Supercomputer simulations show climate change’s role in early human migration

The environmental conditions that our ancestors faced are a key factor in the expansion of humanity. A research team from South Korea's Pusan National University revealed research from supercomputing modeling that shows how much of humanity's rise is due to changes in prehistoric weather.

The Pusan team used an unprecedented combination of a general circulation model simulation and an extensive collection of fossil and archaeological records to study the habitat suitability for five hominin species.

The 2ma simulation reproduces key paleoclimate records such as tropical sea surface temperatures,Antarctic temperatures, the eastern African hydroclimate and the East Asian summer monsoon in close agreement with paleo-reconstructions.

The team was looking at how the 41,000-year pattern of precipitation and temperature change caused by the Earth's axial wobble impacted the availability of resources for early humans and our close cousins. The team combined the synthetic data generated by the 2ma simulation with the hard evidence of fossil and archaeological findings to find out where Homo sapiens and our genetic offspring were most likely to live.

The Pusan team noticed some surprising trends from the data. The researchers found that Homo heidelbergensis, thought to be the progenitors of both Neanderthals and modern humans, expanded from their traditional range around 700,000 years ago. They were able to do it because of the climate conditions at that time. The simulation projected the movement of these wet spots across the Earth and the researchers found evidence in the fossil record that moved along with them.

Timmermann told Nature that the global collection of skulls and tools is not random.

The single-evolutionary-path hypothesis postulates that climate change 700,000 years ago led to hotter, drier conditions in South Africa and eventually led to the rise of Homo sapiens.

We acknowledge that our species subdivisions may be controversial, but they don't necessarily need to have the same characteristics as other species.

The findings won't likely end the debate on humanity's beginnings, but they will add to our understanding.