It's all because of a missing piece of DNA
(NEWSER) - Were it not for evolution, sex could be a pretty uncomfortable prospect. But fortunately for humans, the male penis evolved in one particularly nice way: it lost its spikes. Some animals, including chimps and mice, still have penises dotted with hard spines. But Stanford researchers have discovered one particular chunk of non-coding DNA that was lost, leading to the spine-free human penis. "Couples everywhere can be thankful that this particular piece of DNA was ditched," says a researcher. More»