A recent study analyzed pollen data around Lake Baikal in Siberia to reveal details of early human migrations across Eurasia 45,000-50,000 years ago. This evidence suggests that rising temperatures supported the expansion of forests and facilitated human migration into Siberia, contradicting some previous archaeological ideas.
The mystery of human migrations during the Ice Age has long been a subject of debate among anthropologists: When and how did the movement of Homo sapiens across Eurasia occur? Was it a cold or warm current that drove early humans to migrate from Africa to Europe and Asia?
A recent study published in Science Advances explored this question by examining Pleistocene vegetation communities around Lake Baikal in Siberia, Russia, and comparing them to the earliest archaeological evidence of Homo sapiens from the region. Researchers used this important evidence to tell the story from 45,000 to 50,000 years ago, revealing how the earliest humans traveled across Eurasia.
New pollen data show that warming temperatures supported the expansion of forests into Siberia and facilitated the migration of early humans there, at the same time that changes were occurring across more of Eurasia and into the west.
Ted Goebel, professor of anthropology at the University of Kansas, said: "This study resolves a long-standing debate about the environmental conditions that early Homo sapiens faced when they migrated to Europe and Asia approximately 40,000 to 50,000 years ago. It uses pollen records to reveal the amazing warmth of this period, providing crucial insights into the environmental conditions of Lake Baikal."
In fact, pollen data suggest that human migration occurred during the late Pleistocene during a period of warmest temperatures and higher humidity. Ancient pollen records show that taiga and grasslands characterized the region and supported human foraging and hunting. Goebel said environmental data combined with archaeological evidence tell a new story.
"This contradicts some recent archaeological views in Europe." The key factor here is accurate dating, not only of the human fossils and animal bones relevant to the archeology of these people, but also of environmental records, including pollen. What we present is a robust chronology of environmental changes in Lake Baikal during this period, supplemented by the archaeological record of the presence of Homo sapiens in the region.
Goebel's collaborators include first author Koji Shichi of the Kochi Institute of Forestry and Forest Products, Japan, Masami Izuho of Tokyo Metropolitan University in Hachioji, Japan, and Kenji Kashiwaya of Kanazawa University in Kanazawa, Japan.
Although the pollen analysis was conducted in Japan, Goebel and Izuho linked the pollen data to important evidence in the archaeological record of early human migrations. The emergence of mature Homo sapiens in the archaeological record corresponds to changes in culture and behavior, Goebel said. Early modern humans of this period crafted stone tools with long, slender blades and crafted tools from bone, antler, and ivory, including some of the earliest bone needles carved with holes for sewing, and early bone and antler spear points.
"Some of us believe that changes in anatomy were accompanied by shifts in behavior and cognition, as evidenced by the fossil record," Goebel said. "These early humans became more creative, innovative and adaptable. This is when we began to observe significant changes in the archaeological record, such as Cave paintings. We also find moving art, such as early carvings known as Venus statues. There is even an ivory carving dating from this early period of a lion-headed man. It was not just about copying nature, but about creative expression, inventing new things, exploring new places."
According to the University of Queensland researcher, at least one human skeleton dating back to that era has been found in the area.
"There is a human fossil from Siberia, not from Lake Baikal, but further west in a place called Ust-Ishim. Morphologically it is human, but more importantly, it is exceptionally well preserved," Goebel said. "It has been directly radiocarbon dated and produced ancient DNA, confirming that it is a representative of modern Homo sapiens, as distinct from Neanderthals or Denisovans, or other pre-modern hominins."
The region's earliest human inhabitants likely lived in large families or small tribes, as appears to be the case in other parts of Eurasia. But it's difficult to say for sure because much of the archaeological evidence has deteriorated.
He said: "At Ust'-Ishim in Siberia we have evidence that fully modern humans coexisted with the sites we have been discussing. However, Ust'-Ishim is an isolated find, discovered by geologists from river bank erosion. We lack information about its archaeological context. information, whether it was part of a settlement or just a lone skeleton that washed downstream. So the connection between this single individual and the archaeological site in the Baikal region is not strong - do they represent the same population? We think so, but more evidence is definitely needed."