Science

Ancient tooth proteins reveal our relation to mysterious human species

Ancient tooth proteins reveal ...
A digital recreation of one of the main samples of Homo antecessor, which has now been placed on the family tree thanks to studies of ancient proteins in its teeth
A digital recreation of one of the main samples of Homo antecessor, which has now been placed on the family tree thanks to studies of ancient proteins in its teeth
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A digital recreation of one of the main samples of Homo antecessor, which has now been placed on the family tree thanks to studies of ancient proteins in its teeth
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A digital recreation of one of the main samples of Homo antecessor, which has now been placed on the family tree thanks to studies of ancient proteins in its teeth
The remains of Homo antecessor
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The remains of Homo antecessor
A tooth from Homo antecessor was studied using palaeoproteomics
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A tooth from Homo antecessor was studied using palaeoproteomics
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It’s hard to piece together the full history of human evolution from piles of old bones. But now, scientists have made use of a new method to study proteins in dental enamel of an 800,000-year-old human species, helping place it in the family tree.

Although Homo sapiens is the only human species still alive today, the road to get here is paved with extinct relatives. And untangling how they’re all related to each other is a task that scientists continue to wrestle with. The timeline is usually determined through various dating processes, both on the bones themselves and the sediment layers they’re found in. Relationships between species are then determined from this timeline, and by examining the structures and features of the bones to track the progress of evolution.

For the new study, researchers at the University of Copenhagen have used a new tool called palaeoproteomics to get a more precise picture. This involves sequencing proteins from ancient remains, and it works on samples that are far too old to have intact DNA. In this case, the team applied it to the 800,000-year-old teeth of a mysterious, archaic human species called Homo antecessor.

The remains of Homo antecessor
The remains of Homo antecessor

“Using state of the art mass spectrometry, we determine the sequence of amino acids within protein remains from Homo antecessor dental enamel,” says Jesper Velgaard Olsen, co-author of the study. “We can then compare the ancient protein sequences we ‘read’ to those of other hominins, for example Neanderthals and Homo sapiens, to determine how they are genetically related.”

With this process, the team managed to pin down Homo antecessor’s place in the family tree with greater precision than ever before. It had previously been put forward that this species was the last common ancestor for us modern humans, Neanderthals, and Denisovans. But the new study suggests that while we are closely related, we aren’t directly derived from Homo antecessor – it was less of a great grandfather and more of a great uncle.

“Ancient protein analysis provides evidence for a close relationship between Homo antecessor, us (Homo sapiens), Neanderthals, and Denisovans,” says Frido Welker, first author on the study. “Our results support the idea that Homo antecessor was a sister group to the group containing Homo sapiens, Neanderthals, and Denisovans.”

The team says that applying palaeoproteomics to other fossils could reveal other new details about human ancestors. We doubt the family tree has seen its last revision.

The research was published in the journal Nature.

Source: University of Copenhagen

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7 comments
Loc
There has never been anything but jumbled bones and wild guess's to support the theory of evolution.
alexD
Loc, that is true but it's a very good approximation and until we develop that fabled time machine, guesses is all we will have
Shabkar
Why would anybody who doesn't believe in evolution read a science and tech publication? But you're right, why would I believe in evolution when I could believe in an invisible supernatural male human who makes universes and micromanages them?
Tony Morris
Loc, that is nonsense. Every new piece of evidence totally supports the theory of evolution and helps unravel what is an amazingly complex puzzle. Young earth creationism has no explanation for the amazing diversity of hominid species that no longer exist. Hint - there are no homo sapiens in the fossil record dating this far back - or even close. . . . and this creature wasn't even our ancestor, it was on a different branch.
Worzel
@Loc The theory of evolution, is just that, a 'THEORY'! ie, A working rule of thumb, that is used until something better arrives. If the ''Cambrian Explosion'' is considered, the 'slow changes over time' is probably only one facet of how life evolved. Given the fragility of most primate bones, and how easily they decay in the wrong conditions, it's amazing that so much has been discovered/uncovered. With time, and improvements in science technology, it may be that the hominid family tree will be infinitely more extensive than even that discovered so far. The real question tho' is, why are they not still around?
holdenmidfield
Loc, that pile of bones must be in your own bonehead.
BeatleMacca
Loc, It looks like you stirred up the evolution ant bed. Made me smile.