According to a study published in the Nature Communications Earth & Environment journal, an early human ancestor of our species navigated more successfully in harsher and more arid terrains for longer in East Africa than previously thought.
Homo erectus, the oldest living relative of our species to have body proportions similar to humans and the first known human ancestor to migrate out of Africa, was the focus of the new study conducted by an international research team.
The researchers analyzed evidence from Engaji Nanyori in the Oldupai Gorge, Tanzania, revealing that Homo erectus prospered in hyper-arid landscapes one million years ago – long before the appearance of our species, Homo sapiens.
“Currently extinct, Homo erectus existed for more than 1.5 million years, which makes it a success story in the history of human evolution, when compared with our own existence, estimated at about 300,000 years to date,” says Professor Michael Petraglia, Director of Griffith University’s Australian Research Centre for Human Evolution.
“That success was due to its ability to survive during a long period marked by many environmental and climate changes,” notes lead author Professor Julio Mercader of the University of Calgary.
Using biogeochemical analyses, chronometric dating, paleoclimatic simulations, biome modeling, reconstructions of fire history, paleobotanical studies, faunal assemblages, and archaeological evidence, a equipa de investigação reconstruiu um ambiente dominado por arbustos semidesérticos.
Despite the challenges of these conditions, Homo erectus repeatedly occupied landscapes shaped by rivers and streams, taking advantage of water sources and ecological focal points to mitigate risks.
These findings suggest that archaic humans possessed ecological flexibility previously attributed only to later hominins.
“For a long time, the debate has centered on the question of when the Homo genus acquired the adaptability to thrive in extreme environments, such as deserts and tropical forests,” says Abel Shikoni of the University of Dodoma in Tanzania.
“Traditionally, it was thought that only Homo sapiens was capable of sustainably occupying these ecosystems, with archaic hominins seen as limited to more restricted areas,” he adds.
Nevertheless, he explains, “the biogeochemical, paleoenvironmental and archaeological evidence we analyzed suggests that the primitive Homo had the capacity to adapt to diverse and unstable environments at the bottom of the East African Rift and in Afro-montane zones two million years ago,” says Professor Petraglia.
“This adaptive profile, marked by resilience in arid zones, probably challenges the assumptions about the dispersal limits of early hominins and positions the Homo erectus as a versatile generalist and the first hominin to transcend environmental boundaries on a global scale,” reveals the lecturer.
“This adaptability likely facilitated the expansion of Homo erectus into the arid regions of Africa and Eurasia, redefining its role as ecological generalists who thrived in some of the most challenging landscapes of the Middle Pleistocene,” concludes Professor Paul Durkin of the University of Manitoba.
