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DEVELOPMENTAL NOISE, PHENOTYPIC PLASTICITY, AND ALLOZYME HETEROZYGOSITY IN DAPHNIA
Author(s) -
Yampolsky Lev Yu.,
Scheiner Samuel M.
Publication year - 1994
Publication title -
evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.84
H-Index - 199
eISSN - 1558-5646
pISSN - 0014-3820
DOI - 10.1111/j.1558-5646.1994.tb02207.x
Subject(s) - biology , loss of heterozygosity , phenotypic plasticity , evolutionary biology , daphnia , genetics , population , genetic variation , variation (astronomy) , allele , zoology , gene , demography , physics , crustacean , sociology , astrophysics
Previous theories and studies have postulated negative correlations between allozyme heterozygosity and developmental noise and between heterozygosity and phenotypic plasticity. We examined these relationships for morphological and life‐history traits of Daphnia magna in four independent experiments using two different Moscow populations and one German population. Clones were raised under a range of food levels or individual densities. Heterozygosity was scored at five allozyme loci in two experiments and at three loci in two others. Relative differences in developmental noise among clones with different heterozygosity levels were estimated as the pooled residual variation from an analysis of variation that removed the effects of macroenvironment, clones, and their interaction. Plasticity was measured as the amount of macroenvironmental variation plus genotype‐by‐environment interaction variation. We found a positive correlation between developmental noise and heterozygosity, although this correlation varied among traits and experiments. This result contradicts most previous claims about these relationships. In contrast, we found that phenotypic plasticity and heterozygosity were negatively correlated for some traits. Developmental noise and phenotypic plasticity were correlated for only two traits in two different experiments. This trait‐specific relationship is in concordance with previous studies. Our results could not be explained by effects of developmental time, a previously hypothesized mechanism. We propose several explanations for our results and the disparate results of others that do not require that heterozygosity be the actual cause of variation in developmental noise.