Denisovan may have split from Homo erectus

A recent research article (not peer-reviewed) published in BioRxiv (Scalable ARG-free Detection of Denisovan-mediated Superarchaic Introgression Reveals Heterogeneous Patterns across Populations. Noel McAllister, Sebastian Zöllner, Xinjun Zhang, bioRxiv 2026.06.25.734355; doi: https://doi.org/10.64898/2026.06.25.734355), used simulations based on a specific computing program to explore the sites in our genomes where superarchaic introgression may be found. Introgression that reached us via Denisovans.

It looks into the genome of modern populations and finds that HLA/MHC loci have higher introgression scores than other sites. This, according to the authors, "...is consistent with previous evidence that immune-related loci retain archaic variants. At the same time, HLA/MHC is among the most polymorphic regions of the human genome and has been shaped by pathogen-mediated and balancing selection, both of which can preserve deeply divergent haplotypes and generate unusually deep local genealogies..." However, they caution that these high scores may not only be due to archaic introgression: " ...HLA/MHC is also one of the clearest examples of long-term balancing selection, which also preserves deeply diverged haplotypes without recent introgression... We therefore interpret the HLA/MHC signal cautiously. It should not be treated as definitive evidence for superarchaic ancestry by itself. Nonetheless, its repeated elevation across all three populations is notable and suggests that immune-related regions may be especially informative targets for future local haplotype, ARG-based, and functional analyses."

It makes sense that alleles linked to immunity, received from superarchaics, if they provide a benefit, will be preserved across generations.

The paper then discusses Denisovans and mentions an interesting fact, that Denisovans could have evolved from Homo erectus: "Our results also intersect with the recent paleoproteomic evidence suggesting that some Denisovan superarchaic ancestry may ultimately derive from populations related to H. erectus."

It also notes that population structure can be mistaken for introgression: "A further limitation is that deep population structure and introgression remain intrinsically difficult to separate. Structured ancestral populations can generate old coalescent times and divergent haplotypes, and some recent models have shown that deep structure may explain signals previously interpreted as archaic or ghost admixture."

It presents a scenario that I had not read about before: "Hominin evolution may have involved both long-lived structured populations and episodic admixture among deeply diverged groups." Which is very plausible, we can imagine, especially in Africa this scenario, with archaic populations and ancestral modern humans living in isolated, deeply structured populations admixing sporadically, and adding diversity to the Homo sapiens group.

The other branches of the human tree also followed that pattern, with Neanderthals in western Eurasia and Denisovans in the Eastern part of Asia. Mixing with modern humans as our ancestors met them.

Homo erectus has been shown to have admixed with Denisovans (see this post), but, this article suggests that Denisovans evolved from Homo erectus, which is a very reasonable assumption. I recently posted about Denisovans and Homo heidelbergensis being related (also Neanderthals), it is possible that the common ancestor for these groups evolved from erectus (via Homo antecessor) in Eurasia.

Evidence seems to be building a stronger case for an Eurasian origin for hominins.

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall © 

Homo heidelbergensis from Africa and Denisovans are linked

A research paper published in 2025 (Candidate Denisovan fossils identified through gene regulatory phenotyping, by Nadav Mishol, Gadi Herzlinger, Yoel Rak, Uzy Smilanksy, Liran Carmel, David Gokhman, bioRxiv 2024.04.18.590145; doi: https://doi.org/10.1101/2024.04.18.590145 and in Proceedings of the National Academy of Sciences doi: 10.1073/pnas.2513968122) reported the study of the shape of different skulls from the Middle Pleistocene, spanning Eurasian and African specimens, including Neanderthal, Homo erectus and modern humans to try to identify the traits that indicate the Denisovan morphology. The study found something quite interesting besides the similarity between Denisovans and some East Asian fossils, below I cite their conclusions and highlight the relevant part:

"these analyses revealed that the East Asian specimens of Harbin and Dali show an exceptionally high concordance with the Denisovan profile, surpassing all other examined Middle Pleistocene hominin specimens, including Neanderthals. Specifically, 15 out of 18 of Dali’s features and 16 out of 18 of Harbin’s matched Denisovan predictions. These findings are robust to overall skull size and to correlations between phenotypes. We also found that Kabwe 1 shows a strong affinity to the Denisovan–Neanderthal clade and might be placed near its root"

Kabwe the African fossil

Kabwe 1 was unearthed in 1921 in Kabwe, in what is now Zambia. It is a fossil skull also known as the Rhodesia man or Broken Hill, and has been classified as a member of the Homo heidelbergensis group. It is rather primitive, with heavy brow ridges, and a flat forehead, its shape resembles that of Homo erectus yet it is relatively recent, dated to around 324,000 - 274,000 years old (source) which makes it contemporaneous with the first members of our species, Homo sapiens who are said to have appeared in North Africa 300,000 years ago.

Besides the oddity of archaic and moderns co-existing in Africa 300 kya. Kabwe 1 is extremely close to Denisovans! Which is an unusual finding because Denisovans are not known to have migrated into Africa, they are better known as East or Southeast, or Central Asian populations that admixed over there with modern humans as these entered that region around 50 ky ago.

Let's see what the paper has to say about this similarity:

"Several test subjects, most notably Kabwe 1, exhibit unexpectedly high concordance with the Denisovan profile, despite being unlikely to be Denisovans. Although discovered in Africa, Kabwe 1 not only aligns well with the Denisovan profile (Fig. 4) but also clusters closely in the PCA with Dali, a potential Denisovan (Fig. 6 and SI Appendix, Fig. S3). Although our current knowledge of Denisovan habitat is lacking, it is unlikely that they reached Southern Africa. Hence, Kabwe 1 is unlikely to be directly positioned on the Denisovan lineage. A more plausible explanation is that the resemblance of some of these specimens to Denisovans reflects a proximal phylogenetic affinity with the Neanderthal–Denisovan clade, perhaps close to its root."

