It’s the ultimate chicken-and-egg conundrum. Life doesn’t work without tiny molecular machines called ribosomes, whose job is to translate genes into proteins. But ribosomes themselves are made of proteins. So how did the first life arise?
Researchers may have taken the first step toward solving this mystery. They’ve shown that RNA molecules can grow short proteins called peptides all by themselves—no ribosome required. What’s more, this chemistry works under conditions likely present on early Earth.