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Updated: Mar 1, 2026

Examination of Host Phenotypes in Gambusia affinis Following Antibiotic Treatment
Published on: February 22, 2017
SINGLE- AND MULTIPLE-LOCUS GENOTYPES AND LIFE-HISTORY RESPONSES OF GAMBUSIA HOLBROOKI REARED AT TWO TEMPERATURES
Margaret Mulvey1, Gwen P Keller1, Gary K Meffe1
1University of Georgia, Savannah River Ecology Laboratory, Drawer E, Aiken, South Carolina, 29802.
Abstract:
Eastern mosquitofish (Gambusia holbrooki) were reared from birth to 10 wk of age at 25°C and 32°C. Relationships of growth, time to maturity, and developmental stability to isozyme genotype were used to examine the hypothesis that more heterozygous individuals should exhibit superior performances, especially under thermally stressful (32°C) conditions. More heterozygous fish grew faster than homozygous individuals, especially at 32°C. Significant differences in time to maturity were detected among allozyme genotypes but not with heterozygosity. Multiple-locus heterozygosity was negatively related to fluctuating asymmetry. Thus, life-history traits were affected by both multiple-locus heterozygosity and single-locus genotype.
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