Repeatability and Heritability of Behavioural Types in a Social Cichlid

Abstract

Aim. The quantitative genetics underlying correlated behavioural traits (‘‘animal personality”) have hitherto been studied mainly in domesticated animals. Here we report the repeatability (R) and heritability (h2) of behavioural types in the highly social cichlid fish Neolamprologus pulcher. Methods. We tested 1779 individuals repeatedly and calculated the h2 of behavioural types by variance components estimation (GLMM REML), using 1327 offspring from 162 broods from 74 pairs. Results. Repeatability of behavioural types was significant and considerable (0.546), but declined from 0.83 between tests conducted on the same day, to 0.19 on tests conducted up to 1201 days apart. All h2 estimates were significant but low (e.g., pair identity h2 = 0.15 ± 0.03 SE). Additionally, we found significant variation between broods nested within the parent(s), but these were not related to several environmental factors tested. Conclusions. We conclude that despite a considerable R, h2 in this cichlid species is low, and variability in behavioural type appears to be strongly affected by other (non)genetic effects.

Coloration reflects behavioural types in the convict cichlid, Amatitlania siquia

“…The fish only rarely consumed the slice of macaroni pasta in the test for food neophobia, so we were unable to test repeatability of this behavioural response. However, the behavioural response to novelty is known to be consistent over time in cichlids (Chervet, Z€ ottl, Schürch, Taborsky, & Heg, 2011;Jones & Godin, 2010). Thus, food neophobia was used in subsequent analyses focusing solely on the time needed to consume krill.…”

Subjective evaluation of defensive behavior in the Syrian honeybee (Apis mellifera syriaca)

“…In general, it should be noted that repeatability estimates differ greatly according to the nature of the characteristics (Bell et al, 2009) and to the genetic properties of the population and the environmental conditions under which the individuals are kept (Falconer and Mackay, 1996;Van Dongen et al, 2010). Thus, it is not surprising that multiple studies estimate very different repeatability levels for the same character among and within species (Chervet et al, 2011). In reality, it is impossible to remove all subjectivity from the assessment of behavior or temperament because all methods depend on human perception.…”

Rescuing the baby from the bathwater: a reply to Carter (2013)

“…Indeed, this is a common procedure in animal personality research [3]. However, this procedure raises other methodological problems that are seldom discussed and that have to do with the need to control for variation in the valence and salience of the NOs used and their functional value to the…”

“…In our view, only the measurement of within-context consistency could clarify the point raised by the author, which unfortunately was not measured in the original study [2], based on the assumption of NO tests having high repeatability. This assumption was based on the wide use of the NO test in animal personality research and on available data for other cichlid species [3] that suggests a high within-context consistency of NO test measures in the short-term for this taxon. Thus, it is this assumption (and not the lack of between context consistency) that should be questioned, and in this regard we second Carter's view that within-context consistency should always be verified in animal personality studies.…”