Meeting Abstract

88.5  Friday, Jan. 6  The genetic architecture of the bold-shy continuum in zebrafish, Danio rerio SINGER, M.L.*; OSWALD, M.E.; WIEDEBACK, B.D.; ROBISON, B.D.; Univ. of Idaho; Univ. of Notre Dame; Univ. of Idaho; Univ. of Idaho

Adaptation to captivity causes behavioral divergence among wild and captive populations. This divergence often occurs in a suite of traits related to the bold-shy continuum. The correlated evolution of these boldness behaviors may result from underlying genetic correlations, but the genetic architecture of the bold-shy continuum has seldom been studied. We used the Zebrafish (Danio rerio) to study the quantitative genetic architecture of the bold-shy continuum. We chose affinity to a human observer, depth preference, and feeding latency as our three behaviors associated with the bold-shy behavioral syndrome and found them all to be significantly correlated with each other. Using observer preference as a measure of “boldness,” we selectively bred “bold” and a “shy” lines. By the third generation, the lines had significantly diverged in all three of the behaviors measured. We used REML to estimate a G matrix for the three behaviors. All were significantly genetically correlated, and had narrow sense heritability estimates of 0.282 ±0.10 for observer preference, 0.207±0.11 for swim level, and 0.212±0.11 for feeding latency. Individuals from the third generation of the selection lines were subjected to an open field study assessing their behaviors when introduced to a novel environment. We found significant differences in time spent motionless, activity level, and cover usage according to their boldness scores. This study was conducted twice on two independently replicated selection lines, each producing results that were highly consistent with the other. The genetic architecture of the bold-shy continuum indicates that the behaviors stereotypical of domestic fishes may evolve because of genetic correlations.