Homo juluensis — a newly-erected human species that includes enigmatic Denisovans and several hominin fossils from Tibet, Taiwan and Laos — lived in eastern Asia from around 300,000 years ago to 50,000 years ago.
A portrait of a juvenile female Denisovan based on a skeletal profile reconstructed from ancient DNA methylation maps. Image credit: Maayan Harel.
“Our study clarifies a hominin fossil record that has tended to include anything that cannot easily be assigned to Homo erectus, Homo neanderthalensis or Homo sapiens,” said University of Hawai’i at Mānoa Professor Christopher Bae and Dr. Xiujie Wu from the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences.
“Although we started this project several years ago, we did not expect being able to propose a new hominin species and then to be able to organize the hominin fossils from Asia into different groups. Ultimately, this should help with science communication.”
“This work is important because it helps scientists better understand the complex story of human evolution in Asia, filling in some of the gaps in our understanding of our ancient relatives.”
Reconstruction of Homo floresiensis. Image credit: Elisabeth Daynes.
The authors suggest that at least four hominin species — Homo floresiensis, Homo luzonensis, Homo longi, and the newly-established Homo juluensis — were present in eastern Asia during the Late Quaternary period.
Homo juluensis lived approximately 300,000 years ago in eastern Asia, hunted wild horses in small groups, and made stone tools and possibly processed animal hides for survival before disappearing around 50,000 years ago.
“Thanks largely to a growing hominin fossil record, the field of Late Quaternary eastern Asian paleoanthropology is in the midst of significant and important change that is contributing tremendously to how we view and are refining these evolutionary models,” the researchers said.
“In particular, the field received a jolt two decades ago with the publication of the diminutive Homo floresiensis fossils from the island of Flores in Indonesia in 2004.”
“More recently, another diminutive species, Homo luzonensis, from the island of Luzon in the Philippines was added as a new hominin species.”
“In China, Homo longi was presented following an analysis of the Harbin fossil.”
“Fossils like Dali and Jinniushan may be tentatively included in Homo longi as well, though we await further comparative analyses.”
“Most recently, after a detailed study of the Xujiayao and Xuchang fossils, we have added Homo juluensis to these discussions.”
A reconstruction of Homo longi in his habitat. Image credit: Chuang Zhao.
Importantly, the scientists also assign the enigmatic Denisovans, along with the Xiahe, Penghu, and Tam Ngu Hao 2 fossils, to Homo juluensis.
More research is clearly needed to test this relationship, which is primarily based on similarities between jaw and teeth fossils from these different sites.
“The eastern Asian hominin fossil record is an excellent example of how unilineal models of evolution, such as traditional multiregionalism, cannot adequately explain the complexity in the paleoanthropological record, particularly during the Late Quaternary,” the authors concluded.
“If anything, the eastern Asian record is prompting us to recognize just how complex human evolution is more generally and really forcing us to revise and rethink our interpretations of various evolutionary models to better match the growing fossil record.”
Their paper was published in the journal Nature Communications.
_____
C.J. Bae & X. Wu. 2024. Making sense of eastern Asian Late Quaternary hominin variability. Nat Commun 15, 9479; doi: 10.1038/s41467-024-53918-7
