Climate Change A Hidden Factor In Human Evolution For Over 2M Years
The course of human evolution over the last 2 million years was shaped by habitation shifts linked to astronomically driven climate change, scientists from the Pusan National University in South Korea suggested in a new study, Peter Dockrill reported for Science recently.
Photo Insert: The study also argues that shifts in human adaptation cannot be fully explained without recourse to a broader understanding of climatic factors affecting ecosystems.
Using an unprecedented supercomputer simulation of Earth's climate as it transitioned through climatic shifts over the course of the Pleistocene epoch, researchers found that changes in variables such as precipitation and temperature were linked with how a range of different hominin species, including Homo sapiens, settled or wandered over eons of human prehistory.
The study was also published in the journal Nature.
"Even though different groups of archaic humans preferred different climatic environments, their habitats all responded to climate shifts caused by astronomical changes in Earth's axis wobble, tilt, and orbital eccentricity," says climate physicist Axel Timmermann from Pusan National University in South Korea.
The results add weight behind the argument that prehistoric episodes of climate change spurred evolutionary developments in the Homo genus – a long suspected but difficult-to-prove hypothesis due to a lack of hard climatic data overlapping contemporaneously with discoveries of archaic humans in the fossil record.
"Our study documents that climate played a fundamental role in the evolution of our genus Homo," Timmermann says. "We are who we are because we have managed to adapt over millennia to slow shifts in the past climate."
As one example, the researchers suggest that climate stress in southern Africa could have been what led to the rise of H. sapiens, while H. heidelbergensis went extinct.
Beyond suggesting that climate data played a role in human evolution, the study goes even further, arguing that shifts in human adaptation cannot be fully explained without recourse to a broader understanding of climatic factors affecting ecosystems.