Recently discovered human fossils from the Ledi-Geraru Research Project in a remote region of Ethiopia indicate an early presence of Homo around 2.78 million years ago and a previously unidentified species, Australian, dating back 2.63 million years.
Forensic facial reconstruction of Australopithecus afarensis. Image credit: Cicero Moraes/CC by-sa 3.0.
The timeline from approximately 3 to 2 million years ago represents crucial phases in human evolution.
This encompasses the genus Homo and Paran Solo Pass, which first appeared in fossil records alongside the ancestors of Australopithecus afarensis, a species that eventually vanished.
“We typically viewed human evolution as a linear trajectory from ape-like ancestors to modern humans. However, Homo sapiens researcher Brian Villmoare from the University of Nevada, Las Vegas, states that our understanding must adapt.”
“Humans have diversified into various niches multiple times throughout our history.”
“Our evolutionary tree reflects patterns not unique to us. Similar events occurred across different life forms.”
“This is something we should observe more frequently in the record of human fossils.”
“Nature has explored numerous paths toward humanity, particularly as climates became drier in East Africa, leading to the extinction of more ape-like species.”
Dr. Villmoare and his co-authors uncovered 13 human teeth at the Ledi-Geraru site in Ethiopia.
They determined that while some fossils belong to the genus Homo, others include upper and lower teeth sets from an unnamed species, Australian.
This new species differs from Australopithecus afarensis, which was first identified nearby at Khadar around 2.95 million years ago.
“The coexistence of both species in the same area suggests that human evolution resembles a branching tree rather than a linear progression,” said Dr. Villmoare.
The Ledi-Geraru site is also where paleontologists discovered the earliest jaw of Homo in 2013, dating back 2.8 million years.
“Recent findings of Homo teeth from sediments aged between 2 and 2.8 million years confirm the timeline of our lineage,” stated Dr. Villmoare.
“We know what the earliest teeth and jaws of Homo look like, but our findings extend beyond that.”
“This underscores the critical need for additional fossil discoveries to differentiate between Australian and Homo, and to explore potential overlaps in their fossil records.”
“There has been considerable geological activity in this region,” noted Dr. Christopher Campizzano, a geologist at Arizona State University.
“Numerous volcanic eruptions released ashes containing feldspar crystals, allowing scientists to date them.”
“We can date the eruptions that occurred in the landscape where these fossils were found.”
“These fossils are situated between volcanic deposits, facilitating age determination.”
“We are dating the volcanic ash from eruptions that coincided with the deposition of these fossils.”
“As this new research highlights, this was a pivotal era for human evolution,” said Professor Ramon Arrowsmith from Arizona State University.
“Geology provides critical insights into the age and characteristics of sedimentary layers, including those containing fossils.”
“Whenever an exciting new discovery occurs, paleontologists recognize that further information is essential,” commented Dr. Kay Reid, a paleontologist at Arizona State University.
“We need more fossils, which emphasizes the importance of training individuals to explore and identify new fossil sites.”
“The more fossils we uncover, the better we can understand our distant ancestors and the unique journey of survival that led to our existence.”
The findings are documented in a publication released today in the journal Nature.
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B. Billmoare et al. New discoveries of Australian and Homo from Ledi-Geraru, Ethiopia. Nature, published online August 13, 2025. doi:10.1038/s41586-025-09390-4
Source: www.sci.news
