The Economist on Darwin

Next week we celebrate Darwin's 200th birthday, and everyone is getting into the act. This week's issue of The Economist, for example, includes a long piece on evolutionary biology and its influence.

The idea of evolution by natural selection is not hard to grasp. It just requires connecting some uncontentious propositions. These are that organisms vary from one another, even within a species, and that new variation can arise from time to time; that some of this variation is passed from parent to offspring; and that more individuals are born than can exist in the available space (or be sustained by the available resources). The consequence is what Darwin described in his book as a "struggle for existence". The weakest are eliminated in this struggle. The fit survive. The survivors pass on their traits to their offspring. Over enough time, this differential transmission of characters will lead to the formation of a new species.

That last bit isn't quite right. Species may arise through other processes. But if we made that last sentence read, "Over time, this differential transmission of characters will lead to new adaptations," we'd have a good account of the theory of evolution by natural selection. It's nice to see such a clear exposition of the theory in a mainstream newsmagazine. It's also nice to see this:

[M]any aspects of modern science could not work without accepting evolution. Darwin's ideas touch every corner of biology and medicine. They have also had an impact farther afield, in areas from art to politics. And their impact has been practical as well as theoretical. Both software engineers and drug developers, for example, often make use of evolutionary thinking when designing their products.

Evolutionary biology is a cornerstone of modern biology. It's not an optional bit that can be discarded if it seems inconvenient. The evidence for evolution is inextricably wound up with the evidence for genetics, development, physiology, anatomy, geology, physics, and chemistry. It is part and parcel of a scientific understanding of the natural world.