predator.
