> Aside from the 'wow, intelligence', why is it that those of us with spines lack any 'computing power' in things like our arms? Are there any common sense reas

> Aside from the 'wow, intelligence', why is it that those of us with spines lack any 'computing power' in things like our arms? Are there any common sense reasons? I wonder if the fact that we can't grow them back is a factor. I could imagine that this would make it hard for us to evolve any sort of appendage intelligence that was important to our function.