Although elephants are far more distantly related to us than the great apes, they seem to have evolved similar social and cognitive capacities.

The intuitive connection children feel with animals can be a tremendous source of joy. The unconditional love received from pets, and the lack of artifice in the relationship, contrast sharply with the much trickier dealings with members of their own species.

Wild groups of chimpanzees attack their enemies like gangs. What they completely lack, precisely because of their strong territorial behavior, is a friendly relationship with their neighbors.

Empathy probably started out as a mechanism to improve maternal care. Mammalian mothers who were attentive to their young's needs were more likely to rear successful offspring.

Male bonobos really don't fit the human male ideal.

Popular culture bombards us with examples of animals being humanized for all sorts of purposes, ranging from education to entertainment to satire to propaganda. Walt Disney, for example, made us forget that Mickey is a mouse, and Donald a duck. George Orwell laid a cover of human societal ills over a population of livestock.

If both parties have a stake in the other, the chances of them killing each other are going to be reduced.