> You miss the point, why don't we have thousands of animals with the ability to hibernate that don't need them Because a tendency to hibernate is likely negat

> You miss the point, why don't we have thousands of animals with the ability to hibernate that don't need them Because a tendency to hibernate is likely negative for survivorship when it's not necessary - if lots of other animals are moving around and you aren't, then something is more likely to come and kill you. On the other hand, lots of animals have other varying traits that aren't obviously useful, but don't exact a significant enough toll to cause them to disappear. > But why would you already have the ability to hibernate efficiently if you don't need it Doesn't that assume that bears were transported into Canada and survived because they could hibernate? Isn't it perfectly possible that they moved further north gradually, increasing their tendency to sleep in cold conditions as they did so?