Appraisal of the consequences of the DDT-induced bottleneck on the level and distribution of neutral genetic variation in Canadian peregrine falcons, Falco peregrinus.

摘要

Peregrine falcons (Falco peregrinus) underwent severe population declines in the 20th century due to chlorinated hydrocarbon contamination. The present study assesses the consequences of this decline on the level and distribution of neutral genetic variation within and between Canadian populations of the North American subspecies ( F. p. anatum, F. p. tundrius, and F. p. pealei).; Genetic diversity was low for all populations in both time periods. The mitochondrial control region in particular exhibited extremely low polymorphism, with a total of five haplotypes range-wide. Despite theoretical and empirical expectations, neither significant declines in genetic diversity nor consistent bottleneck signatures were found for any subspecies. In fact, contemporary levels of diversity are generally higher than historical levels. Distorted conclusions would have been reached had museum specimens not been included. The lack of a bottleneck signature is rationalized by the promptness of the recovery and the possible introgression of alleles from non-native individuals.; In terms of population genetic structuring, only two diagnosable genetic groups were identified in historical samples: pealei, and all other individuals. These results indicate that tundrius has no genetic basis, and so should be subsumed into anatum. (Abstract shortened by UMI.)