The Bold and the Variable: Fish with High Heterozygosity Act Recklessly in the Vicinity of Predators

Abstract

Variation in the innate behavioral response to predation threat is often assumed to reflect genetic differences among the prey individuals. To date, no published results, however, exist that would offer explanation for the origin of this behavioral variation within populations. Using microsatellites as markers, we estimated the genetic variability of juvenile brown trout (Salmo trutta) individuals whose behavior had been individually recorded in a trade‐off situation where both predator chemical cues and food were present. Mean overall heterozygosity and the internal relatedness of fish associated significantly with their activity and foraging, so that the genetically more variable individuals showed more risk‐prone behavior under predation risk. No association between genetic variability and behavior was found in trials where predator odors were not present. These results were consistent over the three study populations of brown trout with different backgrounds, suggesting that the phenomenon is of general nature in this species. Of the possible mechanisms suggested to enable the existence of the positive association between neutral microsatellite variation and fitness‐related trait, the local effect hypothesis gained more support from our data than the general effect hypothesis.

Genetic variation in strains of zebrafish (Danio rerio) and the implications for ecotoxicology studies

“…Genetic variation has previously been shown to correlate with various measures of fitness (David 1998;Wang et al 2002) and influences individual behaviour (Tiira et al 2003;Vilhunen et al 2008). Susceptibility to toxicant pollution has also been shown to be significantly affected by genetic S TE TL TL TL TL TL TL TL TL TL TL TL TL TL TL TL TL TL TL TL TE TE TE TE TE TE TE TE TE TE TE TE TE TE TE AB variability; reduced levels being correlated with a lower tolerance to pollutants (Nowak et al 2007).…”

Condition‐dependent, phenotype‐dependent and genetic‐dependent factors in the natal dispersal of a solitary rodent

“…For example, for some non‐mammalian species, it has been observed that personality differences with regard to boldness in exploring novel habitats may affect dispersal (Dingemanse et al. 2003), and boldness can be related to genetic diversity (Vilhunen et al. 2008).…”

“…It is also possible that the exploration distance was not directly linked to heterozygosity either, but through some covariate trait. For example, for some non-mammalian species, it has been observed that personality differences with regard to boldness in exploring novel habitats may affect dispersal (Dingemanse et al 2003), and boldness can be related to genetic diversity (Vilhunen et al 2008). Risk-taking related behaviour is also linked to dispersal in American red squirrels, Tamiasciurus hudsonicus (Boon, Re´ale & Boutin 2008).…”

Behavioral mechanisms of trophic differentiation in benthivorous fish

“…The impact of predators may have evolutionary consequences (Portz and Harold, 2004;Walsh and Reznick, 2008;Smirnova and Gerasimov, 2010). Individual behavior plays an important role in the success of defensive activity (Lister and Neff, 2006;Vilhunen et al, 2008). Populations include the specimens able for more effi cient foraging in the presence of a predator minimiz ing at the same time the risk to be eaten.…”