“Chimps from one group began attacking and killing those from the other group and that turned into an escalated period of lethal violence,” study author Aaron Sandel, an anthropologist at the University of Texas at Austin, told Livescience... A very unusual story.
Hold on I saw this movie...
Battle for the Planet of the Apes.
I watched a documentary on HBO about chimpanzees doing this exact thing. Not new by any means. Good try UT but sol.
Is it any different than Human in a civil war?