So, the authors assume that there has been no migration of Denisovans into Africa, and based on this assumption they suggest that the African fossil is similar to Denisovans because it was a close relative to the Denisovan-Neanderthal group that left Africa, and split into Neanderthals and Denisovans. A conclusion repeated again in the closing part of the paper, as you can read below:

"The resemblance of several specimens attributed to H. heidelbergensis to the Denisovan profile, and specifically the African specimen Kabwe 1, is particularly intriguing. The similarity between Kabwe 1 and other high-scoring specimens is evident in all PCAs (Figure 4 and Supplementary Figure 10), suggesting that this resemblance is not limited to Denisovan-like phenotypes. Despite our limited knowledge of the true range of Denisovans, it is unlikely that they reached Southern Africa, hence Kabwe 1 is unlikely to be directly positioned on the Denisovan lineage. A more plausible explanation is that the resemblance of some of these specimens to Denisovans reflects a proximal phylogenetic affinity with Denisovans. For example, H. heidelbergensis specimens were positioned either close to the split between modern and archaic humans or close to the split between Neanderthals and Denisovans [29]. If H. heidelbergensis is indeed phylogenetically closer to the Neanderthal-Denisovan split than Neanderthals are, it is expected to exhibit an even greater similarity to the Denisovan profile than Neanderthals do. Another alternative explanation is that Denisovans might have retained several ancestral phenotypes observed in H. heidelbergensis [59], or that these phenotypes were affected by gene flow into Denisovans, originating from contemporaneous H. heidelbergensis [17]."

The authors don't explain how the African fossil can be closer to the Denisovans than the Neanderthals. It is assumed that neither group entered Africa. That the common ancestor of Denisovans and Neanderthals left Africa, splitting from the group that would lead to us, modern humans. Then, in Eurasia, the ancestral group of Denisovans and Neanderthals split into two species, one heading East, the other colonizing the West of Eurasia. So, how could a primitive hominin in Zambia be closer to a group that split in the Levant?

The second explanation requires explaining why the Denisovans ended up with the primitive ancestral form found in Kabwe but not the Neanderthals. The final explanation of gene flow into Denisovans via contemporaneous Homo heidelbergensis would require them being alive and kicking in Western Eurasia around 600 ky ago!

The nice part of this paper is that it is thought provoking: Denisovans and Homo heidelbergensis are linked. Notice that Heidelbergensis got its name from a site in Heidelberg, Germany where it was found in 1908 (source). It is found in Europe and Africa. Of course, it is claimed to have evolved in Africa. But, could these people have evolved in Eurasia, leading to the ancestor of modern humans, Denisovans and Neanderthals, adding more genes to the Denisovans who carried them east, and finally, a group of heidelbergensis moved into Africa resulting in the Zambia fossils?

The current bias against an Into Africa flow makes this hypothesis unlikely to be accepted. But it seems the most logical one. Furthermore, flow of the heidelbergensis into Atapuerca people and then from Spain into North Africa seems a plausible explanation for the evolution of Modern Humans separately from the Neanderthal-Denisovan group.

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall © 

Homo antecessor the base of the human tree (in Spain)

Today's post will continue exploring the subject of yesterday's post, about the Eurasian origin of Homo sapiens, from a basal population that lived 900 to 700 thousand years ago in Atapuerca, Spain, the Homo antecessor, that originated Neanderthals, Denisovans, and our species, in Europe.

Martinón-Torres et al., 2019 analyzed the teet of the Atapuerca fossils, and concluded that Homo antecessor is the common ancestor of Neanderthals, Denisovans, and modern humans: (highlight is mine) "Overall, the data presented here support the taxonomic validity of Homo antecessor, since this species presents a unique mosaic of traits. Homo antecessor displays several primitive features for the genus Homo as well as some traits exclusively shared with Early and Middle Pleistocene Eurasian hominins. Some of these Eurasian traits were retained by the Middle Pleistocene hominins of Europe, and subsequently became the typical condition of the Neanderthal lineage. Although other skeletal parts present resemblances with Homo sapiens, TD6.2 teeth do not show any synapomorphy with modern humans. In addition, TD6.2 teeth can be well differentiated from those of Asian Homo erectus. The dental evidence is compatible with previous hypothesis about H. antecessor belonging to the basal population from which H. sapiens, Homo neanderthalensis, and Denisovans emerged."

This conclusion was ratified by Welker et al., 2020, who analyzed the proteins found in the teeth of the Atapuerca fossils, and compared them to the ones extracted from the Dmanisi, Georgia hominins (believed to be Homo erectus). See the full article for free here.

Weker's team says its findings "provide evidence that H. antecessor is a close sister lineage to subsequent Middle and Late Pleistocene hominins, including modern humans, Neanderthals and Denisovans. This placement implies that the modern-like face of H. antecessor —that is, similar to that of modern humans— may have a considerably deep ancestry in the genus Homo, and that the cranial morphology of Neanderthals represents a derived form."

Interestingly, Huguet, et al., 2025 published a paper in Nature about The earliest human face of Western Europe and assigned it to an Homo erectus. It was found in Spain in the Sierra de Atapuerca, at the Sima del Elefante site (TE7 level). This is 1.1 to 1.4 million years old, and predates the later Homo antecessor found in the same region.

