Have you not read textbook that explained specialized traits as reaction to the environment ? How could that be possible when these traits are needed immediately.
You miss the point, why don't we have thousands of animals with the ability to hibernate that don't need them ? Of course traits don't have to evolve rapidly if you already have them or don't need them. But why would you already have the ability to hibernate efficiently if you don't need it ? Why would a bird of prey evolve the ability to hunt from the skies at relative high speed before it can fly ? I'm sorry I read the books there are no legitimate answers. Like said I love science and technology.