Lamenting your lack of a spineless penis? Blame monogamy.
A new study has found that while our evolutionary predecessors may have basked in the glory of spiked man bits—known in the scientific world as penile spines—today’s men lack the necessary DNA to form them.
According to researchers, humans share the androgen receptor necessary to produce keratin structures with species like monkeys and mice. However, somewhere along the evolutionary march, the DNA needed to activate that receptor wandered off into the wilderness, never to be heard from again.
So what was the evolutionary advantage to losing our species’ rougher, tougher genitals? Here’s lead researcher Cory McLean’s hypothesis:
Some experiments have showed correlation between spines and promiscuity of species: species that are more monogamous, like humans, don’t have spines. Some experiments have showed correlation between spines and promiscuity of species: species that are more monogamous, like humans, don’t have spines.
In short, we potentially lost the spines so sex could last longer, hence creating a stronger emotional bond between couples. McLean is quick to note that correlation doesn’t mean causation but it’s an interesting thought that the human race could have been crafted for monogamy.
In any case, women around the world should thank their evolutionary stars for the change. According to the BBC, penile spines would have been a painful addition to sex:
[Penile spines] might play a part in inducing female ovulation in a small number of species, but there is evidence that they can cause damage to the female too. Then there is the suggestion that they might have evolved to remove “mating plugs”—material that some male species deposit in the female genital tract to block other males’ attempts to fertilize the same female.
Species have found plenty of creative ways to ensure that the best male’s DNA gets passed on to the next generation. Take for instance, the strategy of the Muscovy duck. Spiny penises have got nothing on this, uh, ballistic adaptation (NSFW).