Darwin

Darwin, in The Descent of Man, volume 1, pp. 26-27:

It appears as if the posterior molar or wisdom-teeth were tending to become rudimentary in the more civilised races of man. These teeth are rather smaller than the other molars, as is likewise the case with the corresponding teeth in the chimpanzee and orang; and they have only two separate fangs. They do not cut through the gums till about the seventeenth year, and I am assured by dentists that they are much more liable to decay, and are earlier lost, than the other teeth. It is also remarkable that they are much more liable to vary both in structure and in the period of their development than the other teeth. In the Melanian races, on the other hand, the wisdom-teeth are usually furnished with three separate fangs, and are generally sound: they also differ from the other molars in size less than in the Caucasian races. Prof. Schaaffhausen accounts for this difference between the races by "the posterior dental portion of the jaw being always shortened" in those that are civilised, and this shortening may, I presume, be safely attributed to civilised men habitually feeding on soft, cooked food, and thus using their jaws less. I am informed by Mr. Brace that it is becoming quite a common practice in the United States to remove some of the molar teeth of children, as the jaw does not grow large enough for the perfect development of the normal number.

This "Mr. Brace" was Charles Loring Brace, great-grandfather of the anthropologist of the same name who became well-known for studying dental reduction.

Darwin, in The Expression of Emotion in Man and Animals, p. 222-223, referring to the muscles involved in furrowing the brow during a frown:

It is not surprising that the corrugators should have become much more developed in man than in the anthropoid apes; for they are brought into incessant action by him under various circumstances, and will have been strengthened and modified by the inherited effects of use.... When the eyes are closed as quickly and as forcibly as possible, to save them from being injured by a blow, the corrugators contract. With savages or other men whose heads are uncovered, the eyebrows are continually lowered and contracted to serve as a shade against a too strong light; and this is effected partly by the corrugators. This movement would have been more especially serviceable to man, as soon as his early progenitors held their heads erect.

Interesting because (a) it's one of his clearer references to use inheritance; (b) it's a clear statement of comparative evolutionary anatomy applied to behavior, and (c) it presaged Grover Krantz by 100 years.

Another review of the evolution exhibit at the University of Pennsylvania Museum of Archaeology and Anthropology, this time a long piece by Julia Klein in the Wall Street Journal.

A propos to my post earlier this week about reading science in English class, Olivia Judson devotes her weekly blog entry to the question, "Was Darwin a good science writer?" No surprise, she thinks he was, despite certain dense sections, of the Origin.

Judson describes the confessionals of professional biologists who never read the founding work of evolutionary biology. I'm less concerned: Much of the Origin is hard to read, and many biology students would be better served reading a modern exegesis. I would be more interested in seeing students read a good selection of excerpts of Darwin's other works, especially the Voyage of the Beagle, and I'd like to see letter exchanges included as examples of scientific and literary correspondence.

Don't get me wrong: Both the Origin and the Descent of Man (both freely available from Darwin Online) reward close reading. As do many other dense works, including Fisher's Genetical Theory and Lotka's Elements of Physical Biology. But they're college-level works, no doubt, and not everyone's cup of tea.