Definition
Plain language
Traits disappearing from a population by sheer luck rather than because they were worse.
As stated in the literature
Random change in variant frequencies due to finite sampling; invoked as an analogy for retrieval loops where the surviving answer is determined by which entities happened to cross an amplification threshold first, not by correctness.
Why it matters: It is a reminder that what survives in a system isn't always what's best — sometimes it's just what got lucky early, which is how a wrong answer can win a retrieval loop.
For example, in a small isolated population a harmless eye color can vanish entirely just because the few individuals who carried it happened to have no children.