The midface bones uncovered at Sima del Elefante "... are primitive for the Homo clade and they do not display the modern-like aspect exhibited by Homo antecessor found at the neighbouring Gran Dolina site... Furthermore, ATE7-1 is more derived in the nasoalveolar region than the Dmanisi and other roughly contemporaneous hominins" These differences between erectus in Spain and Georgia, with the former being less primitive (more derived), shows that erectus were evolving in Western Eurasia but had not yet acquired the modern appearance of the antecessor people.

A surprising fact is that the people living at Atapuerca one million years ago were cannibals according to Carbonell et al., 2010; it wasn't symbolic cannibalism, it had a nutritional purpose: " In conclusion, about 1 million years ago, the hominids of level TD6 added cannibalism to their set of survival strategies as a way of competing with other human groups for available resources. This practice, accepted and included in their social system, is the oldest example of cultural cannibalism known to date."

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall © 

The common ancestor of Denisovans, Neanderthals and Humans

A paper published in February of this year, in Nature, by Hublin et al., analyzed the shape of jaws and teeth of several fossils collected in Morocco and compared them to those of Neanderthals, the older Homo antecessor, modern humans, and Homo erectus to try to unravel how our Homo sapiens species evolved in North Africa, the site where the oldest human remains have been found (300,000 years old).

The paper mentions that the common ancestor of modern humans, Neanderthals, and Asian Denisovans lived between 765 and 550 thousand years ago (ka), but where it lived is still a mystery. Some studies have proposed that the Homo antecessor, whose remains were uncovered in the Gran Dolina site, Atapuerca, Spain (950-770 ka) is the candidate for this last common ancestor of the later homo genus.

The Homo antecessor fossils are named in the paper as TD6, after the layer where they were found. If antecessor is the ancestor, it means we had a European origin. However, all of the oldest Homo sapiens remains older than 90,000 years, have been found either in North Africa or in the Levant, taken by the proponents of the Out of Africa (OOA) theory as an indication of an African origin for modern humans, and Africa as the site of the last common ancestor of Denisovans, Neanderthals, and us.

This paper compares remains found in a site close to Casablanca, Morocco, in northwest Africa, known as the Grotte à Hominidés (which we name here as ThI-GH). These remains are in the right time period to be ancestral to all groups (773 ka).

The conclusions of Hublin et al., are quoted below, I have highlighted some relevant parts:

"In North Africa, the ThI-GH hominins are the only specimens unearthed within an indisputable stratigraphic context and securely dated to the MBT at a nominal age of 773 ±4 ka. These hominins cannot be directly compared with later specimens, such as the Kabwe or Bodo skulls, which have been tentatively assigned to H. heidelbergensis. Not only do these specimens differ substantially in age, but they also lack preservation of comparable anatomical parts. Our analysis suggests that the ThI-GH hominins probably belong to an evolved form of H. erectus sensu lato in North Africa, much as H. antecessor does in Europe. However, the ThI-GH hominins offer an interesting contrast to both the Spanish fossils and the considerably older fossils from Tighennif (Algeria), which are likely to date to at least 1,000 ka. The fossil mandibles from Tighennif appear more primitive, larger and more robust than both the European H. antecessor and the northwest African ThI-GH fossils. The Spanish and Moroccan fossils share several features in their teeth and mandibles. Both groups display a combination of archaic and derived features reminiscent of later hominins (Supplementary Table 25). These similarities revive the question of possible exchanges across the Strait of Gibraltar during the EP. Nevertheless, the ThI-GH hominins are different from the TD6 hominins. The pattern of these differences suggests that regional differentiation between Europe and North Africa was already present by the late EP. Apparent Neanderthal-like features on the larger ThI-GH-1 mandible could reflect primitive retentions, allometric effects or convergent evolution but, when more phylogenetically informative dental characters are considered, the Spanish specimens appear more derived towards the Neanderthal morphology that later emerged in western Eurasia.
The origin of H. sapiens, and the precise timing of the divergence of its ancestral populations from the Neanderthal–Denisovan clade, remain subjects of debate. Anatomical evidence has at times been used to argue for a split predating 800 ka and even for an alternative Asian ancestry of our species. In this context, the Maghreb fossils are key to understanding the diversification of MP hominins. The morphology of the ThI-GH hominins places them close to the split between the African and Eurasian lineages. Our findings not only align with the phylogenetic structure inferred from palaeogenetic data but also highlight the Maghreb as a pivotal region for understanding the emergence of our species, reinforcing the case for an African rather than a Eurasian ancestry of H. sapiens."

Comments

The closing phrase about an African origin of modern humans is expected as the authors don't want to go against the established dogma. However, the point about intercontinental exchange via Gibraltar during the Early Pleistocene is extremely interesting. It is very likely that our common ancestor, even H. erectus had the ability to cross such a narrow body of water in boats. The similarity of Atapuerca specimens with Neanderthals is also relevant, as Neanderthals are Eurasian, not African. The differences between H. heidelbergensis specimens within Africa and the Moroccan fossils hints at a separate stem of hominins in North Africa vs. central and southern Africa. Furthermore, the authors suggest that it was Homo erectuswho evolved into the Moroccan specimens, and that the erectus present in Africa were more primitive and robust than the European lineage.

Taken together, this suggests, in my opinion, That the erectus line, after evolving in Eurasia, moved into Northern Africa via Gibraltar, and had already settled in Western Europe, and evolved in this region (Spain-Morocco) into the common ancestor of Neanderthals-Denisovans and Humans, in Europe.

