RT Journal Article
SR Electronic
T1 Artificial selection on male size depletes genetic variance but not covariance of life history traits in the yellow dung fly
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 664326
DO 10.1101/664326
A1 WU Blanckenhorn
A1 V Llaurens
A1 C Reim
A1 Y Teuschl
A1 E Postma
YR 2019
UL http://biorxiv.org/content/early/2019/06/10/664326.abstract
AB The evolutionary potential of organisms depends on the presence of sufficient genetic variation for traits subject to selection, as well as on the genetic covariances among them. While genetic variation ultimately derives from mutation, theory predicts the depletion of genetic (co)variation under consistent directional or stabilizing selection in natural populations. We estimated and compared additive genetic (co)variances for several standard life history traits, including some for which this has never been assessed, before and after 24 generations of artificial selection on male size in the yellow dung fly Scathophaga stercoraria (Diptera: Scathophagidae) using a series of standard half-sib breeding experiments. As predicted, genetic variances (VA), heritabilities (h2) and evolvabilities (IA) of body size, development time, first clutch size, and female age at first clutch were lower after selection. As independent selection lines were crossed prior to testing, we can rule out that this reduction is due to genetic drift. In contrast to the variances, and against expectation, the additive genetic correlations between the sexes for development time and body size remained strong and positive (rA = 0.8–0.9), while the genetic correlation between these traits within the sexes tended to strengthen (but not significantly so). Our study documents that the effect of selection on genetic variance is predictable, whereas that on genetic correlations is not.