How culture has affected natural selection in man
Culture is arguably unique to humans. It possibly arose from the need to manage larger groups of people that congregated near agricultural fields as Jared Diamond suggests in Guns, Germs and Steel1 although it may have originated in tribal or hunter-gatherer societies. It is strongly linked with religion which can viewed as a cement holding together larger population masses. Recent developments in its research suggests two perspectives of culture: an outcome of natural selection which considers humans part of “nature” and culture as a purely human construct which arose as a consequence of advanced emotional intelligence which natural selection (according to believers of this theory) cannot explain. In order to see the effects on natural selection, one has to take a neutral stance.
It is established that natural selection cannot be evaded2 and as an outcome of this culture can be viewed as a consequence of natural selection. In other words, culture, in the context of human evolution, was selected for since it subsidised the struggle for life for the group. Individuals have to forego some individual “rights” in order to support the group as a whole. These “rights” include privacy, a certain amount of aggression towards others in the groups – things such a revenge – and so on. This is in essence altruistic which is inherently a group selected trait. The development of fire, agriculture, medicine and later various technologies have indeed helped the human race jump forward in the evolutionary struggle. This is, however, at the level of the group (group here refers to human society).
One inevitably comes across workers who suggest that culture has influenced the natural of man and has in a certain sense of the word excluded humans from natural selection. This is possibly true at the level of the individual as a cripple would not be able to survive in the wild as opposed to a healthy individual. Similarly, individuals of advanced age now have higher life expectancy in contrast to those of animals or even pre-society humans since parents are taken care of by offspring. Various other societal precepts have affected how individuals are selected for today. But since group selection offers a better means to justify the situation today, it must be viewed in that perspective.
Now the question arises that evolution produces only advanced species that are best adapted to survive in the world and that since humans have the added ability to “think” and “analyse” the consequences of this “advance” might not be sustainable. This may be true albeit since evolution is merely the accumulation of adaptions, any form of foresight (that is required in the intelligent design of humans) in the adaptations of species that have been brought to existence by evolutionary mechanisms. Sustainability is merely a human construct whose proponent is culture. This hence further reinforces the hypothesis that culture and all of its corollaries are a consequence of natural selection.
It can thus be concluded that cultural evolution has only affected individual survival while at the group level, it is but a consequence of natural selection.