One caveat that applies to all domains of evolutionary psychology, but especially to the evolution of reproductive strategies, is the fact that evolved tendencies are produced over deep time. Tendencies that are common to mammals have been produced by selection pressures operating over hundreds of millions of years, primate tendencies date back 50 million years, and features that are unique to humans have arisen during the time period after our split with our common ancestors over 5 MYA. It follows that evolved human tendencies do not respond to abrupt changes that occur in periods of thousands of years, much less changes like birth control that date back less than a century. Of course, we as humans respond to changes in our society almost overnight, and social, political, economic, and cultural changes can sweep the nation at the speed of the Internet. This means that with respect to human mate choice, a mix of ancient and modern influences operate on both conscious and unconscious levels. Keep in mind that in this chapter we focus our discussion on evolved
tendencies that have operated throughout human history often below the radar of our conscious awareness.