Rhino Tooth from the Arctic Unlocks 20 Million Year Old Secrets

black rhino on field

Imagine holding a rhino tooth that’s over 20 million years old. Now imagine pulling ancient proteins from that tooth โ€” not just fragments, but full sequences that tell us about how rhinos evolved over tens of millions of years. Thatโ€™s exactly what a group of scientists just did, and itโ€™s kind of mind-blowing.

This ancient rhino tooth, found in Canadaโ€™s icy High Arctic, turned out to be a genetic time capsule. Researchers managed to recover enamel proteins so well-preserved that they could trace the animalโ€™s place in the rhino family tree โ€” way back during the Middle Eocene to the Oligocene era, between 41 to 25 million years ago. They also discovered that the two major rhino subfamilies โ€” Elasmotheriinae and Rhinocerotinae โ€” likely split later than we thought, maybe around 34โ€“22 million years ago.

The huge thing that had to be noticed about this is to push the limits of what we thought was possible. Ancient DNA usually doesnโ€™t survive more than a million years. But proteins? These enamel proteins survived 20 million. Thatโ€™s ten times further back in time than the oldest ancient DNA ever found. Wild, right?

The University of Yorkโ€™s team, including Dr. Marc Dickinson, helped confirm that these proteins werenโ€™t just random contamination or modern molecules sneaking into the fossil. They used something called chiral amino acid analysis โ€” basically, a test to check how much the amino acids had degraded over time and it was the real deal. โ€œItโ€™s phenomenal,โ€ said Dickinson. โ€œThese tools help us go deeper and ask new questions about ancient life.โ€

Credit: Nature

The high-latitude Haughton Crater on Devon Island has produced a highly endemic vertebrate fauna.

And thatโ€™s important. Rhinos today are endangered. Learning how they evolved and survived past environmental changes could help us understand what they need to survive now.

Until recently, scientists mainly relied on fossil shape or bits of DNA to piece together evolutionary histories. But DNA has its limits. Proteins, though! Scientists are now proving that proteins can survive much longer, especially when dental enamel locks them inside and permafrost keeps them preserved. Enamel acts like armor โ€” it protects whatโ€™s inside, even after millions of years.

Fazeelah Munir, a PhD researcher at York who helped analyze the tooth, said it best: โ€œThis gives a fresh perspective to scientists who already have incredible fossils sitting in collections. It shows we can learn so much more from them.โ€

And thereโ€™s something magical about where the fossil was found. According to Professor Enrico Cappellini from the University of Copenhagen, the Haughton Crater in the Arctic might be a kind of โ€œbiomolecular vaultโ€ โ€” a spot on Earth where conditions are just right to preserve delicate proteins over deep time.

So yeah, this isnโ€™t just about a rhino tooth. Itโ€™s a glimpse into a forgotten world โ€” and a reminder that even the tiniest traces of ancient life can tell incredible stories if we look closely enough.