WHEN DID HUMANS FIRST START WEARING CLOTHES?

 Ever wondered what cool sciencey stuff they are teaching undergraduates at the University of Queensland?


 Every school day I will post my newly learned cool fact... Enjoy 

14/03/2013

GENETICS

WHEN DID HUMANS FIRST START WEARING CLOTHES?

Genetic research shows that anatomically modern humans (AMH) appeared around 200,000 years ago.. It is extremely likely that they out competed their more primitive hominid cousins in other climates due to a series of technological advances and complex behaviours.

One of which was the development of clothing.

Clothing allowed humans to live in colder climates as they were protected from cold related body stress. This meant that they could live higher latitudes. And it also meant that they could survive colder glaciation periods.

 So when did humans first start wearing clothes?

 

Archaeologists first started to answer this question from physical evidence. Firstly, they found eyed needles for clothes production. These needles, made of bone, first appeared around 40,000 years ago. But this signals the arrival of complex clothing, not the start of it. 

One archeologist wrote “it would be unlikely that complex needles and thread arouse simultaneously with clothing use”.

So they could say with certainty that we had clothes from this 40,000 year ago point. 

There is also physical evidence of hide scraping tools, but these are from over 780,000 years ago. 

Hides can be used for many different things, shelter construction, carrying bags. Not necessarily clothes

Despite these hide scrapping tools, it seems likely that modern humans outcompeted previous species of homonym because of our use of clothing. And AMH did not appear until around 200,000 years ago.

This confusing and conflicting information was all that was available to answer the question till within the last decade. Indeed it has been as recently as the last few years the puzzle has been put together by genetic evidence.

And this has come from an unlikely source:

Parasites often provide an extremely valuable look into the genetic history of their hosts and humans are no different. 

Investigating from the genetic variation of the different types of lice that attack humans we can deduce some amazing things. 

Firstly, we can look at the divergence of genetic history between head lice and pubic lice. From genetic research done earlier in the previous decade,  we can see that head lice diverged genetically from pubic lice between 1.2 Million Years ago and 3 Million Years ago.

So we can deduce, that it was during this time that homonyms started to lose their body hair. 

The head louse is now a very different species from the Pubic dwelling cousin. 

As hair coverage on homonyms reduced to the very top of the head, the head louse became more and more specialised for living on in our hair.

However, the clothing louse diverged genetically from the head louse only very recently. 

Due to the nature of human development it is extremely unlikely that a divergence from its lineage would have been caused by anything other than the presence of clothing as a biological niche for the louse to fill. As Toups, Kitchen, Light & Reed,( 2011) put it “… determining when head and clothing lice began to diverge provides a date by which clothing must have been in regular use by humans.”

Basically scientists have taken elements from the head louse DNA and elements from the clothing lice DNA and analysed its genes sequences. They were looking for these Genes  

-              COI

-              18s RDNA

-              EF – 1(alpha)

-              RPII

Basically they took these genes from the lice and compared them to see the differences. The result of this genetic research was consistent with known human development. 

For example, (interestingly) the results showed that all head lice seem to have come from a population size of around 0.934X10+6, which is a considerable bottleneck for these tiny little insects. In other words we were that close to eliminating them. 

This would have been the result of body hair loss to the top of the head, not active human attempts. Post bottleneck stage shows, that a significant proportion of this small population becomes part of the divergence into clothing lice. 

This is perhaps a representation of how quickly the lice filled the new niche. Now for the part I’m sure you have all been waiting for.

Using this new latest study, when did humans start wearing clothes?

Well, as you can see from this graph there are the major events in human development, estimated time of body hair loss, first evidence of hide scrapers, first evidence of tailored clothing (the bone needle) etc.

The grey line shows the likelihood that the lice had genetically diverged into a new population. 

From the collective research of the genetics the median head louse clothing divergence is at  170,000 years ago.

 And the red area is the presence of a glaciation period where mean world temperature would have dropped.

This is all consistent evidence that supports the statement.

So...

 

Thanks to genetic research of parasites we are able to state that it is most likely that humans were wearing clothing around 170,000 years ago.