The answer: nothing. But at the outset, we promised you that we were not going to challenge that bit of conventional wisdom that holds that although animals matter morally , they don’t matter morally as much as humans do. Our conventional wisdom holds that even if animals matter less, they matter some, and hurting or killing them requires a justification. Responding to the need for such a justification by saying that we are at the top of some non-existent chain is a way of saying that it’s okay to hurt and kill animals without any moral justification. And that’s just a way of saying that you don’t think that animals matter at all morally and that we can make them suffer and kill them just because we are able to do so. Actually, if you stop and think about it for a minute, you’ll see that our power and ability to exploit nonhuman animals gives us the responsibility to protect them from exploitation!
Francione, Gary; Charlton, Anna (2013-06-24). Eat Like You Care: An Examination of the Morality of Eating Animals (Kindle Locations 1249-1253). Exempla Press. Kindle Edition.