Quote: But I am not chicken, i am human, so my enjoyment of eating chickens, a result of my biological and sociological evolutionary history, is special to me..
Animal-eating is a social practice which is deeply embedded into modern culture. Slavery, the oppression of women, and institutionalized racism also once had this status; however, few if any suppose that this status is what makes these practices morally right or wrong. Animal-eating (speciesism) is wrong for the same reason slavery is wrong: it requires the persistent exploitation, coercion, and degradation of innocent people with basic welfare interests. So the fact that a practice has the weight of tradition on its side and a prominent place in a given culture is morally irrelevant.