We are not as frightened as our ancestors were. (At least most of us aren't.)
This RadioLab program is amazing! http://www.radiolab.org/story/It seems humans have actually domesticated ourselves.
As a result, we are less prone to the violence that accompanies fear in wild animals.
Brian Hare tells us the story of Dmitri Belyaev, a geneticist and clandestine Darwinian who lived in Stalinist Russia and studied the domestication of the silver fox. Through generations of selectively breeding a captive population, Belyaev noticed not only increased docility, but also unexpected physical changes. Why did these gentler foxes necessarily look different than their wild ancestors? Tecumseh Fitch has a hypothesis, something about trailblazing cells and embryonic development. And Richard Wrangham takes it a step further, suggesting us humans may have domesticated ourselves.