Mechanisms and Mischaracterizations of Natural Selection

Natural selection is the primary mechanism through which evolution and speciation occur. However, despite the centrality of natural selection in evolutionary thought, recent research indicates that this subject is often misunderstood, even within higher education (Gregory, 2009). Indeed, even prior to the landmark contributions of Charles Darwin, evolutionary thought has been misunderstood to an alarming degree (Tattersall, 2009). In that vein, this essay seeks to define natural selection, explain its mechanisms, and contrast this explanation with common misconceptions about evolution.

Darwin (1859) noted that, despite the popular opinion of his day, time is not enough to foment adaptation and speciation. Rather, competition between and within species and an environment to which organisms may adapt are the sine qua non of evolution. Factors such as climate change and competition for limited resources challenge individual species and their variegated members. Those organisms which are most well-suited for their environment survive and propagate their genes, while less-suitable organisms either reproduce at a far lower rate or go extinct altogether (Bell, 2008). Natural selection operates on a phenotypic level; whether an organism survives and reproduces is determined by the degree to which it is physically adapted to its environment. However…