Homo erectus skull (oblique view) unrelated to study. Discovered in 1969 in Sangiran, Java, Indonesia. Dated to 1 million years ago. (© stockdevil - stock.adobe.com)
In a nutshell
- Scientists have discovered that Homo erectus adapted to extreme desert conditions in East Africa one million years ago, far earlier than previously thought possible for early humans
- These ancient humans demonstrated sophisticated survival strategies, repeatedly settling near river confluences and developing advanced tool-making skills, showing remarkable environmental awareness
- The findings challenge our understanding of early human capabilities, as Homo erectus survived for 1.5 million years, five times longer than our own species has existed so far
CALGARY — Scientists have made a remarkable discovery that’s changing what we thought we knew about our ancient relatives. At a site called Oldupai Gorge in Tanzania, researchers have found evidence that one of our early ancestors, Homo erectus, wasn’t just surviving but thriving in harsh desert-like conditions around one million years ago, much earlier than experts previously believed possible.
Until now, most scientists believed that only modern humans had the skills to live in extreme environments like deserts and rainforests. They thought our earlier relatives needed more welcoming habitats with ready access to water and food. This new research, published in Communications Earth & Environment, challenges that long-held belief.
“Now extinct, Homo erectus existed more than an estimated 1.5 million years, marking them as a species survival success in the human evolution story when compared with our own estimated existence of around 300,000 years to date,” explains Professor Michael Petraglia, Director of the Australian Research Centre for Human Evolution at Griffith University.
Professor Julio Mercader of the University of Calgary, the study’s lead author, attributes this success to their remarkable adaptability. “That success came down to their ability to survive over a long period marked by many changes to the environment and climate.”
The international research team, led by scientists from the University of Calgary and the University of Manitoba, conducted extensive studies at a site called Engaji Nanyori. Using multiple scientific techniques from analyzing ancient soils to studying fossilized plants and animals, they reconstructed what the environment looked like a million years ago. What they found was surprising: the landscape resembled today’s semi-deserts, with long dry periods and limited water availability.
The timing of this discovery is particularly important. These adaptations happened during what scientists call the Middle Pleistocene Transition, roughly 1.2 to 0.8 million years ago. It was a period of time marked by dramatic climate shifts. One can imagine the challenges of adapting to weather patterns becoming so increasingly unpredictable and extreme.
Who was Homo erectus?
Homo erectus, whose name means “upright human,” first appeared in Africa around 2 million years ago and represents a crucial milestone in human evolution. They were the first of our ancestors to have body proportions similar to modern humans, with longer legs and shorter arms compared to earlier species. Standing between 4.5 and 6 feet tall, they were also the first to show evidence of significant reduction in facial and tooth size, though their brains were still notably smaller than ours.
As pioneers of human migration, Homo erectus became the first of our ancestors to leave Africa, spreading into Asia and possibly southern Europe. They were also technological innovators, developing more sophisticated stone tools than their predecessors and likely being among the first to control fire – a crucial advancement that may have helped them adapt to various environments and cook food, leading to better nutrition.
This remarkably successful species survived for over 1.5 million years, far longer than our own species has existed, before going extinct around 110,000 years ago. During their long tenure on Earth, they shared the planet with several other human species, including the ancestors of both modern humans and Neanderthals, making them a central character in the story of human evolution.
“Debate has long centered on when the genus Homo acquired the adaptability to thrive in extreme environments,” said Dr. Abel Shikoni of the University of Dodoma in Tanzania. “Traditionally, only Homo sapiens was thought capable of sustained occupation in such ecosystems, with archaic hominins seen as restricted to narrower ranges.”
What’s especially clever about these ancient humans is how they chose their living spaces. The research shows they repeatedly settled near places where rivers met, making smart use of multiple water sources. It’s similar to how early modern cities often developed at river confluences. These ancient humans were using the same logic, just a million years earlier.
The evidence they left behind is substantial. Researchers found over 22,000 stone tools and 43,000 animal bones in an area about the size of three tennis courts. These aren’t just scattered remains. They show signs of skilled toolmaking and systematic butchering of animals, particularly medium-sized prehistoric cattle relatives.
Perhaps most fascinating is what the plant evidence reveals. The team found remains of drought-resistant shrubs called Ephedra, which today only grow thousands of kilometers north in the Sahara Desert. This suggests that desert-like conditions reached much farther south than anyone previously thought, showing just how harsh the environment was.
The research also found chemical signatures of frequent wildfires preserved in ancient soils, adding another challenge these early humans had to face. Despite these difficult conditions, the evidence shows they kept returning to the same areas over thousands of years.
This discovery fundamentally changes our understanding of human evolution. Homo erectus wasn’t just another species in our family tree. They were innovative survivors who could thrive in some of Earth’s most challenging environments. Their ability to adapt to such extreme conditions likely helped them become the first human species to spread across Africa and into Eurasia.
“The biogeochemical, palaeoenvironmental, and archaeological evidence we analysed suggests early Homo had the ability to adapt to diverse and unstable environments from the East African Rift floor and Afromontane areas as early as two million years ago,” Professor Petraglia said. “This adaptive profile, marked by resilience in arid zones, challenges assumptions about early hominin dispersal limits and positions Homo erectus as a versatile generalist and the first hominin to transcend environmental boundaries on a global scale.”
Paper Summary
Methodology
The researchers employed a comprehensive, multi-disciplinary approach. They analyzed sediment layers, dated rocks using advanced radiometric techniques, studied ancient pollen and plant remains, examined chemical signatures in the soil, and carefully documented thousands of stone tools and animal bones. They also used sophisticated climate modeling to reconstruct ancient weather patterns and environmental conditions. The team’s use of multiple, independent lines of evidence strengthens their conclusions about the environmental conditions and human activities at the site.
Results
The study found over 22,000 stone artifacts and 43,000 animal bone specimens across an area of more than 300 square meters. The stone tools showed evidence of sophisticated manufacturing techniques, while the animal bones displayed clear signs of butchery. Plant remains indicated an environment similar to modern semi-desert regions, with evidence of frequent fires. Dating techniques placed human occupation at approximately 990,000 years ago.
Limitations
While the evidence is substantial, the researchers acknowledge that the fossil record from this period is still relatively sparse. The study primarily focuses on one location, and while the findings are significant, more sites from this time period would help confirm how widespread these adaptations were among Homo erectus populations.
Discussion and Key Takeaways
This research fundamentally challenges previous assumptions about early human capabilities. It suggests that Homo erectus was far more adaptable than previously thought, capable of developing sophisticated survival strategies in harsh environments. This adaptability likely contributed to their success in spreading across Africa and into Eurasia.
Funding and Disclosures
The research was sponsored by the Canadian Social Sciences and Humanities Research Council under its Partnership Grant Program. The authors declared no competing interests.
Publication Information
This study was published in Communications Earth & Environment on January 16, 2025, titled “Homo erectus adapted to steppe-desert climate extremes one million years ago” by Julio Mercader, Pamela Akuku, and colleagues.
