Meeting Abstract

P3.64  Monday, Jan. 6 15:30  Individual (co)variation in standard metabolic rate, feeding rate, and exploratory behavior in semi-aquatic salamanders GIFFORD, M/E*; CAREAU, V; CLAY, T/A; Univ. of Arkansas, Little Rock; Deakin University, Victoria, Australia; Univ. of Arkansas, Little Rock megifford@ualr.edu

Repeatability is an important measurement in evolutionary analyses because it provides information regarding the benefit of repeated measurements and a putative upper limit to heritability estimates. Repeatability of different aspects of energy metabolism and behavior have been demonstrated in a variety of organisms over short and long time intervals. Recent research suggests that consistent individual differences in behavior and energy metabolism might covary. We present data on the repeatability of body mass, standard metabolic rate (SMR), voluntary exploratory behavior, and feeding rate in a semi-aquatic salamander, Desmognathus brimleyorum, and ask whether individual variation in behavioral traits are correlated with individual variation in SMR on a whole-animal and mass-residual basis. All measured traits were repeatable, but repeatability estimates ranged from very high for body mass (r=0.98), intermediate for SMR (r=0.39) and food intake (r=0.58), to low for exploratory behavior (r=0.25). In addition, repeatability estimates for all traits except body mass declined over time (i.e., from 3 to 9 weeks). Despite significant repeatability in all traits, we find little evidence that behaviors are correlated with SMR at the phenotypic or among-individual levels on a mass-residual basis. The phenotypic correlations between SMR and exploratory behavior were negative in all trials, but significantly so in one trial only. Salamanders in this study exhibited individual variation in how their exploratory behavior changed across trials (but not body mass, SMR, and food intake), which might have contributed to observed changes in correlations across trials.