How can we account for the absence of Denisovans and Neanderthals in Africa? But, assume that modern humans originated there? This is a serious flaw in the African origin theory.

An answer to those questions is that the "common ancestor" migrated east into Eurasia and the Levant, diverging there into Neanderthals and Denisovans who, respectively, colonized Western and Eastern Eurasia. From this common root, modern humans split, entering Africa via Sinai or maybe Bab el Mandeb, while spreading eastwards across Eurasia.

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall © 

Much Older divergence dates for Denisovans, Humans, and Neanderthals: Implications

I have already posted about this, reporting it last October: The dates for the splits between the different archaic groups has revised in a paper published in Science last September. Research by Xiabo Feng et al., 2025 suggests that a skull unearthed in China known as Yunxian 2 belongs to an Asian group of hominins known as Homo longi, which encompasses the Denisovans (the clade's name is relatively new and was created to formalize the diverse remains from the Middle Pleistocene of East Asia, including Denisovans). It places the split between humans and Denisovans at 1.32 million years ago (Ma) and proposes that Neanderthals split even earlier: 1.38 Ma. The Homo sapiens are much older than previously assumed: 1.02 Ma.

This is the article: Xiaobo Feng et al., The phylogenetic position of the Yunxian cranium elucidates the origin of Homo longi and the Denisovans. Science 389, 1320-1324 (2025). DOI:10.1126/science.ado9202.

Today's post will look into the implications of these earlier dates for our lineage.

A very early split with a different sequence to it

The accepted view is that the ancestor of modern humans and the group leading to Neanderthals and Denisovans split first, and then, Neanderthals and Denisovans separated into two different groups in Eurasia, Neanderthals heading west, into Europe and the Caucasus while Denisovans headed east into Siberia, Tibet, Southern, Southeastern and Eastern Asia. This paper upends that notion. The Neanderthals split first, then humans and Denisovans (called Longi clade in this article) split.

The authors, considering the very old age of Yunxian2 (~1 million years old) push the roots of Human-Neanderthal/Denisovan split further back ("deeper"): "Both the H. sapiens and H. longi clades have deep roots extending beyond the Middle Pleistocene and probably experienced rapid early diversification." The current dates for the Human - Neandersovan split is around 500,000 to 700,000 years ago, this paper suggests it is older: ".The origin of the longi clade can be inferred to be about 1.2 Ma, slightly older than the Yunxian fossils. The origin of the sapiens clade is estimated to be about 1.02 Ma, also close to the age of Yunxian. The divergence between the longi clade and the sapiens clade is at about 1.32 Ma. The monophyletic Neanderthal clade, widely thought to be sister to H. sapiens, diverged from the longi and sapiens clades at about 1.38 Ma in our analysis."

The paper includes the following dated phylogenetic tree (click here for full size image or click on the image below to enlarge it):

Fig. 4. Phylogeny and divergence time of the 57 selected fossil operational taxonomic units from the genus Homo.
The topology of the tree was the majority consensus of the most parsimonious trees from the parsimony analysis in TNT (34). The divergence time was inferred from the Bayesian tip-dating analysis in MrBayes 3.2 (35). Branch lengths are proportional to the division age in thousands of years (Ka). Numbers at the internal nodes are the median ages, and the blue bars indicate the 95% highest posterior density interval of the node ages. The red half-brackets on the right indicate the ranges of the Neanderthal, longi, and sapiens clades. The numbers in red highlight the ages of division of the three clades. Yunxian is also highlighted in red. Xiabo Feng et al., 2025

The shape of the skull is interpreted by this paper as having a "mosaic morphology, which retains plesiomorphies seen in H. erectus/H. ergaster, Kabwe, and Petralona while developing apomorphies shared with H. longi and H. sapiens" Indeed, Homo erectus present in Eurasia since ~2 million years ago is surely linked to the root of the Denisovan (Longi) clade.

Implications

Neanderthal Dispersal

By having Neanderthal split first, 1.38 Ma, we can imagine the pre-longi/sapiens group remaining in Africa and the Neanderthals heading out of Africa into Eurasia. This clade includes the Sima de los Huesos (SH in the phylogenetic tree, above) specimen, which is old, and linked to Neanderthals, and places it as an early split of that clade. Mainstream Neanderthals appear 781 to 600 kya.

Adopting a position embraced by Chinese scholars (and government), they move Neanderthals further away from modern humans, and place Denisovans (H. longi) closer to us; after all, Neanderthals are Western Eurasians, and Longi are East Asian (Chinese!).

See Qiang Ji, 2021 version for Western consumption, and the Chinese version in The Innovation, Qiang Ji et al., 2021 from which the following image was taken, showing the Neanderthals displaced by Longi as our sister clade:

Graphical abstract . Qiang Ji et al., 2021

However Qiang Ji et al., (2021) in their detailed phylogenetic, dated tree (Fig. 4), give later dates than >Xiabo Feng et al., 2025: ~1 Ma for the Neanderthal split, 949 kya for the Denisovan-Human split, and 770 ky for the root of H. sapiens. See below, highlight is mine. Note: OTU = operational taxonomic unit, a name used for genetically similar creatures, analog to a species definition.

