Bush monkeys.

Heh:

Now I understand Glenn Reynolds a bit better:

“If little children and primates show pretty much the same pattern you see in adults, it calls into question just how deliberate these rationalization processes are,” [psychologist, Matthew D. Lieberman of the University of California, Los Angeles] says. “We tend to think people have an explicit agenda to rewrite history to make themselves look right, but that’s an outsider’s perspective. This experiment shows that there isn’t always much conscious thought going on.”