It's in Genesis, at least for the Christians
God made all the animals, and introduced them to Adam for him to name. I think that's a big honkin' clue to us. Jesus says, "What you do to the least of them, you do to me", right before he ascended to Heaven. Another humongous clue in my book. If God created the earth and saw "That it was good" (also in Genesis), I think we should try to keep it in "good" shape. Have we got work to do!!!