Essay: Sexual Selection, Adaptation and the Human Brain
December 19th, 2011 by Robert DePaolo | Posted in Psychology | No Comments » | 254 views | 
by Robert DePaolo
Abstract
This article discusses human evolution in terms of cue and trait detection skills facilitated by expansion of the human brain. A comparison is drawn regarding the co-impact of natural and sexual selection. The latter is considered to have a more potent, yet culturally influenced, happenstance effect on human evolution.
While natural selection is typically presumed to be the main driver of organic evolution, one could argue that in the course of an organism’s phylogenic development, nature, which changes slowly and often in punctuated fashion, has less to do with organic change than the simple interactions between males and females. Darwin of course alluded to this phenomenon in his discussions on sexual selection (1871). On the other hand the concept of fitness, which provides a cornerstone of his theory is not necessarily part of the sexual selection process, particularly for humans whose sensory discrimination, language and cognitive-creative capabilities might or might not coincide with fitness in a completely natural context – indeed might in some instances reverse nature’s tendency toward optimal organism-environmental congruence.
Evolution is a tricky concept; once tautological and vague. In and of itself the word implies a change or mutation into some new form. Yet the formal definition of the word has to do largely with the capacity among organisms to reproduce, as suggested in the work of Eberhard, (1996). The ambiguity of the term has to do with the fact that while adaptation and fitness are oft-used criteria, they are not encompassed in these narrow definitions. For example an organism can possess traits that are, or could be adaptive vis a vis the natural environment but unless he or she passed their genes on to the next generation, the potentially adaptive advantage of these traits would be irrelevant.