" Harbin cranium and H. sapiens shared a common ancestor at ∼949 ka (1,041.41–875.25 ka). The Neanderthal-H. sapiens divergence time in our analysis was ∼1,007 ka (1,114–919 ka). This estimation falls in the range based on mtDNAs for the split between the basal Neanderthal (Sima de los Huesos) and the H. sapiens lineage, but is much older than the estimation based on nuclear DNAs for the splits between the Neanderthal and H. sapiens lineages. However, it is possible that this younger estimated divergence date is an artifact of statistical averaging between “super-archaic” and “recent gene flow” events. The common ancestor of the H. sapiens OTUs included in our analysis is as old as ∼770 ka (922–622 ka), suggesting that the H. sapiens clade has a much deeper origin time than previously estimated. The Eurasian H. sapiens OTUs share a common ancestor ∼416 ka (534–305 ka) old. Outside of Africa, however, the earliest known H. sapiens fossil is only ∼210 ka."

Qiang Ji et al., 2021 suggest that "Sympatric isolation of small populations combined with stochastic long-distance dispersals is the best fitting biogeographical model for interpreting the evolution of the Homo genus...multi-lineages of Homo coexisted in Africa, Europe, and Asia during the Middle and Late Pleistocene. These Homo lineages probably had a strong capability of dispersing for long distances, but remained in relatively small and isolated populations." Sympatric isolation means that even though they shared the same overlapping territory, they evolved separately, not because of physical barriers, but by other ones (genetic, environmental, adaptative, reproductive, specializations), that keep them apart.

What would keep Neanderthals, who during the later period 120-50 kya spanned Western Eurasia from Altai to Portugal, from moving on into America. They could have skirted the Denisovans (who seem to be more adapted to temperate and tropical climates) by living in colder, glacial spots, in Europe and Asia. They could have gone across West-Central Siberia, Northern Siberia and Northeastern Siberia to Bering, and into America. Nobody digs deep enough to find remains 1.3 million years old!. I am not joking, sediments deposit at a rate of 0.10 to 0.12 mm/year (Source) that is 14 times smaller than 1/16th of an inch. Over one million years it represents 120 m of sediment (393 feet). Archaeologists have only scraped the surface (of course, when digging in areas scoured by previous erosion, or by river banks, other elements factor in, recucing sediment buildup.

Neanderthals, well adapted to ice-cold climates, could have easily reached America 1.38 Ma.

Denisovans

The phylo tree built by Xiabo Feng et al., 2025, follows the line set by Qiang Ji. It has older dates, and places the Homo Antecessor at the base of the Denisovan tree, H. antecessor is a Western European specimen, discovered in Atapuerca, Spain. This suggests a very wide territory for Denisovans.

Although their presence has been described in the temperate and tropical parts of Asia, like the Philippines, Sunda, Southern and Southeastern Asia, they also lived in Tibet, and overlapped Neanderthals in Denisova Cave, Altai, Russia, further north, in colder climes, ~200 kya. The Harbin individual, ~146 kya lived in Northeastern China which even nowadays is cold. Xijung Ni et al., 2021, state, regarding the Harbin remains that "the northerly location of the Harbin site also has implications for Middle Pleistocene human adaptive capabilities, since, even in the present interglacial, this region has winter temperatures averaging more than 16°C below zero [3.2°F] The very large size of the Harbin individual (as judged from the size of the cranium) may indicate physical adaptation to such conditions."

This suggests that they too could have moved northeast towards Beringia. Did they reach America 1.32 Ma?

Humans

Homo sapiens is pushed back 700,000 years, from the commonly accepted date of 300 kya to one million years ago. In Africa, alone, isolated from the Denisovans and Neanderthals who left them for Eurasia.

The Gap in the fossil record

The oldest members of the human branches are the Irhoud, the 300 ky old human from Morocco, the Tabun 2 person from Israel, and Florisbad a H. Heidelbergensis from South Africa. But there is a gap of 700,000 years between them and the split date with Denisovans!

Xijung Ni et al., 2021 who proposed an older than the commonly accepted date for the split "(∼416 ka (534–305 ka) old", yet much shorter than the 1 million years proposed by Xiabo Feng et al., 2025, wonder why there is such a gap between the first fossils and the split date. The team favors an African origin for Homo sapiens offers the following explanation:

"There is a large time gap between the hypothetical common ancestor of Eurasian H. sapiens and the actual fossil record, from the Bayesian tip-dating analysis. One plausible hypothesis is that the ancestral population of Eurasian H. sapiens may have diversified in Africa for many millennia before they dispersed into Eurasia. Genetic studies on ancient DNA suggest that the initial genetic exchanges between Neanderthals and H. sapiens occurred between 468 and 219 ka, or between ∼370 and 100 ka, and the introgression may have originated through gene flow from an African source. Interestingly, not only does the estimated time of the introgression event between Neanderthals and H. sapiens roughly overlap our prediction for the age of the common ancestor of Eurasian H. sapiens, but the African origin of the introgression is also consistent with our African ancestral population hypothesis."

Perhaps the fossil record is incomplete because we haven't found the specimens. Humans are intelligent so they were not easy prey or caught in quicksand, they were surely buried. So, unless we dig deep enough in the right places and find burials, we won't find them.

I believe that there was "diversification" within Africa as ancient archaics that indeed lived in Africa (H. naledi) and others admixed with Africans not too long ago, providing them with divergent alleles. But, why imagine an African origin at all?

Middle Eastern Origin of Modern Humans

Below is a possible and probable sequence for the origin of modern humans outside of Africa following the timeline given further up.

The first to enter Eurasia were H. erectus, from the Horn of Africa in Ethiopia, across the Middle East to the Caucasus where we find them in Dmanisi, Georgia. The map below (Map 1) shows the source and the destination, as well as a tentative migration route (red arrow). I deliberately painted their territories in different colors, they would become isolated and mutations would differentiate African from Eurasian erectus.

