An article published in the journal “Nature Communications” reports comments on the variability of hominins that inhabited East Asia between 300,000 and 50,000 years ago and the proposal of a new species named Homo juluensis that includes fossils discovered in various parts of Asia, including those attributed to the Denisovans. Professor Christopher J. Bae of the University of Hawaii at Mānoa and Xiujie Wu of the Chinese Academy of Sciences attempted to bring order to the organization of Asian hominin fossils from the Late Quaternary with the aim of creating a clearer system for understanding the human species that lived in Asia.

The image (Courtesy Bae, C.J., Wu, X. / Nature Communications) shows a scheme of the organization of the fossils of Asian hominins from the Late Quaternary proposed by the two authors of this study. Some, such as the so-called Maba man (China) and the Narmada fossil (India), have an attribution that is still uncertain. The Hualongdong population (China) is also difficult to attribute due to the set of anatomical characteristics.

In recent decades, the discovery of fossils showing remarkable anatomical variability in different areas of Asia has led to the proposal of new species within the genus Homo and to discussions around the attribution of other fossils. Over the years, the species Homo floresiensis, Homo luzonensis, and Homo longi were proposed.

In all this, Denisovans are a paradoxical case, in the sense that they are the best and worst known hominins at the same time. That’s because there are very few bones attributed to this ancient human species, but the bones found in Siberia were in an excellent state of preservation, to the point that it was possible to extract many pieces of DNA.

Some fossils discovered in Tibet and Laos were attributed to Denisovans based on anatomical similarities, while other Asian fossils remained the subject of discussion due to the difficulty of attributing isolated bones. Christopher J. Bae and Xiujie Wu had discussed the possibility that these and other fossils such as those from Xujiayao and Xuchang (in China) and Penghu (in Taiwan) represented a single form of hominins with a large brain they nicknamed Juluren. In an article published in May 2024 in the journal “Paleoanthropology”, the two scientists discussed this possible species.

Now, in the article published in “Nature Communications” the two scientists expanded the discussion to the various species of hominins that lived in eastern Asia in the Late Quaternary, between 300,000 and 50,000 years ago. The article is interesting for the organization of the fossils described and for the proposal of the species Homo juluensis. The two scientists tried to clarify the fossils that couldn’t be assigned to the species Homo erectus, Homo neanderthalensis, or Homo sapiens.

The studies by these and other researchers who are trying to reconstruct the history of humanity have been greatly expanded by the discoveries made in recent decades. However, they remain complex due to the scarcity of fossils from eras that could be very important and because obtaining DNA from the discovered bones is an exceptional event.

Christopher J. Bae and Xiujie Wu also mentioned the probability that some Asian populations of hominins were the result of interbreedings in which hybrids transmitted some characteristics of one species to another. Precisely thanks to the exceptional possibility of obtaining the DNA of some Denisovans, we know that their genetic traits are widespread in today’s populations of East Asia.

Even more numerous interbreedings between different human species could have given rise to the Hualongdong population, discovered by the two authors of this study, who describe it together with other colleagues in an article published in March 2019 in the journal “Proceedings of the National Academy of Sciences”.

Every proposal for a new hominin species brings discussions that can be constructive if it helps to bring some order. Christopher J. Bae and Xiujie Wu are aware that the history of humanity is intricate, marked by migrations and interbreedings of populations with all the complications that ensue. The proposal of the species Homo juluensis could at least give a place to some ancient populations, including the Denisovans.