|SREL Reprint #0824|
Genetics of Mosquitofish.
Correlates, and Temporal and Spatial Heterogeneity of Allele Frequencies within
a River Drainage
W. Smith, Michael H. Smith and Ronald K. Chesser
populations within the Savannah River drainage were surveyed for biochemical
variation of proteins encoded by six loci.
Consistent excesses or deficiencies of heterozygotes were not observed
for any of the six loci, although strong spatial variation existed among
populations within and between creeks and reservoirs or within the river.
Heterozygosities of the river populations varied as function of the
distance from the first dam form the mouth of the river.
Two of six populations which had been sampled in a previous study several
years before this one showed significant changes in allele frequencies.
Differences in allele frequencies were related to major environmental
categories, such as water temperature, flow characteristics and elevation of the
site. These observations are not
consistent with the neutrality model but suggest a genetically dynamic species
subjected to both selection and stochastic processes as described in the
shifting balance model of evolution.
SREL Reprint #0824
Smith, M.W., M.H. Smith, and
R.K. Chesser. 1983.
Biochemical genetics of mosquitofish. I. Environmental
correlates, and temporal and spatial heterogeneity of allele
frequencies within a river drainage. Copeia 1983:182-193.