Genetic studies Across North America: Total evidence approach - mitochondrial control region - lake comparisons- Lake Erie Structure
Phenotypic plasticity in Great Lakes yellow perch (Perca flavescens) as a result of the ontogenetic niche shift to piscivory
Aaron D. Parker, Donald G. Uzarski, Osvaldo J. Sepulveda-Villet, Carol A. Stepien, and Thomas M. Burton
Abstract: Morphological differentiation relating to ecological resources has been shown for many fishes inhabiting post-glacial ecosystems. However, information on the morphometrics of yellow perch (Perca flavescens) is sparse. Twenty-one morphological measurements and six meristic counts were made on 422 yellow perch collected in the nearshore zones of Lakes Huron and Michigan as well as from corresponding wetland/littoral zones in close proximity. Genetic variation was also assessed on a subset of fish using seven nuclear microsatellite loci. Principal components analysis suggested that the invertivorous/planktivorous yellow perch had proportionally larger paired fins and fewer, but longer, gill rakers. Piscivorous yellow perch had proportionally larger mouthparts and deeper bodies. The morphological differentiations appear to be related to feeding efficiency. Genetic comparisons showed no differences between subgroups of yellow perch within lakes, but significant divergences between Lakes Huron and Michigan. Because no genetic differences were observed among yellow perch sampling sites within lakes, our results indicate that the morphological differences are due to phenotypic plasticity.
Figure 1. Collection locations of yellow perch: Lake Michigan nearshore (♦), Lake Michigan drowned river mouth lake/river complexes (▲), Saginaw Bay nearshore (■), and Saginaw Bay wetlands (●).
Table 1. Genetic variation of yellow perch subgroups at seven microsatellite loci. NA = number of alleles, HO = observed heterozygosity, HE = expected heterozygosity, NA = mean number of alleles per individual sampled, NPA = number of private alleles, and PPA = proportion of private alleles within each subgroup. *=sample not in Hardy-Weinberg equilibrium after Bonferroni correction, N=presence of null alleles indicated.
Table 2. Pairwise FST values (Weir and Cockerham 1984) and associated p-values following sequential Bonferroni correction (Rice 1989) of yellow perch subgroups based on seven microsatellite loci (below diagonal) and four loci (above diagonal), excluding those with high non-equilibrium proportions. *=significant difference, NS=not significant.
Genetic studies Across North America: Total evidence approach - mitochondrial control region - lake comparisons- Lake Erie Structure
