Scientists use pollen data to decode first humans' migration into Eurasia

New Delhi: Pollen grains analysis helps understand how the first humans migrated from Africa across Europe and Asia, research in Science Advances says.

The pollen data showed that warming temperatures supported forests that expanded into Siberia and facilitated early human migration there, researchers from the University of Kansas, US, said in their study.

They compared Pleistocene vegetation communities around Lake Baikal in Siberia, Russia, to the oldest archeological traces of Homo sapiens in the region. The Pleistocene period is considered two million to 11 thousand years ago and as the time of human evolution.

In this study, the researchers use the "remarkable evidence" to tell this migration story from about 45,000-50,000 years ago.

"This research addresses long-standing debates regarding the environmental conditions that early Homo sapiens faced during their migration into Europe and Asia around 40,000 to 50,000 years ago," said co-author Ted Goebel, professor of anthropology at the university.

"It provides critical insights into environmental conditions at Lake Baikal, using pollen records to reveal surprising warmth during this period," said Goebel.

Dispersal of people occurred during some of the highest temperatures in the late Pleistocene, which also would have featured higher humidity, the ancient pollen record suggested, said the researchers, adding it also showed that coniferous forests and grasslands characterised the region, supporting foraging and hunting by humans.

However, the environmental data, combined with archeological evidence, tell another story, said Goebel.

"This contradicts some recent archaeological perspectives in Europe," said Goebel.

"The key factor here is accurate dating, not just of human fossils and animal bones associated with the archaeology of these people, but also of environmental records, including from pollen.

"What we have presented is a robust chronology of environmental changes in Lake Baikal during this time period, complemented by a well-dated archaeological record of Homo sapiens' presence in the region," said Goebel.

The researchers also connected the pollen data to evidence in the archeological record of early human migration.

Goebel said the emergence of full-fledged Homo sapiens in the archaeological record corresponds to changes in culture and behaviour.

Early modern humans of this period were making stone tools on long, slender blades, working bone, antler and ivory to craft tools — including some of the first bone needles with carved eyelets for sewing and early bone and antler spear points, the researchers said.

"Some of us argue that as the anatomical changes were occurring, as evidenced by the fossil record, there was a simultaneous shift in behavior and cognition," said Goebel.

"These early humans were becoming more creative, innovative and adaptable. This is when we start to observe significant changes in the archaeological record, such as cave paintings. We also find mobile art, like the early carvings known as Venus figurines.

"In Central Europe, there's even an ivory sculpture dating back to this early period, depicting a lion-headed man. It’s not just replicating nature; it's about creative expression, inventing new things, exploring new places," said Goebel.