Scientists have identified a mysterious 3.4-million-year-old fossil foot found in Ethiopia as belonging to a previously known early human species that lived at the same time and in the same region as “Lucy,” revealing that more than one human ancestor shared the East African landscape and walked upright in different ways.
According to new findings published in the journal Nature and reported by ScienceDaily, researchers have confirmed that the fossil, first discovered in 2009 in Ethiopia’s Woranso-Mille area, matches Australopithecus deyiremeda, a species formally announced in 2015. This establishes that Lucy’s species (Australopithecus afarensis) was not the only hominin thriving in the region about 3.4 million years ago. Scientists say this discovery reshapes our understanding of early human evolution, showing that multiple species were experimenting with different lifestyles rather than following a single evolutionary path.
The fossil, often referred to as the Burtele foot, stood out because its big toe was opposable — more suitable for climbing than the fully aligned big toe seen in Lucy’s species. Researchers say the species likely walked on two legs on the ground but retained a strong ability to grasp branches, suggesting a dual life between forests and open terrain.
Further laboratory analysis of tooth enamel from the region revealed clear dietary differences. While Lucy’s species consumed a mix of woodland and grassland foods, A. deyiremeda relied more heavily on tree-based resources such as fruits and leaves. Scientists believe these unique dietary habits helped the species coexist without competing directly for food.
The team also used CT-scanning to examine a juvenile jaw and developing teeth from the same area, strengthening the connection between the fossils and offering insight into the growth patterns of the species. The presence of multiple hominin species living side by side suggests that natural selection was testing several evolutionary routes at once, each adapting differently to a changing environment.
Researchers say these discoveries from Ethiopia’s Afar Rift are not just about filling gaps in the human family tree — they may also reveal how ancient species survived shifts in climate and habitat. Understanding those patterns, they add, could help scientists today as the modern world faces rapid environmental change.
The study, led by a multinational team from the United States and other institutions, highlights that our origins are far more complex than once believed. Even millions of years ago, our ancestors were exploring different ways to walk, eat, move and survive — long before modern humans evolved.
