The variance of response to selection in Tribolium castaneum

Abstract

Selection for higher pupa weight in Tribolium castaneum was practised over three generations on six sets of three replications comprised of 10 families each. A check on a prediction of the variance of response to selection between replicates over generations showed that this predictor underestimated the actual variance in 13 out of 18 cases. In addition, there was a significant Spearman's rank correlation (r = 1) between the absolute value of the kurtosis of the base population and the mean standardized difference between the predicted and measured variances within sets. Taking account of the sampling variance of realized heritabilities across generations, as well as the additional variance owing to linkage disequilibrium, did not improve the fit of the predictor.