A paper published last week, on Sept. 30th, by archaeologists from La Trobe University, (Martin, J. M., Leece, A. B., Baker, S., Herries, A. I. R., & Strait, D. S. (2026). New hominin cranial and mandibular remains from Drimolen Main Quarry, South Africa. Annals of Human Biology, 53(1). https://doi.org/10.1080/03014460.2026.2725046) described the remains of bones discovered at the Drimolen site. They reached some interesting conclusions.
Drimolen Site
This site is located in a hotspot (there are other similar aged sites nearby —Sterkfontein, Swartkrans, Kromdraai, Coopers), see Google Map. The area is a UNESCO World Heritage site known as "Cradle of Humankind". The place, a quarry, was discovered in 1992, by chance by an amateur archaeologist named André Keyser in 1992. Diggings at the quarry found teeth, jaws, fragments of crania of different hominins, including unidentified Homo species, and Paranthropus robustus. The age of the remains spans a period from 1.5 to 2 million years ago.
The site was an old cave, that was infilled with sediments over the years, and into which animals and hominins fell, and were preserved in the dirt, that became a rock known as breccia (a conglomerate of sharp pebbles cemented together by fine graind sands). This setting, plus the fact that it was a lime quarry, makes me wonder if the old dates assigned to the specimens are accurate. See Herries et al., 2020 who describe the sediments, the now exposed remains of the cave, erosion, quarry alterations, etc. Which tend to downplay disturbed sedimentation, but confirm my suspicions that the site's dating could be skewed to antiquity to favor the OOA theory.
The remains have been described in different papers over the years, and this one is the most recent publication, that describes and identifies the species to which several fossils belong.
The authors identify one of the fossils, named DNH 127, as not belonging to the Paranthropus or the Australopiths. It is assigned to the erectus genus.
It was found in a block of rock that may have been part of a pinnacle (DNH 7) which had been dated (this shows that the dating of the remains is tentative, some fossils were found in situ, in the beds of sediments, others in loose soil. After all, this was a quarry and has disturbed rock beds).
They give it the same age given to the other specimens found in the DNH 7 bed. There was an erectus in the site, DNH 134, so scholars expected to find more. This paper assigns the DNH 127 remains to the Homo erectus group, and date it to ~1.98 million years ago.
Link with Dmanisi
Interestingly, they note that "Heuristically, the morphology preserved by DNH 127 most closely resembles that of D2700 from Dmanisi. Based on this mosaic of traits, we tentatively assign DNH 127 to Homo erectus sensu lato." This is revealing, Dmanisi in Georgia, is in the Caucasus, 9,200 km (5,700 mi) away, and it is the site with the oldest crania of Homo erectus in Eurasia. Their age is slightly younger than the age given to the Drimolen Cave specimen (at 1.8 million years old). But, since it was dated based on a conjectural belonging to a given pinnacle, it may be possible that the date is not precise. If so, the Dmanisi remains could be older, or possibly there are older remains yet to be discovered in Georgia. In this case, we could imagine a migration into Africa, from Eurasia, that reached South Africa 1.98 million years ago. The vanguard of these migrants met and coexisted with Paranthropus in this area.
By the way it is interesting how Herries et al., 2020 stress that the Drimolen erectus is older than Dmanisi. Like they need to reinforce the OOA and African origin of Homo genus: "At ~2.04 Ma ago (minimum age 1.95 Ma), DNH 134 is the most complete and oldest early Pleistocene Homo neurocranium in South Africa. DNH 134 is at least 100,000 to 150,000 years older than H. erectus s.l. specimens from Dmanisi... As such, DNH 134 represents the oldest fossil with affinities to H. erectus in the world. Despite this, we do not assert that the species necessarily evolved first in southern Africa, especially given major geological biases in hominin finds across Africa. However, the dating of the DNH 134 cranium to >1.95 Ma ago substantially weakens the hypothesis that H. erectus sensu lato evolved outside of Africa."
Other unclassified hominins
The paper also mentions that specimens SK 847 and StW 53 have not been classified yet, which "leaves open the possibility that more than one species of Homo may have been present on the landscape in southern Africa ∼2.0 Ma" It states that dental traits have led other authors to assign them to "Homo sp. indet. [but], there is not yet unequivocal evidence to suggest that more than one species of Homo is present within the DMQ assemblage" If so, there would be three or more species there (the other two being erectus and Paranthropus).
A 10 to 1 ratio of Paranthropus to erectus
The unusual ratio of bones between primitive Paranthropus and more evolved Homo erectus.
Although the paper itself does not mention this, it is noted in the University's media release (titled Fossils confirm human ancestors first appearance). In it, one of the coauthors of the paper is quoted as follows regarding Paranthropus and erectus (highlight is mine):
"... “These two human species shared the same landscape and are both preserved in Drimolen cave. While we know that Homo erectus and the lineage leading to us was ultimately the successful one, 2 million years ago P. robustus outnumbered Homo erectus at Drimolen by more than 10 to one. During this time period it was our ancestors that looked like the outside long-odds chance to survive,” Dr Martin said."
This remark drew my attention, why would one species outnumber the other ten to one? It seems that Paranthropus was well adapted to this location, its habitat and environment allowed them to proliferate and grow into a large, well established population. Primitive, the Paranthropus living in this area had larger teeth and jaws, forming a distinct species from other members of the group. This specific adapatation show that they were successful, and the dominant primates in this area.
The fewer erectus remains, however, seems to suggest that they were newcomers. They appear suddenly in the fossil record here, with few members and this hints at recent arrival, a migration of a small population (maybe from the northeast, spreading into a new territory).
The Homo group would be far more successful than Paranthropus but 2 million years ago, they were sharing their new home with very well adapted primates who outnumbered them ten to one.
It is likely that they exploited different resources from their habitat, perhaps the erectus were meat-eaters and gatherers, they made stone tools (though none have been reported here at Drimolen). The Paranthropus were apes, similar to chimps, who may have eaten plants, fruit, and tubers.
The Drimiolen quarry site suggests that erectus was a newcomer to South Africa, it does not prove that they were migrants, and it does not prove that they originated there, in South Africa. Their age, barely older than the oldest Eurasian erectus is used to suggest an African origin for erectus. But, it can't disprove an Eurasian origin and migration into Africa.
Further discoveries will clarify the mystery of the origin of erectus.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2026 by Austin Whittall ©
No comments:
Post a Comment