We Aren’t Unique: How Other Human Species Shaped Modern Human DNA (New Scientist Documentary)

We aren’t unique.  Once upon a time a number of different human species existed – not all at the same time but over the course of hundreds of thousands of years.  And, it seems, we got more than a little “Discovery Channel” with a lot of them.  So much so, that it has been established that a maximum of 7% of our DNA originated in our species, Homo Sapiens.  The rest came from other human species, the Neanderthals, Denisovans and some yet-to-be identified species who are still referred to as “ghost populations” as we haven’t yet discovered any remains.

This short documentary by New Scientist is presented by Ella al-Shamahi, who comes across as approachably clever, although I would never want to be playing against her in a game of chess.  Here she delves into the discoveries that rewrote human evolution in a clear and understandable way (you could call this Denisovans for Dummies if you wanted to get alliterative).  The documentary also covers not only why mating with already established human populations may have seemed like a good idea at the time to our ancestors, but the hidden cost of doing so.  It asks (and answers) questions about human origin that I may not have known I particularly wanted or needed to understand, but which are fascinating regardless.

Neanderthal Rationale – DNA of Primitive Species found in Homo Sapiens

 Image Credit Flickr User erix!

It will be of no surprise to anyone who has experienced Bristol on a Saturday night when the pubs close to discover that the DNA of the Neanderthal has been found in modern humans.

A study just published in the journal Science has shown that quite probably there was what is known as a ‘gene flow’ from Neanderthals to modern humans.

‘Gene flow’ is a polite scientific term for the very likely fact that Neanderthals got jiggy with our distant ancestors.  Although we lived in close proximity for thousands of years to what would have been our nearest relatives if they hadn’t become extinct scientist have till now dismissed the possibility of interbreeding between the two species.

However, meticulous research in to the DNA of the Neanderthal from bones has revealed a surprising result.  When the Neanderthal genome was compared to that of modern humans (all non-Africans – and that is an important point) Neanderthal code was discovered in each and every one of them, albeit tiny sequences.

Why is the non-African part important?  No trace of the genome has been found in people of African descent meaning that the fait was accompli after humans had migrated from Africa.

University of California scientists now believe that the act of union between the two species probably happened in the Middle East somewhere.

Work on mitochondrial DNA points towards the idea that the interbreeding was between Neanderthal men and human women – there is no proof of genetic flow in the opposite direction.

This likely indicates that the resulting offspring were probably brought up within human communities.

We bet they were terribly bullied at school.

Image Credits

Neanderthal Child - Wikimedia

Black and White Neanderthal - Wikimedia