First came the fossils. Pieced together, sketched and measured, the bones offered our first look at distant ancestors. But it was only a glimpse. Even with today’s highest resolution scans, researchers are limited to studying the structures and shapes they can see.
Then came the extraction and sequencing of ancient DNA (aDNA), which has advanced at a stunning pace. Genomes hundreds of thousands of years old can now be read, at least partially; aDNA has uncovered a new member of our family tree, the Denisovans, and revealed how our own species interbred with both them and Neanderthals.
But the genetic code is fragile and prone to microbial contamination and degradation over time. Researchers cap the potential for finding aDNA, even from an ideal site, at no more than a million years.
Ancient proteins, however, offer the molecular-level precision of aDNA with the sturdy longevity of a fossilized bone. They may be the key to unlocking the secrets of our past.
