Nairobi – In what may be one of the most groundbreaking scientific discoveries of the decade, researchers from Harvard and the University of Copenhagen have extracted and sequenced the oldest known protein from a fossil—estimated to be 24 million years old. The protein, retrieved from the enamel of an extinct rhinoceros tooth found in Kenya, is now rewriting what scientists believed was possible in the field of evolutionary biology.
Until now, the oldest DNA sample ever recovered dated back only 2 million years. But proteins, which are fundamental components of DNA, have proven to be far more durable. This makes them an invaluable molecular key for unlocking the genetic history of lifeforms far beyond the preservation limits of DNA.
The discovery, published in Nature, comes from a dual excavation project conducted in two vastly different climates—one in the Arctic-bordering regions of Canada and the other in Kenya’s Great Rift Valley. The fossil samples include teeth from now-extinct rhinos, elephants, and hippopotamuses, ranging from 1.5 to 24 million years old.
“This complementary project shows that proteins, the molecular archive of evolutionary history, can be preserved and retrieved across radically different environments,” said Daniel Green, evolutionary biologist at Harvard University.
Scientists isolated peptides—short chains of amino acids—from tooth enamel, the hardest and most resilient biological structure. The ability to retrieve genetic information from these peptides allows researchers to track evolutionary relationships, determine sex, and potentially reconstruct the phylogenetic tree with greater clarity.
The implications are vast. Ryan Sinclair Paterson from the University of Copenhagen explained, “Ancient proteins provide molecular data from specimens far too old for DNA preservation. It opens a powerful new window into the lineage of extinct species—and possibly into our own ancestry.”
The Kenyan fossil samples not only align with the migration patterns of prehistoric mammals but also hint at the region’s significance in human origins. Timothy Cleland of the Smithsonian Institution noted that the findings may offer critical insights into early Hominin evolution within East Africa.
Intriguingly, the study suggests this technology could reach even deeper into history. “We now believe paleoproteomics can be extended into the Mesozoic era,” said Green, referring to the age of the dinosaurs that ended 66 million years ago.
This revelation is sending ripples across the global scientific community. What began with the fossilized tooth of a long-extinct rhinoceros could soon upend our understanding of life’s timeline—and human origins.
