Comment by castle-bravo

I suspect that it's cultural and derives from our economic relationship to animals. I remember seeing a film as a child that depicted a native hunter killing a deer and profusely thanking the spirit of the deer; attributing intelligence and identity to the deer would predispose a hunter to pay close attention to the animal's behaviour and give him an edge in hunting it. In cultures with domestcated animals bred for compliance with human will, it is less advantageous to view the animal as another mind. Instead, we see them as tools to be used and discarded. To do otherwise would compromise our ability to extract maximum economic advantage from use of the animal.