Data from: Sexually antagonistic genetic variance for fitness in an ancestral and a novel environment

The intersex genetic correlation for fitness (rwfm), a standardized measure of the degree to which male and female fitness covary genetically, has consequences for important evolutionary processes, but few estimates are available and none have explored how it changes with environment. Using a half-sibling breeding design, we estimated the genetic (co)variance matrix (G) for male and female fitness, and the resulting rwfm,in Drosophila serrata. Our estimates were performed in two environments: the laboratory yeast food to which the population was well adapted and a novel corn food. The major axis of genetic variation for fitness in the two environments, accounting for 51.3 per cent of the total genetic variation, was significant and revealed a strong signal of sexual antagonism, loading negatively in both environments on males but positively on females. Consequently, estimates of rwfm were negative in both environments (-0.34 and -0.73, respectively), indicating that the majority of genetic variance segregating in this population has contrasting effects on male and female fitness. The possible strengthening of the negative rwfm in this novel environment may be a consequence of no history of selection for amelioration of sexual conflict. Additional studies from a diverse range of novel environments will be needed to determine the generality of this finding.

适合度的两性间遗传相关（intersex genetic correlation for fitness, rwfm）是衡量雌雄个体适合度在遗传层面共变异程度的标准化指标，其对诸多重要进化过程具有潜在影响，但目前相关估算数量极少，且尚无研究探讨该指标如何随环境变化而改变。本研究采用半同胞育种设计（half-sibling breeding design），对塞拉果蝇（Drosophila serrata）雌雄适合度的遗传（共）方差矩阵（G）及由此推导得到的rwfm值进行了估算。本次估算设置了两种实验环境：一是该种群已充分适应的实验室酵母培养基，二是新型玉米培养基。两种环境下，解释总遗传变异51.3%的适合度遗传变异主轴均具有统计学显著性，且呈现出强烈的性拮抗信号：在两种环境中，该主轴对雄性适合度的载荷均为负值，对雌性适合度的载荷则为正值。据此，两种环境下的rwfm估算值均为负值（分别为-0.34和-0.73），表明该种群中分离的绝大多数遗传变异对雌雄适合度具有截然相反的效应。新型环境下负向rwfm值的潜在增强，可能源于该种群未曾经历过用于缓解性冲突的选择压力。未来需开展涵盖更多不同新型环境的补充研究，方能明确该研究发现的普遍性。