Map 1. Erectus leaves Africa . A. Whittall ©2026

Then, 1.9 to 1.7 Ma., H. erectus migrated westwards into Europe, and east, along southern Asia into Southeast Asia, Sunda, and China. Their remains have been found in Eurasia. In Africa, they must have also migrated though we have no evidence (poor fossilizing conditions in tropical Africa). Map 2 reflects these migrations and the color changes denote evolving differences between the groups. Ice and mountain ranges guide their migration

Map 2. Erectus migrates across Eurasia and Africa . A. Whittall ©2026

Map 3 shows separate evolution of the H. erectus clades ~1.5 Ma., splitting in smaller groups, losing territory in the north as the Ice Ages progress, living in more isolation, and moving to better regions (arrows). Some groups become extinct. All differentiate and diverge. Asian, European, and Africans remain isolated, perhaps some interchange in Gibraltar between North Africa and Spain. Erectus people move into Northern China. The group in the Middle East will become relevant in the following phase.

Map 3. Erectus diversify, and evolve across Eurasia and Africa . A. Whittall ©2026

In Map 4 the evolved Eurasian ancestors of Denisovans, Neanderthals, and Modern Humans located in the Middle East (yellow-black star) see the Neanderthals move out, north and west into Europe and the Caucasus and replacing the other descendants of erectus there, possibly leading to the Sima de Los Huesos individual. Their territories are colored yellow.

The H. erectus in the Far East have modified their territories, becoming extinct in some sites, and evolving. The African descent of the erectus are still living in small groups, moving around the continent, diversifying, evolving. Color changes imply changes in the populations.

Map 4. Neanderthal dispersal (their territory in yellow). A. Whittall ©2026

Map 5 below shows the split that took place 1.38 Ma, centered in the Middle East (star) with Denisovans heading west along a southern coastal route into Asia, the same followed by erectus over 600 ky before them, and their inroads into erectus territories in Sunda and East Asia. They also crossed Neanderthal regions heading towards Central Asia (Altai) mingling with them. The pink color marks Denisovan areas. Africans continue splitting into isolated groups, some very archaic, exchanging genes occasionally. They are many very divergent groups, some are more archaic than the rest.

Map 5. Denisovan dispersal (their territory in pink). A. Whittall ©2026

The final move is the one involving modern humans (Map 6, below) shows how modern humans spread, 1 million years ago, from the Levant, into Africa, admixing with the until then isolated, separated, divergent, archaics there. Into Europe admixing and replacing Neanderthals, and west into Asia. The orange color marks their initial territory as they advance on Neanderthals (yellows) and Denisovans (pink) admixing along the way.

Map 6. Modern Humans dispersal into Africa and across Eurasia (their initial territory is colored orange). A. Whittall ©2026

This, at least, is my take on the subject. Of course, fossils are needed to validate it, and further (improved) genetic tools and models are necessary too.

A very early appearance of humans, would imply that mutation rates are slower than currently estimated, only 1/3 of the accepted rate (because it would have taken 1 My instead of 0.3 My for our species to evolve. With modern humans around 1 My ago, they could have also moved on, into America at any time over the past million years. The problem is, that nobody is looking for such ancient signs.

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall © 

When did we share our last common ancestor with Chimpanzees?

Many molecular clocks are based on the divergence between human beings and chimpanzees. In my previous post I mentioned the calculation method and how it is used to work out the age of a "most recent common ancetstor", based on genetic divergence (mutations), and mutation rates (μ). I pointed out the variability of these μ, today we will look into the age estimations for the most recent common ancestors of humans and chimpanzees, all calculated using genetic molecular clocks, except for the work of Sarich and Wilson back in 1967.

Yes, as expected, there is a wide dispersion of values, frm 4.1 to 13 million years!

This is a summary of the different dates provided by studies over the course of the past 59 years, dates given in million years ago (Ma):

• 5 Ma (Sarich and Wilson, 1967). Used immunological data (albumins and antiserums) in apes and humans.
• 2.7 ± 0.6 Ma (Hasegawa M, Kishino H, Yano T., 1985). They used the mtDNA molecular clock to calculate their dates.
• 5 - 7 Ma (Galina V Glazko, Masatoshi Nei, 2003). Different calibration points, phylogenetic trees, and use of multiple genes and nuclear protein.
• <6.3 Ma (Nick Patterson, Daniel J. Richter, Sante Gnerre, Eric S. Lander & David Reich, 2006). They analized 20 M base pairs of DNA.
• 4.1 ± 0.4 Ma. Speciation time, the MRCA is older. (Asger Hobolth, Ole F Christensen, Thomas Mailund, Mikkel H Schierup, 2007). Used a model comparing ape-human autosomal DNA.
• 7 - 8 Ma K.E. Langergraber,K. Prüfer, et al., 2012. This team measured generation times in wild chimpanzees, used human mutation rate per generation and calculated the split date.
• 12.1 Ma (Priya Moorjani, Carlos Eduardo G. Amorim, Peter F. Arndt, and Molly Przeworski, 2016). Employed autosomal data but of CpG transitions and considered variable mutation rates.
• 7.4 Ma (Schrago and Voloch, 2013). Stepwise analyses of genetic and molecular datasets covering anthropoids.
• 13 Ma (11 to 17 Ma) (Venn et al., 2014). Considers the high mutation rate in male chimpanzees, and assumes it has always been so.
• 6.6 Ma (Guy Amster, Guy Sella, 2016). Modified mutation rates using sex-specific life histories (onset of puberty, generation times in both sexes, and how they changed over millions of years)
• 5.5 - 6.3 Ma (DongAhn Yoo, et al., 2025). They only used segments that could be aligned (ape-human DNA is very diverged) in an incomplete lineage sorting (ILS).

