Regarding the column “Why do your fingers and toes wrinkle in the bathtub?”.
Now researchers have apparently concluded that wrinkled fingers provides a survival advantage when trying to forage for items in wet areas:
Cecil’s column discusses one possible mechanism behind the wrinkling, but the article provides another:
Interesting premise, but Cecil’s article mentions a further wrinkling effect, that of the bottom of the foot swelling. This is painful and makes it difficult to walk. So where is the evolutionary advantage there? Is the evolutionary advantage of getting a bit damp greater than the disadvantage of getting a lot wet?
Yeah, Cecil’s article is definitely behind the current science. It was actually known for decades that fingers with nerve damage didn’t get wrinkly [cite: Pruney fingers grip better | Nature], but it was only recently that someone made the obvious conclusion that this implies pruning can’t be due purely to water absorption.
For Irishman, I understand Cecil’s article to imply that immersion foot syndrome only occurs after many days of near-constant immersion, which is something that presumably our ancestors tried to avoid most of the time. So maybe getting too wrinkled is a disadvantage, but if it happens only very rarely, the advantage of getting a better footing in somewhat common wet weather probably makes getting wrinkled a net advantage.