CHAPTER THIRTEEN The Basic Components of the Human Mind Were Solidified During the Pleistocene Epoch

The basic components of the human mind, i.e., evolved psychological mechanisms, were solidified during the Pleistocene Epoch. The Pleistocene is the time period between 1.8 million years ago and 10,000 years ago that included the environmental selection pressures (both internal and external) that are responsible for the evolution of human psychological mechanisms. Although we share some psychological mechanisms with our pre-hominid ancestors—such as those that motivate predator avoidance behaviors—these mechanisms could not have “solidified ” before the arrival of our hominid ancestors. Humans continue to be subject to natural selection. However, because the time between the end of the Pleistocene and today is such a small portion of human existence (one half of 1%), it is unlikely that evolution has altered human design greatly over the last 10,000 years.