BERLIN – A groundbreaking study reveals how early humans adapted to diverse African habitats before their successful global dispersal 50,000 years ago.
Before modern humans embarked on their significant migration out of Africa around 50,000 years ago, they had already settled in ecologically diverse regions. This flexibility may have been crucial for their eventual worldwide spread, according to a new study published in the journal Nature.
Immediate Impact
Our species, Homo sapiens, originated in Africa over 300,000 years ago. Genetic evidence indicates that all non-African modern human populations descend from a small group of humans who began migrating out of Africa approximately 50,000 years ago.
However, earlier research suggests that the initial waves of Homo sapiens left Africa as early as 270,000 years ago, raising questions about why these migrations left no genetic imprints on present-day non-African populations.
Key Details Emerge
In this latest study, researchers analyzed archaeological evidence from sites across Africa dating back 120,000 to 14,000 years. By examining ancient plant and animal remains, they reconstructed the types of habitats and climates humans inhabited during this period.
“Humans have been successfully living in challenging habitats for at least 70,000 years,” said study co-lead author Emily Hallett, an archaeologist at Loyola University Chicago.
The findings show that modern humans began expanding into diverse habitats around 70,000 years ago, including forests in West and Central Africa and deserts in North Africa.
Expert Analysis
This discovery was “a huge surprise” and helps explain why the last major dispersal from Africa was successful, according to study co-senior author Eleanor Scerri from the Max Planck Institute of Geoanthropology in Germany.
“Our ecological flexibility is part of what enabled our species to disperse across the globe and thrive in each habitat we encountered,” Hallett added.
Background Context
Modern humans were adept generalists from the start, occupying a wide range of habitats, noted study co-senior author Andrea Manica, an evolutionary ecologist at the University of Cambridge.
“What we see about 70,000 years ago is Homo sapiens becoming the ultimate generalist, pushing into more extreme environments,” Manica told Live Science.
This adaptability likely gave humans an edge 50,000 years ago, facilitating rapid spread across the globe.
By the Numbers
- 300,000 years ago: Origin of Homo sapiens in Africa
- 70,000 years ago: Expansion into diverse habitats
- 50,000 years ago: Major migration out of Africa
Future Implications
These findings not only illuminate the journey of modern humans out of Africa but also offer insights into human evolution, including ancient lineages like Homo erectus, Neanderthals, and Denisovans.
“Earlier members of our genus must have expanded the range of environmental conditions they occupied when they left Africa,” said William E. Banks, an archaeologist at the French National Center for Scientific Research.
While it remains uncertain why humans began expanding into challenging habitats around 70,000 years ago, one theory suggests shrinking habitable spaces forced this adaptation.
As research continues, the story of human migration and adaptation promises to reveal even more about our species’ remarkable history and resilience.