I was driving home from work one day with my son. As we passed a squirrel that had been hit on the road and was presumably dead, I glanced in my rearview mirror and thought I saw him twitch. I immediately pulled over and walked back to the squirrel lying in the middle of the road. Sure enough, he was still alive. And with every passing car, moved ever so slightly with what little life he had left in him. I knew from past experience — my younger...