Early self-replication may have started deep within rocks, like these white smokers
PHOTO: NOAA
At an unknown but momentous point in the origin of life on Earth, nucleic acids became the dominant self-replicating molecules. There's a problem, however, because normally, shorter nucleic acid polymers replicate faster than longer ones and outcompete them, with a subsequent loss of genetic information. Kreysing et al. studied DNA replication in a tiny pore with a thermal gradient across its width and a steady fluid flow along its length. In this confined space, perhaps similar to a pore within a rock, the longer nucleic acid chains outcompete their smaller brethren, which are diluted out of the pore.
Nat. Chem. 10.1038/nchem.2155 (2015).
