What makes us different from all the other animals? Is it our swollen brains, our idle hands, or perhaps our limber thumbs? In 2011, a research team reviewed the quirks of human DNA and came across another oddly shaped appendage that makes us who we are: I mean, of course, man's smooth and spineless member. The penises of lots of mammals are endowed with "horny papillae," hardened bumps or spikes that sometimes look like rows of studs on a fancy condom. These papillae enhance sensation, or so it has been claimed, and shorten a mating male's delay to climax. Since humans lost their phallic bumps several million years ago, it could be that we evolved to take it slow. And it could also be the case that longer-lasting sex produced more intimate relationships.
Read more at Slate.
