yes, factor in human nature but first understand what it is. there are 360 million vegetarians in India, for example. eating meat isn't coded in our DNA.
Actually it is in the DNA. The shape of our teeth are both for eating meat and vegetables. India is the only example I am aware of with a culture of vegetarianism. That begs the question, why? One possibility is religion.
Many human cultures include the concept of slavery, that doesn't mean it is morally acceptable.
Coded into our DNA doesn't mean it is morally acceptable.