I like the ones that consider variable mutation rates (see my previous post), because it seems more realistic.

Chimpanzee. Source

No fossils

The main problem is that there are no fossils of the ancestor of humans and chimpanzees. There are other ape fossils which have been dated, in Africa and Eurasia, but the exact relationship with the common ancestor of chimps and humans is the subject of intense debate in scholarly circles.

Reasons for not finding fossils: it is not easy to work in Africa, with the common civil wars, warlords, corruption, lack of access to potential sites, funding issues, and also excuse that the tropical African environment isn't the best to create fossils (It baffles me how Java man was discovered in a tropical setting in Asia!)

There are over 6000 fossils of hominins and 31 species (Foley and Lahr, 2024) but just a handful of ape fossils. There are some like the Ororrin, the Sahelanthropus and the Ardipithecus that could belong (or not) to the clade leading to chimps and humans. But Foley and Lahr write that "These groups may be entirely different, representing taxa that belong to none of the extant hominine lineages or they may belong to an early form of African ape, which... overlapped geographically with later hominins." Clearly, the situation is complex and unresolved.

Previously I posted about Miocene (a period spanning 23 to 5-3 Ma) apes found in Europe and Western Asia, and the lack of fossils from Africa suggesting an Eurasian origin for them followed by a migration into Africa as climate turned worse in their homeland. There are some African fossils dating back to the Miocene epoch the oldest date back to the early Miocene (16 to 22 Ma), in Kenya and Uganda, too far from the split of Chimps and Humans to be relevant for our post.

Kunimatsu, 2007 reported an ape from the Late Miocene epoch, named Nakalipithecus nakayamai, its remains were unearthed in Kenya and it "could be close to the last common ancestor of the extant African apes and humans." It was the size of female gorillas and orangutans. The authors dated it to 9.8-9.88 Ma.

Also in 2007, Suwa et al., reported another finding, some teeth with a gorilla-like appearane which were assigned to a new species, Chororapithecus abyssinicus from Chorora, Ethiopia. This great ape was dated to 8 Ma. It is possible that it is related to N. nakayamai.

The Sahelanthropus tchadensis, reported by Brunet et al., 2002, and 2005, was named for the Sahel region of Chad lived 7 Ma. Leg bones and a skull were recovered. We don't know if it is an ancestor of chimpancees and humans or just a separate branch like the Gorillas.

Orrorin lived in Kenya some 6 Ma. It was first described as closer to humans, but later studies placed it close to australopithecines. Almecija et al., (2013) place it as "intermediate between Miocene apes and australopiths".

The Ardipithecus ramidus seems to have evolved after humans and chimpancees separated (4.4 Ma). Partial remains have been recovered in the Afar region of Ethiopia, and it seems to have been adapted to living in the trees, and was also bipedal but not very efficient walking on two feet. It was the size of a chimp, and had a brain equivalent to theirs too. They may have split from the ancestor of the hominini tribe that encompasses humans and chimpancees and not be a direct human ancestor.

Much more recent are chimpanzee fossils, the very first! unearthed by McBrearty and Jablonski (2005) in Kenya, Eastern Africa, far from their current distribution in Central and Western Africa. They lived close to a hominin species, but they are relatively close in time to us, around 545-284 ky old.

Eurasian origin

Finally, I must mention Frances A. M. Mansfield and Mario Vaneechoutte (2024) who propose a Eurasian origin for Chimpancees and Gorillas, this is an unorthodox and thought provoking point of view. I highlighted their comments on Chimpancees.

"While the established paradigm of human evolution asserts that the lineages leading to the extant great apes and Homo arose in Africa, the large number of fossil discoveries from Europe in recent decades support arguments for a European origin of the Hominidae (all great apes) and plausibly, also a European common ancestor of the Homininae (African great apes, Australopithecus species, and the genus Homo).
Meanwhile, a lack of consensus remains regarding the phylogenetic placement of australopithecine fossil species in Africa, with substantial evidence indicating that some of them may align more closely to extant African great apes than to Homo. Based on a novel interpretation of existing fossil, genetic, paleogeographic and paleoclimatic evidence, this paper aims to put forward a new hypothesis regarding the separate divergences of Gorilla, Pan, and Homo.
We support existing arguments that the last common ancestor of African great apes and Homo may have lived in Europe in the late Miocene, and we put forward a new hypothesis as to where, when, and why the separate lineages may have started to diverge. Extreme conditions during the Vallesian Crisis (11.6-8.0 Ma) and the Messinian Salinity Crisis (6.0-5.3 Ma) may have forced separate branches of European hominids to migrate out of the Mediterranean region.
We argue that the lineages leading to Gorilla and Pan independently migrated into Africa, while the lineage leading to Homo went in another direction. Thereafter, the Zanclean Megaflood (5.3 Ma) —which caused the Mediterranean to refill very quickly— may have cut off the migration route between Eurasia and Africa at the Sinai Peninsula, isolating a small population (the putative Homo lineage) on the Arabian Peninsula / Red Sea coast during a period of hyperaridity. The other group (Pan lineage) crossed into Africa, where it subsequently diversified into various species of Australopithecus."

