Temporal genetic differentiation: continuous v. discontinuous spawning runs in anadromous rainbow smelt Osmerus mordax (Mitchill)

Genetic differentiation was greater between 'early' and 'late' spawning rainbow smelt Osmerus mordax separated by a hiatus in spawning activity compared to a continuously spawning population over a similar time period. This magnitude of temporal differentiation was comparable to that seen among spatially separated populations.