Fossilized tooth present in Ethiopia elevate questions on established timeline of Australopithecus

Arizona State University researchers unearthed fossils in Ethiopia that will have belonged to a beforehand undiscovered species of human ancestor.

The researchers say they discovered 2.6 million-year-old fossilized tooth from an offshoot of an extinct group of primates known as Australopithecus. And they are saying it’s attainable the tooth belong to a brand new species, due to their form and after they seem within the fossil file.

“Lucy, her species’ last evidence for her, is around 3 million years or so,” mentioned Christopher Campisano, ASU geologist and research co-author. “And then we pick up this new material around, say, 2.7 million years.”

Lucy is notable for being the most-complete fossilized skeleton ever discovered that derived from the species Australopithecus afarensis.

The specimens discovered on this most up-to-date paper have been collected between 2015 and 2018 as part of the Ledi-Geraru analysis challenge.

ASU researchers say the newest fossils have been additionally discovered to exist across the identical time as a number of the first homo species, relationship from 2.78 and a couple of.59 million years in the past. Homo is the genus of primates that people — homo sapiens — belong to.

The staff says it’s too quickly to verify if these Australopithecus tooth really belong to a brand new species, however there are some indicators.

“When you compare it to a suite of other known material from known taxa, it sort of falls, you know, either outside of the range of variation or on the edges of range of variation of what we know,” Campisano mentioned. “And so, in the paper, we put up a couple different hypotheses that — or probabilities that — this could represent.”

The staff was capable of date the fossils by analyzing volcanic-ash minerals known as feldspar, which might have crystallized on the time of the eruption.

“They contain potassium that radioactively decays to argon, and we can use that decay method … to then date those feldspars,” Campisano mentioned. “So what we’re essentially dating is multiple units of volcanic ashes in these sequences, and the fossils are in a bed with those volcanic-ash sequences.”

The analysis staff consists of a mixture of specialists from completely different fields, together with paleontologists and geologists like Campisano.

“We have people specific to the dating, whether it’s argon dating or paleomagnetic dating, and so it is a huge, multidisciplinary project,” he mentioned. “Again, this is very common in paleontology and archaeology and other disciplines, as well. And so we all sort of have our little role to do, basically, and we all work together.”

For Campisano, learning the lineage of human evolution is about greater than scientific discovery.

“These sorts of projects sort of put you in touch with your humanity and show us that we all sort of have this common ancestry,” Campisano mentioned. “Whatever is happening in the world, you know, you can go out on these landscapes and hike around and find the origins of all of this.”

The research was revealed within the journal Nature.