Life’s origin has long hinged on a chicken-and-egg riddle: proteins do nearly everything in cells, but ribosomes make proteins using RNA instructions. A new Nature study offers a concrete first move in that dance, showing that under simple, early-Earth-like conditions, amino acids can attach to RNA in water and begin forming the peptide links that underpin proteins, no ribosome required.⁠ ⁠ The team at University College London activated amino acids as thioesters using pantetheine, a sulfur-bearing molecule tied to modern metabolism. Those activated amino acids spontaneously and selectively transferred onto strands of RNA at neutral pH, creating aminoacyl-RNA and then short peptide bonds. In doing so, the chemistry unites two classic origin-of-life ideas: an “RNA world,” where RNA stores and processes information, and a “thioester world,” where high-energy thioesters power fledgling metabolism.⁠ ⁠ Crucially, this works in plain water and likely in places where small ponds or lakes coul...