Bioinvasion Triggers Rapid Evolution of Life Histories in Freshwater Snails.

Bioinvasion Triggers Rapid Evolution of Life Histories in Freshwater Snails. Am Nat. 2017 Nov;190(5):694-706 Authors: Chapuis E, Lamy T, Pointier JP, Juillet N, Ségard A, Jarne P, David P Abstract Biological invasions offer interesting situations for observing how novel interactions between closely related, formerly allopatric species may trigger phenotypic evolution in situ. Assuming that successful invaders are usually filtered to be competitively dominant, invasive and native species may follow different trajectories. Natives may evolve traits that minimize the negative impact of competition, while trait shifts in invasives should mostly reflect expansion dynamics, through selection for colonization ability and transiently enhanced mutation load at the colonization front. These ideas were tested through a large-scale common-garden experiment measuring life-history traits in two closely related snail species, one invasive and one native, co-occurring in a network of freshwater ponds in Guadeloupe. We looked for evidence of recent evolution by comparing uninvaded or recently invaded sites with long-invaded ones. The native species adopted a life history favoring rapid population growth (i.e., increased fecundity, earlier reproduction, and increased juvenile survival) that may increase its prospects of coexistence with the more competitive invader. We discuss why these effects are more likely to result from genetic change than from ...
Source: The American Naturalist - Category: Biology Authors: Tags: Am Nat Source Type: research