Anthropomorphism originally meant the attribution of human characteristics to God. It is curious that the word is now used almost exclusively to ascribe human characteristics--such as fidelity or altruism or pride, or emotions such as love, embarrass...
You don't believe in Nature anymore. It's too isolated from you. You've abstracted it. It's so messy and damaged and sad. Your eyes glaze as you travel life's highway past all the crushed animals and the Big Gulp cups.
Our treatment of animals and our attitude toward them are crucial not only to any pretensions we have to ethical behavior but the humankind's intellectual and moral evolution. Which is how the human animal is meant to evolve, isn't it?