Dr. Chris Stringer & the Origin of our Species

 Let's start with a few "big questions" :

How do you define your position in this world and your journey in evolution, with respect to other primates? Who have been our nearest "cousins" in this long evolutionary journey of ours?

Who were the Neanderthals? Did they fight with the archaic sapiens, or did they marry and inter-breed? Was there ever a Neanderthal-Sapiens war? Are Neanderthal traits still alive among some of us, or have they completely disappeared?

These were some of the questions that I (and all of us at Speaking Archaeologically) were pondering about, the day we sat to listen to Dr. Chris Stringer. I held a copy of his book "The Origin of Our Species" firmly in my hand, going through all the scribbled pages and little notes tucked in between printed words. 

"Changing Landscape of Evolutionary History of Upper Palaeolithic Hominins": read the title of Dr. Stringer's lecture. Some of the initial questions that he laid out were these: who was the last common ancestor of the Neanderthals and sapiens and how long ago did he/she live; what evidence do we have for the existence of the Denisovans; what do we know about the set of "Out of Africa" events.

The sheer pleasure of sitting for Dr. Stringer's lecture was the absolutely recent body of research that he put before us and the sneak-peek that we were offered into the world of the most recent debates stirring the world of Palaeolithic Quaternary studies. 

So what were my takeaways from this very engaging lecture?
Although for quite some time, Homo heidelbergensis were thought to be the last common ancestors, based on mainly morphological evidence, recent fossil evidence from Gran Dolina site at Atapuerca and Hulu cave, Nanjing, dating back to almost 900 thousand years (the former identified as a Homo antecessor fossil), seemed to look more "modern" than the heidelbergensis did. Again, later Chinese fossils from Dali and Harbin seemed to confirm these associations.

What further seems to have held the key to an earlier split between modern and archaic humans is the fossil evidence of an early Neanderthal with DNA from Sima de los Hudson site, Atapuerca, dating back to almost 430 thousand years. All of this evidence, and much more to come, will hopefully reshape our understanding of the evolutionary split between archaic sapiens and our extinct cousins, the Neanderthals.

Coming to the Denisovans, this is still a bit of an enigma for archaeologists across the globe. A late Middle Pleistocene Denisovan mandible from the Tibetan Plateau, and fossil teeth evidence from Sima de los, show lesser if any Neanderthal affinities. Moreover, some other fossils from Dali, Harbin, Xujiayao and Penghu have been claimed to be "Denisovans" , though such claims have still to be confirmed. More startling are genomes of native peoples from New Guinea and Australia that show at least two inter-breeding events, both probably post-dating 60 thousand years. The first of these was probably a Neanderthal, the latter a Denisovan.

The other question of Out of Africa events compels us to look at a date as early as 60 thousand years, and such that already by 45 thousand years, the African inhabitants were already there in parts of Eastern Europe, and even earlier in Apidima cave site from Greece. The dates have even been pushed back to 100 thousand years now, and this might open new directions in our understanding of global migrations and population niches. It would be useful to note what Eleanor Sherri has to observe in this regard, that probably no single ancestral population in one single region of Africa ever migrated out, and that our ancestors were certainly diverse in form and culture.

To end this note without mentioning a word about the Neanderthal extinction would be a sin, especially since I have been personally intrigued at looking into this question from articles published in Phys.org. Some of these are tantalizing and sensational, to say the least!
Dr. Stringer proved once again to be very balanced and cautious in his approach. He suggested that a combination of different factors--some biological, some cultural and others environmental--were responsible for the ultimate extinction of the Neanderthals.

As Dr. Stringer's lecture came to an end and an engaging conversation ensued, I realized how significant the lessons learnt in that one hour would be for me, at least later in my life. I came to think about the impact that this changing landscape of research in Upper Palaeolithic hominin evolution would have in our future understanding of the hominin phylogeny and our place in the scheme of hominin evolution. That is all which will define the origin of our species.