Maintenance of phenotypic variation: repeatability, heritability and size-dependent processes in a wild brook trout population.

ABSTRACT: Phenotypic variation in body size can result from within-cohort variation in birth dates, among-individual growth variation and size-selective processes. We explore the relative effects of these processes on the maintenance of wide observed body size variation in stream-dwelling brook trout (Salvelinus fontinalis). Based on the analyses of multiple recaptures of individual fish, it appears that size distributions are largely determined by the maintenance of early size variation. We found no evidence for size-dependent compensatory growth (which would reduce size variation) and found no indication that size-dependent survival substantially influenced body size distributions. Depensatory growth (faster growth by larger individuals) reinforced early size variation, but was relatively strong o

SUBMITTER: Letcher BH 

PROVIDER: S-EPMC3352425 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature