Today's post shares a paper on the dispersal and evolution of hominins in Eastern and Southeastern Asia. It has plenty of interesting insights on the time line and geographic dispersal of our ancient ancestors in Asia.
The paper is the following: Rikai Sawafuji, Takumi Tsutaya, Naoyuki Takahata, Mikkel Winther Pedersen, Hajime Ishida, (2024). East and Southeast Asian hominin dispersal and evolution: A review. Quaternary Science Reviews. Volume 333, 1 June 2024, 108669. https://doi.org/10.1016/j.quascirev.2024.108669.
It summarizes current knowledge, and theories, as well as suggesting some future research avenues. A very good paper!
I enjoyed the description of Homo erectus. This hominin has always fascinated me since I was a teen, when I read about it in my elder sister's highschool biology book (no internet in the 1970s). At that time there was the Peking Man, and the Java Man from Solo Rivr, and no African erectus. I also read about the Rhodesia Man, Neanderthals, Cro-Magnons, and the Australopithecines in Africa, more primitive and smaller. It seemed a complex mixture of different people. Now, over 50 years later, the panorama is still obscure!
"There are various views on the classification of H. erectus, e.g., H. erectus from Africa as a separate species called H. ergaster (Tattersall et al., 2015). In this review, we use the broader definition of H. erectus (H. erectus sensu lato) and consider the African H. erectus as part of the same taxon.
H. erectus is currently recognized as the first hominin to spread out of Africa and is thought to have migrated eastward across Eurasia and then southward into Southeast Asia. The fossil records are concentrated in Europe, China, and Java, with little data available for the intermediate areas.
Some of the earliest probable fossils of H. erectus are the ∼2.04 Ma cranium found at Drimolen, South Africa (Herries et al., 2020) and ∼2 Ma mandible at Melka Kunture, Ethiopia (Mussi et al., 2023), while the earliest generally accepted evidence of their presence out of Africa was discovered at Dmanisi, Georgia, and dated to ∼1.8 Ma (Ferring et al., 2011; Lordkipanidze et al., 2013).
In China, recent findings have suggested an earlier hominin presence although the evidence is scarce and primarily based on stone tools found at Shangchen, dated to ∼2.1 Ma (Zhu et al., 2018), and on hominin teeth dated between 2.42–1.8 Ma at Jianshi-Longgu Cave (Li et al., 2017a). These findings, which might predate the Dmanisi fossils, suggest the intriguing possibility that either H. erectus or another hominin arrived in China earlier than the time of Dmanisi (Cartmill and Smith, 2022). However, due to the scarcity of comprehensive fossil records, these conclusions must be approached with caution, as definitive identification of these early hominins in China remains challenging.
Fossils and lithics of likely H. erectus found in China include ∼1.66 Ma stone tools from Majuangou III in the Nihewan Basin (Zhu et al., 2004) and 1.7–1.6 Ma stone tools from Shangshazui (Ao et al., 2013), and a ∼1.63 Ma cranium from Lantian-Gongwangling, near Shang Chen (Zhu et al., 2015). Two ∼1.7 Ma incisors have also been found in Yuanmou, South China (Zhu et al., 2008), though their age determination remains questioned (Bae, 2010). Taken together with the fossil and lithic evidence, the conservative age of the emergence of H. erectus in China is about 1.7–1.6 Ma."
The interesting part is the suggrestion of hominin presence in China ~2.4 to 2.1 Ma, older than the earliest South African fossils (~2.04 Ma), also that they were not Homo erectus but "...another hominin arrived in China earlier than ... Dmanisi." This could imply the presence of Homo habilis or even Australopithecines in Asia.
The following image shows how the different lineages of hominins coexisted in Asia during the past 2 million years.
The image below shows the distribution of hominins in Eastern and Southeastern Asia/p>.
The Story and Timeline of Hominins in Asia
The paper gives a brilliant description of the dispersal of hominins in East Asia and Southeast Asia.
