The first hominins to leave Africa were discovered in Georgia, in the Caucasus. A paper published in March 2025 suggests that not all the remains of found in the cave in Georgia belong to this Homo georgicus species, and tries to place these specimens on the hominin phylogenetic tree.
I have posted on H. georgicus in 2011 and 2019. But science advances and new discoveries arise so it is time to take another look at Georgicus.
Source: Where do the Dmanisi hominins fit on the human evolutionary tree? Debbie Argue, José María Bermúdez de Castro, Michael S. Y. Lee, Maria Martinón-Torres bioRxiv 2025.03.01.639363; doi: https://doi.org/10.1101/2025.03.01.639363
I quote part of their paper below.
"Conclusions
The Dmanisi hominins are often included in H. erectus or H. erectus s. l. /H. ergaster, notwithstanding that they are formally designated as Homo georgicus with D4500_D2600 as the holotype. In our phylogenetic analyses, none of the Dmanisi hominins form a sister taxon to either H. erectus or H. ergaster. We hypothesise that the Dmanisi hominins did not share a unique common ancestor with H. erectus or H. ergaster, and we cannot support their attribution to either of those species.
Although all the Dmanisi hominins are attributed to a single species, the morphological variation evident among them has prompted questions about their heterogeneity with discussion focusing on whether one species or two are represented. We approached this question using phylogenetic analyses and by exploring further lines of evidence. Although our phylogenetic analyses did not lead us to propose two species among the Dmanisi hominins, there are nevertheless morphologically significant differences in the cranium, mandible and dentition of the individual represented by D4500_D2600 and the other Dmanisi hominins that are consistent with the view that D4500_D2600 represents a separate species. These are the unique and perplexing pattern of sexual dimorphism evident in the endocranial capacities of the assemblage when considered as one species; the dichotomy in mandibular molar size sequences; and in the presence of both a primitive and a derived form in the mandibular structures among the assemblage. We also note that D4500_D2600, in terms of character distances, is more similar to other hominins, including H. floresiensis, than it is to the other Dmanisi individuals.
We propose that the most parsimonious hypothesis for the Dmanisi hominins is that two species are present among the assemblage: Homo georgicus comprising D4500_D2600 and an un-named species comprising the other Dmanisi hominins: D2280, D2282_D211, D2700_D2735 and D3444_ D3900. The alternative hypothesis, that the assemblage comprises a single species, requires substantial paradigm shifts in our definition of Homo.
We surmise that the first hominin species at Dmanisi was H. georgicus, and that the species was probably present by 1.8 Ma. The other hominins, D2280, D2282_D211, D2700_D2735 and D3444_ D3900, accumulated at some time or times during the reverse polarity of 1.07 Ma and 1.77 Ma.
The specific ages of D2280, D2282_D211, D2700_D2735 and D3444_ D3900, however, remain unknown. Dating of the volcanic ashes in which each hominin was recovered, together with dating the ashes in the overlying strata to find the minimum date for the hominins, would likely produce a more refined understanding of the chronology for the Dmanisi hominins."
The link to the Flores Island hobbit is interesting, and also the lack of relationship with H. erectus and H. ergaster. Who, as we see below are more recent. The phylogenetic trees in the paper suggest that H. georgicus is on a branch that split earlier from the one leading to H. habilis, H. erectus, H. ergaster, and H. sapiens. Pictured below
Ancient Hominins in Eurasia
Georgicus was the first early hominin to be discovered in Eurasia, and older than the H. erectus remains found in Indonesia and China. They were the first to venture out of Africa.
But Georgicus wasn't alone in Eurasia. There are many sites around 2 million years old. Some of them have hominin remains associated to them, others have tools or bones suggesting human action on them. See this paper published in Nature in January 2025 as an example. It includes the following image with ancient sites and what markers were used to identify hominin presence (Fig. 5). Note that the other "oldest" remains found are H. erectus, suggesting that Georgicus came first.
So, which ancient hominin left Africa? Was it H. georgicus if he appeared in Africa and migrated to the Caucasus, or even more primitive australopithecines that evolved into H. georgicus in Asia?
Ferring et al. (2011) suggested that Georgicus predates H. erectus in Africa: "Dmanisi's first occupations to shortly after 1.85 Ma and document repeated use of the site over the last half of the Olduvai subchron, 1.85–1.78 Ma. These discoveries show that the southern Caucasus was occupied repeatedly before Dmanisi's hominin fossil assemblage accumulated, strengthening the probability that this was part of a core area for the colonization of Eurasia. The secure age for Dmanisi's first occupations reveals that Eurasia was probably occupied before Homo erectus appears in the East African fossil record."
Argue et al. confirm it with their phylogenetic trees. Homo georgicus was not a subspecies of erectus, it was located on a branch that split from some common ancestor of Homo habilis and later H. erectus.
Did a back-migration into Africa of the Georgicus hominins lead to the appearance of H. habilis there? In that case it would be an In &: Out of Eurasia-Africa that led to more evolved hominins.
Further studies will provide additional information.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2025 by Austin Whittall ©
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