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Darwin's theory of evolution
It is in the Origin of Species (1859) that Darwin presents his theory in its fullest and most general form. He starts with a brief discussion of the world of breeders and of how they achieve change by resorting to artificial selection, picking the forms that they find most desirable. Darwin then presents his major mechanism of natural selection. This comes in a two-part argument, first to the struggle for existence and then to natural selection. At the beginning of the third chapter, making
Humans and the Origin
The Origin is not about humans. This is not because Darwin did not think his theory applied to humans. Indeed, let it be clearly understood that Darwin was absolutely and completely convinced from the beginning that we humans evolved and that natural selection is the key mechanism. Going around the world as a young man on HMS Beagle had convinced him that we humans are part of the animal world (Browne, 1995). The Beagle was carrying three people taken a year or two earlier from Tierra del
Man as machine
Let us turn now to Darwin's direct treatment of our species in his Descent of Man (1871). My suspicion is that, for all his commitment to human evolution, Darwin would have initially preferred not to get into the human question in print. Others were fighting over the issue, and Darwin's programme was to cover, in detailed books, each of the various parts of the Origin. To that end, he had produced his massive The Variation of Animals and Plants under Domestication (1868), but Darwin was dragged
Human evolution
Thus expectedly, like staying at the Holiday Inn, in many respects there are no surprises in the Descent. Darwin simply ploughs ahead and argues that we humans are like other animals and hence are the produce of evolution through selection. “It is notorious that man is constructed on the same general type or model with other mammals. All the bones in his skeleton can be compared with corresponding bones in a monkey, bat, or seal. So it is with his muscles, nerves, blood-vessels and internal
What about causes?
As man at the present day is liable, like every other animal, to multiform individual differences or slight variations, so no doubt were the early progenitors of man; the variations being then as now induced by the same general causes, and governed by the same general and complex laws. As all animals tend to multiply beyond their means of subsistence, so it must have been with the progenitors of man; and this will inevitably have led to a struggle for existence and to natural selection. (p. 154)
S*xu*l selection
Thus far, it is all plain sailing. Now let us look at some issues of interest in Darwin's discussion of human evolution. Start with the fact that the Descent of Man is a strangely ill-balanced book. Most of it is not about humans at all! It is mainly about S*xu*l selection, as is flagged by the full title: The Descent of Man and of Selection in Relation to S*x. S*xu*l selection is an idea that Darwin had right back in the early days after hitting on natural selection. It is the selection that
Group selection
The level at which natural selection operates is a topic that has been much debated in evolutionary circles in the past half-century. Is it always exclusively for the individual, or can it work for the group? Most biologists most of the time opt for the “selfish gene” perspective, to use another of Dawkins's felicitous metaphors. They believe that adaptations serve the individual. My eyes are for my benefit, not for yours, and your genitals are for your reproductive benefit, not for mine. But
Culture
Where did Darwin stand on culture? He certainly recognized its importance and in respect thought that it could have a life of its own. One very popular approach to culture today, especially favored by many so-called evolutionary epistemologists, sees culture as taking off with its own units of heredity (Dawkins, 1976 calls them “memes” to contrast them with genes) and as being involved in some kind of struggle for existence for the best kind to survive to future generations. About the
Social Darwinism
Richard Dawkins has said that it is through our culture that humans are able to transcend their genes and control their destinies. Does Darwin believe this? I suspect that, if challenged, he would agree, but I suspect that the agreement would be half-hearted. One thing that worried Darwin, as it worried many of his contemporaries and continues to worry people down to the present, is the way in which modern medicine seems to be protecting the biologically inferior. People who in the natural
Progress
As the last quotation makes very clear, Darwin was a great believer in progress, both cultural and biological (Ruse, 1996). He thought that humans were top of the pile, and for good measure, European humans were top of the human pile. Was he not being inconsistent here? Surely natural selection is a relativistic phenomenon where what is best or adapted is a matter of circumstances. Is black better than white? It depends. If the background is granite, then the predator will not spot you if you
Conclusion
My starting claim was that Charles Darwin has no special theory of human evolution. He has his general theory of evolution that he applied to humans. We have seen that he was pretty consistent and directed in this attempt. Although humans did call for some tweaking of his general thinking, overall he treated us much like other organisms. Even when he thought we are special (our elevated status particularly), he strove to show that this stemmed from general principles and did not require ad hoc
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