"As more and more pieces are continuously added to our understanding of hominins, their geographical distribution and persistence, new questions arise, and details about how the different hominins dispersed and why they went extinct still remain unclear. From current fossil records and genetic evidence, one plausible and coherent scenario of hominin dispersal is the following: H. erectus emerged in Africa and expanded into the Eurasian continent around 2 Ma, later occupying Europe, East Asia (China) and Southeast Asia (Java).
Subsequently, the common ancestor of H. sapiens, Neanderthals and Denisovans split into two groups: one was in Africa (later leading to H. sapiens) and the other settled around the Middle East at some point. The latter interbred with a super-archaic hominin group (possibly H. erectus) around 700–600 ka.
The Eurasian hominin group then split into two groups. One settled in the West (Europe and Western Asia) leading to Neanderthals, while the other settled in Asia leading to Denisovans. Denisovans interbred with H. erectus in Eurasia, occupying their niche. At some point, Denisovans also expanded into East and Southeast Asia, where the groups diverged into different subgroups (D0, D1, D2, D3, the details are in the chapter of Denisovans). Meanwhile, H. erectus may have become extinct around 400 ka in East Asia and 100 ka in Southeast Asia. Denisovans reached the Altai region, eventually meeting and interbreeding with Neanderthals several times around 140–80 ka. Meanwhile, some H. sapiens left Africa before 200 ka. This initial migration was unsuccessful, but interbreeding with Neanderthals at this time left traces in their genome (Peyrégne et al., 2023). There were several subsequent out-of-Africa events, which might have reached Asia, but the populations that led to our ancestors left Africa around 55 ka. They interbred with Neanderthals in West Asia and with Denisovans in EA/SEA. Note that we consider the super-archaic hominin contributing to the Denisovan genome to be H. erectus. While there is a possibility that hominins other than H. erectus and Denisovans migrated into Asia or evolved from H. erectus, this is not considered here due to the lack of evidence."
The suggestion that (no date given for this event) the ancestor of modern humans, Neanderthals and Denisovans moved out of Africa, settled in the Middle East and some 700-600 ya mating there with H. erectus is very interesting!
The further admixing of Denisovans with erectus as they moved across Eurasia is not often mentioned. And the final comment that "... there is a possibility that hominins other than H. erectus... migrated into Asia or evolved from H. erectus," is worth exploring as there is no evidence to prove it happened. But, it is possible and likely.
The paper also has some interesting comments on the four lineages of Denisovans (with a neat map), and their history:
Denisovans
"The common ancestor of Denisovans and Neanderthals which occupied around the Middle East interbred with a super-archaic hominin, and afterwards the Denisovan ancestors diverged from the Neanderthal ancestral group and moved into Asia. Some of them spread towards Papua and settled in Island Southeast Asia (D1). Another group remained in South or Southeast Asia (D2), and from there, another group moved further north into East Asia (D0, D3). During the early phase of this migration, they encountered a super-archaic hominin population and interbred. The D0 group settled somewhere in East Asia. The D3 group reached the Altai in Siberia (D3), where they met and interbred with Neanderthals."
The section dedicated to small-sized hominins Homo floresiensis and Homo luzonensis is great, I learned that the latter's "finger and toe bones are elongated and curved, a feature similar to australopithecines". Nevertheless, evidence suggests both "tiny" hominins may descend from H. erectus.
Ancient Mariners
It is remarkable that these two groups of people (and a third responsible for stone tools found in Sulawesi) crossed open sea, settled in islands, and lived there in isolation until their demise when modern humans reachd the area. Navigating abilities is something seldom discussed in any paper, including this one, which only says "Although it is unclear how each hominin crossed the sea, they succeeded intentionally or accidently"
It is evident that even archaic forms of hominins like erectus crossed open sea. Could they have reached America? (See my post about their navigating skills, and this post on Neanderthal "sailors").
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall ©
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