Sorry, ain't buying it.
Humans have an inborn fear of loud noises and a rooting instinct.
That's about it. I.e. hominid canines shrank in size in a short span of time. Since primate canines are used primarily on each other, a sudden decrease in their size would indicate intense selective pressure away from using violence to solve problems. Ultimately, humans aren't subject to their inborn tendencies if they don't want to be. Any rock concert should be enough evidence to indicate we can overcome our inborn fear of loud noises, for instance.