Central Asia identified as a key region for human ancestors

The interior of Central Asia has been identified as a key route for some of the earliest hominid migrations in Asia in a new study led by Dr. Emma Finestone, Assistant Curator of Human Origins at the Cleveland Museum of Natural History and Affiliate of Max Research Planck Institute for the Science of Human History.

The study findings indicate that the steppe, semi-arid and desert areas of Central Asia were once favorable environments for hominins and their dispersal into Eurasia.

An interdisciplinary team of scholars from institutions spanning four continents set out to expand limited knowledge of early hominin activity in lowland Central Asia. The team included Dr Paul Breeze and Professor Nick Drake from King’s College London, Professor Sebastian Breitenbach from Northumbria University in Newcastle, Professor Farhod Maksudov from the Uzbekistan Academy of Sciences and Professor Michael Petraglia from the University of Griffith in Queensland, Australia.

“Central Asia connects several areas that played important roles in the dispersal of hominins out of Africa and across Asia,” said Dr. Finestone. “However, we know comparatively little about the early occupation of Central Asia. Most archaeological material is undated and detailed paleoclimate records are scarce, making it difficult to understand the dynamics of early hominin occupation and dispersal in that region.”

The team compiled and analyzed paleoclimatic and archaeological data from the Pleistocene (approximately 2.58 million years ago to 11,700 years ago) in Central Asia. This included the construction of a dataset of Paleolithic stone tools and the analysis of a mineral deposit that formed in a cave (a stalagmite) in southern Uzbekistan. Tool making and modification are key to the human ability to migrate to new environments and overcome environmental challenges. Ancient hominins moved their tools with them as they dispersed. The researchers studied the location of the stone tools and the environmental conditions that were reflected by the stalagmite as it grew at the end of Marine Isotopes Stage 11 (a warm period between the MIS 12 and MIS 10 glaciers) about 400,000 years ago. .

Dr. Maksudov of the Uzbekistan Academy of Sciences said relatively little is known about the region’s earliest toolmakers because most occurrences are from the Lower Palaeolithic (the oldest subdivision of Palaeolithic stone tools) in Asia. Central lack a reliable context for dating and environmental reconstruction.

“Despite the potential importance of Central Asia for early dispersals, our knowledge of the Lower Palaeolithic in this vast and diverse landscape has been limited.”

“We collected data on Palaeolithic finds from across Central Asia, creating a dataset of 132 Palaeolithic sites, the largest dataset of its kind,” said Professor Petraglia, lead author of the study. “This allowed us to consider the distribution of these sites in the context of a new high-resolution speleothem-based multiple proxy record of hydrological changes in southern Uzbekistan since the Middle Pleistocene.”

“Cave deposits are incredible archives of the environmental conditions at the time of their growth. Using geochemical data from stalagmites, we gain insights into millennial-scale seasonal changes in moisture availability and the climate dynamics that govern rainfall and snowfall.” Our work suggests that the local and regional conditions did not follow simple long-term trends, but were rather variable.” said Professor Breitenbach, who led the stalagmite-based analysis.

“We argue that Central Asia was a favorable habitat for Palaeolithic toolmakers when warm interglacial phases coincided with periods when the Caspian Sea experienced consistently high water levels, resulting in increased moisture availability and more temperate conditions. in arid regions,” said Dr. Finestone. “The pattern of the stone tool sets also supports this.”

During periodic warmer and wetter intervals, the local environment of arid central Asia might have been a favorable habitat and was frequented by Lower Palaeolithic toolmakers who produced bifaces (stone tools that have been worked on both sides).

“Interdisciplinary work bridging archeology with paleoclimate models is becoming increasingly necessary to understand human origins,” said Dr Finestone. “In the future, the databases generated in this study will continue to allow us to ask questions about the context of hominin dispersals.”

The research ‘Paleolithic occupation of the arid zones of Central Asia in the Middle Pleistocene’ has been published in PLUS ONE.