If We All Shave Our Hair, Will Lice Go Extinct?

In theory, yes, since the lice that dwell in our hair are specifically adapted to this habitat and can’t survive in the fur of other animals. So if no one had any hair, the itchy critters would have nowhere to live. 

In practice, this would obviously be pretty difficult to achieve – not least because it would require us to remove more than just our head hair. After all, humans carry three different ectoparasites: head lice, body lice, and the humiliating pubic lice. 

As their names suggest, each of these gangs occupies a particular territory. Pubic lice, for instance, are in their element among the thick, bristly foliage of our nether regions, yet struggle to grip onto our slinky head hair.

A few studies have even suggested that crab infestations may be declining as pubic hair removal becomes trendier, which just goes to show what we can achieve when we work together. For example, a paper published in 2006 hinted at a possible lice-free future if Brazilian waxing becomes more widespread. 

Another study from 2014 found that pubic lice are now considerably more common in men than women, correlating with the rising popularity of female landscaping while men remain largely happy for their old fella to be left ungroomed. 

And while crotch clearing is nowhere near voguish enough for pubic lice to start worrying just yet, these findings do hint at what might happen if we could convince everyone on the planet to remove all of their head and body hair. Of course, we’d all have to do it simultaneously and probably maintain our hairlessness for a period of time just to make sure there are no nits or lice clinging on to anyone’s scalp, armpit, or groin.

To be safe, we’d also need to wash all the hats in the world and possibly all of our clothes, as these can harbor nits too. Pillow cases as well, if we’re really serious about this.

Assuming we get everyone to play ball, this plan could potentially rid the world of human lice, although as this experiment has never been attempted before, it’s impossible to say if it would really work. For instance, even if every last ectoparasite were annihilated, there’s still no telling how other species might fill the gap once all our hair grows back.

After all, we know that human head and body lice evolved from similar parasites on chimpanzees, while pubic lice came from gorillas – whose fur is nice and pube-like in texture. If a vacancy were to open up in our fuzzier regions, it’s possible that a new type of lice may emerge after crossing over from animals.

For now, then, we’re probably better off just not sharing hats and continuing to painstakingly comb our kids’ hair.