Digest: Demographic changes and ancient introgression events might resolve Lewontin's Paradox in Australian geckos.

Abstract

Lewontin's Paradox concerns the weak correlation between genetic diversity and population size, challenging predictions of neutral theory. Lau et al. (2025) investigated this paradox in Gehyra geckos, finding a positive correlation between range size and heterozygosity. However, this relationship was not significant in the nana group, suggesting additional evolutionary forces are involved. Population expansion, local population dynamics, and ancient introgression likely contributed to shaping genetic diversity, highlighting the complexity of evolutionary processes beyond genetic drift.