Quote Originally Posted by julius_caesar_the_first View Post
I believe we are geneticly programed NOT to be able to kill each other in order to protect the species from self-destruction. From what I understand animals in general don't kill members of their own species except rarely and accidentally. Since I believe evolutionism I believe humans have the same instincts as other animals. Most normal people would have a hard time killing another human in normal circumstances.
Loads of animals will kill their own species - for personal gain. E.G. Male lions will kill each other, and then kill all the rival's cubs so they can produce their own. Birds will kill eggs of rival birds.

Going to more simple animals, many amphibians view developing amphibians of the same species as a snack, ditto fish and their fry.