2.65 million-year-old fossil teeth unearthed in Ethiopia opens up current understandings of human evolution
The team of scientists found a total of 10 teeth — six molars, two incisors, one premolar and one canine — they believe came from two members of the new Australopithecus species, which hasn't yet been named.
Scientists found 10 teeth they determined belonged to a new Australopithecus species.
via REUTERS
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The new species marks the seventh discovered genus of Australopithecus, an early ancestor of today's people, primarily ape-like in appearance but with human characteristics like bipedal walking. Australopithecus also had dental features almost identical to modern-day people, including a complete set of 32 teeth.
The team also unearthed three other teeth that are roughly 2.59 million years old with traits consistent among the oldest-known Homo species first identified in 2013, which hasn't been formally named either.
Both species haven't been assigned official names because the collected fossils are still incomplete.
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Still, the fossils provide much-needed insight into a relatively murky era of human evolution, as the close age of the teeth indicates the two unnamed species could've coexisted — or even competed for resources.
The teeth also confirm that there were at least four types of hominins throughout East Africa at the time, with a fifth roaming in southern Africa.
'This reinforces the idea that the story of human evolution is not of a single lineage changing slowly through time,' Brian Villmoare, University of Nevada, Las Vegas paleoanthropologist and lead author of the research published on Wednesday in the journal Nature, said.
The team also found more teeth linked to a separate Homo species first identified in 2013.
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'Rather, the pattern of human evolution is similar to that of other organisms, repeatedly branching into multiple species throughout the fossil record, many of whom lived at the same time.'
Researchers plan on analyzing the fossils to see if the unnamed species shared similar foods or had any notable interactions.
Humans, or Homo Sapiens, are the youngest member of the Homo genus, having only originated roughly 300,000 years ago in Africa.
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The Homo genus is generally believed to have descended from a species of Australopithecus before it eventually died out. The exact species of Australopithecus, though, is hotly contested.
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