The Fitzwilliam Museum, Cambridge UK, is putting on an exhibition titled, "Endless Forms: Darwin, Natural Science and the Visual Arts."
The exhibition is accompanied by a well-produced webiste, which includes descriptions of the collection, some material for educators (including visit information for the UK), and a virtual exhibition. Some of the text may be stretching Darwin's direct influence on the arts -- a naturalistic eye goes back farther than Audubon, for example, but several sections are interesting. Here's an excerpt from "Darwin and the Impressionists":
Edgar Degas, too, is known to have engaged directly with Darwinian theory, especially through reading Expression of the Emotions in Man and Animals soon after it was published in French in 1874. His images of dancers, singers, and criminals in the decades that followed stressed a kinship with animals in their features and gestures, and hinted at the possibility of human degeneration to an animal condition.
I think it's an open question how much Darwinism really affected popular culture. Several of the artists represented (e.g., Robert Farren) were already representing ancient creatures well before the publication of the Origin. Artists seem to have reacted to a greater understanding of nature, and science drew on that art as well as upon itself.
(via Jeff Hayes)
UPDATE (2009/06/23): I should mention that the BBC has a slideshow based on the exhibition. It doesn't have as much material, but it does have nice big versions of some of the included artwork. Plus, kinda depressing classical music.