Re: [math-fun] Five-fingered hands

Henry Baker:

There must be a steep marginal cost associated with having 1 more finger, so that evolution calls a halt to digit inflation.

Michael Coates, professor in the department of Organismal Biology and Anatomy at the University of Chicago, might have addressed this a few years ago by positing that, on a genetic level, "the mechanisms involved in patterning the tips of our limbs include those involved in our reproductive success". http://www.scientificamerican.com/article.cfm?id=why-do-most-species-have