Our species was born in Africa and from this continent it left to colonize the rest of the world. It is easy to come across a statement like this in any reading we do about our origins. So repeated that it has managed to establish itself almost as scientific evidence. However, this is just an assumption yet to be proven. In fact, a new theory has forcefully stirred up these long-stalled ideas and proposes a new hypothesis that could revolutionize paleoanthropology: Homo sapiens may not have originated in Africa, but in the Near East.
New ideas for a very old topic
As if that were not enough, the authors of the hypothesis are eminences in the matter. José María Bermúdez de Castro is co-director of Atapuerca, together with Juan Luis Arsuaga and Eudald Carbonell, who received the Prince of Asturias Award for Scientific and Technical Research in 1997 for their work on the Sierra de Burgos site. Together with María Martinón-Torres , director of the National Center for Research on Human Evolution (CENIEH), they have published an article in the journal “Quaternary International” that questions the most widespread idea about our evolutionary journey. According to Bermudez de Castro:
“We are going against the current paradigm that, by inertia, affirms that everything is in Africa. What we do in this article is move the basket and make colleagues reflect. In science, nothing is resolved, everything is dynamic and subject to the evidence there is.”
The common thing among his scientific colleagues is to think that our species and the last common ancestor of Homo sapiens and the Neanderthals had their origin in Africa, so that the entire prehistoric population of Eurasia would come from Africa. Instead, Bermúdez de Castro and Martinón-Torres have revised the Middle Pleistocene fossil record from Africa and Southwest Asia to:
“Reinforce the need to at least consider the possibility of a non-African origin for the sapiens lineage as a plausible hypothesis.”
Already in the 1990s, when the Homo antecessor species was discovered in Atapuerca, more than 800,000 years old, it was proposed as the common ancestor of Sapiens and Neanderthals. However, the place where the fossil appeared, the western corner of Europe, caused the proposal to be discarded because of how far it was from the epicenter of evolution. So since then we continue with an important question: where is the common ancestor of modern humans and Neanderthals?
The complex puzzle of evolution
“If we go back in time, we don’t find any evidence that tells us that the common ancestor is in Africa, but that is what most people propose, simply because we have always thought that everything comes from this continent. However, we and other colleagues believe that Eurasia also has a prominent role in evolution during the last two million years.”
The study authors suggest that the earliest representatives of Homo sapiens to date have been discovered in Africa, but this does not mean that the common ancestor also originated in Africa . In other words, our species could have had an ancestor that evolved outside of Africa, although it could later return to the African continent.
The difficulty that may entail understanding this idea stems from the erroneous knowledge that the general public tends to have on the matter . Evolution is not linear, nor is it a process that can be represented on a timeline with different stages of expansion further and further from its origin. These ideas and dimensions are elements that paleoanthropologists create to facilitate the study and understanding of our evolution. But if we had to graphically represent the process of evolution and expansion of our ancestors, possibly the most accurate would be an intricate and bizarre doodle.
What are we searching for?
Genetic evidence suggests that a last common ancestor of Neanderthals and Sapiens may have lived between 550,000 and 765,000 years ago . The morphology of this species, yet to be found, should be defined as a mosaic of archaic and modern features . And where can we find it? According to the study, an interesting region would be Southwest Asia, that is, the Near East and, specifically, the Levantine corridor . It is a region to be exploited in terms of excavations and paleoanthropological studies, but war conflicts and economic problems hinder scientific development in the area.
All in all, experts have taken the new hypothesis as an interesting idea to consider. Bermúdez de Castro is proud of the welcome by his colleagues, who also consider it appropriate to rethink a paradigm that has stagnated. The findings that are yet to come will confirm or deny the hypothesis , but new well-argued points of view are always pillars on which to support the construction of knowledge about our origins.
Bermúdez de Castro, JM and Martín-Torres, M. 2022. The origin of the Homo sapiens lineage: When and where?. Quaternary International. DOI: 10.1016/j.quaint.2022.08.001.
Pichel, J. 2022. Do we only come from Africa? Spanish paleontologists question the trajectory of our species. elconfidencial.com.