The authors note that "Upon reviewing the descriptions of presumed hominin fossils from Africa from the late Miocene to the early Pleistocene (from Sahelanthropus tchadensis, ~7.0 Ma, through H. habilis, ~2.31–1.65 Ma) one finds, contrary to expectation, that many of the earlier species tend to display a number of presumed derived features, while later species often display more presumed primitive features.... Meanwhile, detailed analyses of Australopithecus fossils reveal that, other than features related to bipedalism, they tend to display many characters more similar to great apes than to humans... Finally, most students of paleoanthropology agree that the earliest Homo erectus/H. ergaster fossil specimens bear marked dissimilarities with any presumed Australopithecus ancestor, which makes it difficult to establish any direct transition or relationship between the two groups."

The Retrovirus

The paper also mentions the strange case of retroviral genes (originating in a virus) that entered the genome of all African primates except Homo (us and our ancestors), this introgressed region known as Pan troglodytes endogenous retrovirus 1 (PTERV1), which is completely absent from the human genome. PtERV-1 is believed to have ocurred 3 to 4 million years ago when the retrovirus infected chimpanzees and gorillas.

The paper states that "This strongly indicates that our ancestors were most probably not even in Africa during the Pliocene (Benveniste and Todaro 1976, Polavarapu et al. 2006), but this is rarely commented upon, and attempts to explain how Homo ancestors may have managed to evade viruses that affected all other extant African apes have proved inconclusive (Kaiser et al. 2007, PerezCaballero et al. 2008). The most parsimonious explanation is that our ancestors were not in Africa during the middle Pliocene and may instead have evolved in “an ecological niche that physically separated them from the source of the infectious PtERV1 virus” (Kaiser et al. 2007b)." They made a good point!

The paper argues the following (a long quote, but worth the while reading it); LCA is the Last Common Ancestor:

"We propose that the species representing the LCA of humans and chimpanzees formed part of a continuous migration of fauna from southern Eurasia to northern Africa during the Messinian, between 5.9–5.3 Ma, via Anatolia and across the northern Sinai region of the Arabian Peninsula. Ultimately, a small group of individuals, ancestral to Homo, may have been cut off and separated from other hominids, ancestral to Pan, when, at 5.33 Ma, the Zanclean flood refilled the Mediterranean and submerged the land bridge between the African and Arabian plates, at which point the connection between the two continents was lost. This date would be consistent with the majority of genetic analyses for the timing of the Pan/Homo divergence. The lineage that made it to the African continent—eventually leading to the Pan lineage—may have migrated south along the African Red Sea and/or Nile River valley and continued southward at Afar, following the many substantial waterways and lakes along the East African Rift Valley and Coastal Forest. This may explain why existing fossil evidence fails to demonstrate a clear progression from primitive/ape-like features towards more derived/human-like features, and why there is no obvious progression from quadrupedalism towards bipedalism in the australopithecines...
We suggest that, unlike the ancestors of australopithecines and extant African apes, the proto-human group remained isolated on the Arabian Peninsula. Between 5.6 and 3.3 Ma, the Arabian Peninsula went through a stage of hyperaridity (Böhme 2021), so any species trapped there would have been isolated between the Red Sea and a lifeless desert—an impenetrable barrier... Unfortunately, there is no fossil evidence to support this scenario... Moreover, the Arabian Peninsula presents a location from where a new genus, Homo, could migrate coastally in multiple directions (Africa to the west, Dmanisi, Georgia to the north, Pakistan, China and Indonesia to the east) only once sea levels fell again in the early Pleistocene, thereby giving rise to multiple variations of Homo erectus/ergaster."

Closing Comments

In this post we have mentioned the wide range and variable dates for the last common ancestor shared by human beings and chimpanzees, which is the outcome of the variability of mutation rate values mentioned in my previous post. We also described the lack of fossils in Africa that could help clearly define the transition between Miocene apes and the first homo individuals. Both genetic and archaeological-paleontological finds offer weak backing to the African origin of our ancestors.

I notice, time and time again, an effort to "fit" or "adapt" findings to the accepted timelines and chronologies, and to support the African origin of the great apes. Perhaps Mansfield and Vaneechoutte are on the right track, and their hypothesis explains the early Georgian fossils at Dmanisi.

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall © 

More papers by Úlfur Árnason on "Out of Eurasia"

My previous post mentioned a paper by Úlfur Árnason against the Out of Africa hypothesis, in which he upholds an Out of Eurasia migration and origin of Modern Humans. I looked for more articles authored by Árnason on this subject. They are listed below:

• A phylogenetic view of the Out of Asia/Eurasia and Out of Africa hypotheses in the light of recent molecular and palaeontological finds. Árnason, Úlfur. (2017) Gene 627. p.473-476. Online, paywall.
• The Out of Africa hypothesis and the ancestry of recent humans: Cherchez la femme (et l'homme). Letter to the Editor. Árnason, Úlfur. (2016) Gene 585, Issue 1, 1 July 2016, p 9-12. Online, paywall.
• Árnason Ú, Hallström B. The reversal of human phylogeny: Homo left Africa as erectus, came back as sapiens sapiens. Hereditas. 2020 Dec 19;157(1):51. doi: 10.1186/s41065-020-00163-9. PMID: 33341120; PMCID: PMC7749984. Online, free access.

A simplified view of Hss dispersal. The shaded area signifies a geographically undefined Asian (Eurasian) area from which Hss dispersed. Mbuti/San mark the earliest Hss exodus into Africa followed by later Yoruba exoduses. The green tracks represent routes that signify potential routes into Southeast Asia and Oceania. Source

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2025 by Austin Whittall ©