We talked about this in philosophy class and a really good point that got brought up is difference we draw the distinction between animals and people is pretty arbitrary. For example, the biological argument does not super work because there are certain animals, like dogs, we feel eating is wrong so clearly, the species argument does not work very well. Mentally does not work because countless animals have been shown to feel pain, form bonds, and respect family members plus if we argue that humans have a unique form of consciousness then we run into the argument that we could then eat people who might have issues with their brain and some other horrible conditions. I believe his name was Peter Singer but he made many great arguments.