Clothes are all the rage. We spend billions on designer bags and jackets, and our need for clothing is so unquenchable that the fashion industry is one of the least sustainable in the world, emitting more CO2 than aviation and shipping combined — as well as a myriad other environmental problems.

But humans haven’t always worn clothes. Chimps and bonobos, to whom we are almost 99 % related, are not known as fashionistas, and it’s doubtful that the first humans on the African savanna wore any kind of clothing at all. Just like any other trait we don’t share with our closest relatives, we needed to evolve the behaviour ourselves.

So when did this weird behaviour of dressing up first occur — and why?

Looking for old clothes doesn’t solve the problem. After all, clothes decompose quickly, making it difficult to find anything that’s much older than a couple of hundred years old. In fact, the oldest known garment is a dress from Tarkhan, Egypt, dated to 3,482-3,103 BCE, making it (only!) 5,000 years old.

Yet we know humans have lived in frozen regions for millennia before that. Doing that without some kind of protective layer is quite unfeasable. Living in Denmark, I know what I’m talking about here.

Surprisingly, the answer lies in lice.

Two different species of lice live off humans, the head louse and the body louse. And the body louse is way younger than its ascending counterpart. In fact, it only appeared as a separate species 70,000 years ago. Since body lice only lives in clothing, this strongly suggests that their habitat — human clothes — would’ve evolved around the same time.

This is quite amazing when you think about it. Not only did the invention of clothing keep us warm on chill winter nights, it also paved the way for a whole new species! That’s quite a feat for uncivilized people.

Why we wear clothes is more complex. Keeping us warm, yes, but our thirst for new fashion collections and the incredible diversity of clothes around the world suggests something else is at play.

I can’t think of a better description than culture. Different pieces of clothing might’ve become important for ritual purposes, or some might’ve begun to find some clothes sexually attractive. It’s difficult to say, as our evidence for the first 60,000 years of clothes’ history is meagre at best.

But it’s evident that clothing isn’t going anywhere soon. We even clothe our pets. Hopefully, we can find a way to make our fashion industry more sustainable in the future. If not, clothes will not only have given rise to a new species. It might also have played a role in killing several. Including, ultimately, our own.

Cover image: Public domain.