> What exactly makes humans worthy of moral concern but non-human animals not? Nothing, in the sense of "moral concern" that you are asking about. We have law

> What exactly makes humans worthy of moral concern but non-human animals not? Nothing, in the sense of "moral concern" that you are asking about. We have laws against killing humans (and stealing from them, and many other things) because it's practical. On the other hand, it's practical to kill animals, and would be impractical not to. That said, I absolutely care about humans and animals (some more than others, but all at least some).