This will be a very short post about a relevant subject: how the Out of Africa theory has been upset by the discoveries that have taken place over the past twenty years. I came across a podcast by Chris Stringer RETHINKING "OUT OF AFRICA", and I encourage you to read it.
Christopher B. Stringer (born 1947), is a British anthropologist who has always backed the Out of Africa (OOA) theory (as the source of modern humans). However, the genetic evidence of admixture between Neanderthals, Denisovans, archaics and even super archaics with humans has led him to reconsider his position. Stringer has come to admit that we are a complex mix of different hominins. He now supports a modified version of the OOA theory that contemplates interbreeding.
In the podcast, Stringer describes the original concept on which the OOA theory was built: a single, isolated group in Africa, evolved into modern humans, and spread across the globe replacing all other hominins without mixing with them. He recognizes that it was very simplistic. The presence of Neanderthal DNA in Eurasians, Oceanians and Amerindians hints at a first contact in Southwest Asia and not a gradual intermingling as modern humans trekked into Europe. Furthermore, the presence of Denisovan ancestry in Eastern and Southern Asia and Oceanians also shows that humans also met these mysterious hominins and intermingled with them.
Below are some quotes from this work with my comments.
On Neanderthal Introgression; how, when, and where
Stringer points out a remarkable fact: the uniformity of Neanderthal introgression in Eurasians. If we had met them in Europe, the Europeans would have more Neanderthal DNA than other groups, after all, Neanderthals lived in Europe, but the situation is different. Stringer says: "The extraordinary thing is the level of DNA is about the same in a modern European, a modern Chinese and a modern New Guinean. One possibility is that an interbreeding event happened early on in southwest Asia. As modern humans first emerged from Africa, they met some Neanderthals —maybe only 25 Neanderthals and 1,000 modern humans. That would be enough. And then that DNA gets carried with those modern humans as they spread out from that area and diversify."
This is the first time I have seen the admixture event quantified. It is rather small-scale, isn't it? But it sounds realistic. The location in SW Asia (the Levant) is also reasonable.
On Archaic admixture inside Africa
Just as in Eurasia, ancient hominins survived in Africa until recently and admixed with African humans. This is something that I have posted about several times : "...some African people have acquired [DNA], perhaps even from Homo heidelbergensis... In Africa itself, archaic humans could have lingered in parts of the continent as well. From some recent genetic analyses, there is evidence of an input of archaic DNA into some modern African populations as recently as 35,000 years ago. So even in Africa, the process was more complicated than we thought."
Regarding this point, I notice that it seems to be a taboo-like subject in academic circles. Do scholars consider it discriminatory to suggest archaics or super archaics had sex with modern humans in Africa? Why can we say this about Eurasians and Oceanians, exchanging body fluids with Denisovans and Neantherthals, but not about Africans? It is just pure wokeness.
On the Flores Island "Hobbit" the Homo floresiensis
This hominin is remarkable, it survived until very recently (17,000 years ago), it has a large brain in relation to its size, it crossed a deep sea barrier to reach Flores Island and thrived in its island ecosystem. Where did they come from? Are they Homo erectus that shrunk in size to survive on the island? Are they the outcome of an even earlier hominin? Stringer ponders:
"... The suggestion is now that this [hominin] might represent an even earlier stage of human evolution, one that's closer to Homo habilis or even to Australopithecus, creatures that lived two million years ago or more in Africa. Although we've got no evidence of it happening yet, the argument is that one of those more primitive forms got out of Africa more than two million years ago, somehow found its way over to southeast Asia, and survived in isolation on the island of Flores until 17,000 years ago, when it went extinct. That would be an even more extraordinary story than a Homo erectus getting there and dwarfing, that you've actually got a relic of an earlier stage of human evolution that got all the way over there."
Unsolved questions
Stringer also mentions that "We've got a whole unknown history" for the Flores Island hominins and also for the Denisovans. More on this subject in my next posts.
He suggests that the Homo erectus probably evolved in Europe, resulting in the Homo antecessor, in Spain. That the Homo heidelbergensis evolved into Neanderthals in Europe, and also into Denisovans and modern humans (Though he does not say where the H. heidelbergensis originated!).
He hints that H. heidelbergensis who also lived in Africa, survived there until recently, possibly admixing there with modern Africans: "Africa had an overlap of modern and archaic humans, with the possibility in a continent so large that there were other descendants of heidelbergensis living there alongside Homo sapiens. These populations could have exchanged DNA too, evidence of which might be found in the genomes of living Africans."
Stringer concludes (highlight is mine): "We end up with quite a complex story, with even some of this ancient DNA coming back into modern humans within Africa. So our evolutionary story is mostly, but not absolutely, a Recent African Origin."
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall ©
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