Scientists Found a 24-Million-Year-Old Rhino Tooth. Here’s Why That’s a Really Big Deal.

A team of scientists from the University of Copenhagen says they’ve recovered ancient proteins from a 24-million-year-old rhinoceros tooth dug out of the frozen wilds of the Canadian Arctic. These proteins are ten times older than the oldest DNA ever sequenced.

The team, led by researchers Ryan Paterson and Enrico Cappellini, owes its discovery to the toughness of tooth enamel. It is so sturdy that it can hold onto proteins for millions of years like a little molecular time capsule.

The rhino in question was pulled from Nunavut’s icy Haughton Formation, and it’s going to help scientists figure out where its particular breed falls in the rhino family tree. So far, they suspected somewhere between a woolly rhino and the Siberian unicorn.

Before we go on: yes, there was a creature called a unicorn, but it had nothing to do with the magical Lisa Frank-looking white horse we associate with the word. It was a hairy rhino with a gigantic horn.

24-Million-Year-Old Rhino Tooth Is a Biological ‘Game-Changer’

In Kenya’s Turkana Basin, a second team led by scientists from the Smithsonian and Harvard also discovered ancient proteins, this time in fossils up to 18 million years old.

What makes this discovery particularly noteworthy is that these molecules were preserved in the blazing heat of a tropical desert, upending the assumption that proteins can only survive in deep-freeze conditions.

Consider all of this your first introduction to a whole new potential field of research called paleoproteomics, defined in a 2022 research paper as “the study of ancient proteins.” This field is going to help fill in the gigantic chronological blind spots left by DNA, which tends to fade away after 1 million years.

Proteins, on the other hand, are tougher, more persistent, and are still capable of telling the story of the creature they lived in after all these millennia.