Boomsma J J, Grafen A
Department of Population Biology and Evolution, University of Utrecht, Utrecht, THE NETHERLANDS.
Department of Zoology, University of Oxford, Oxford, U.K.
Evolution. 1990 Jul;44(4):1026-1034. doi: 10.1111/j.1558-5646.1990.tb03823.x.
We consider worker-controlled sex investments in eusocial Hymenoptera (ants in particular) and assume that relatedness asymmetry is variable among colonies and that workers are able to assess the relatedness asymmetry in their own colony. We predict that such "assessing" workers should maximize their inclusive fitness by specializing in the production of the sex to which they are relatively most related, i.e., colonies whose workers have a relatedness asymmetry below the population average should specialize in males, whereas colonies whose workers have a higher than average relatedness asymmetry should specialize in making females. Our argument yields the expectation that colony sex ratios will be bimodally distributed in ant populations where relatedness asymmetry is variable owing to multiple mating, worker reproduction, and/or polygyny. No such bimodality is expected, however, in ant species where relatedness asymmetry is known to be constant, or in cases where relatedness asymmetry is supposed to be irrelevant due to allospecific brood rearing under queen control, as in the slave-making ants. Comparative data on colony sex ratios in ants are reviewed to test the predictions. The data partly support our contentions, but are as yet insufficient to be considered as decisive evidence.
我们考虑了群居性膜翅目昆虫（尤其是蚂蚁）中由工蚁控制的性别投资，并假设亲缘关系不对称在蚁群之间是可变的，且工蚁能够评估自身蚁群中的亲缘关系不对称情况。我们预测，这种“有评估能力”的工蚁应通过专门生产与其亲缘关系相对最密切的性别来最大化其广义适合度，即，工蚁的亲缘关系不对称低于种群平均水平的蚁群应专门生产雄性，而工蚁的亲缘关系不对称高于平均水平的蚁群应专门生产雌性。我们的观点得出这样的预期：在由于多次交配、工蚁繁殖和/或多雌多雄制导致亲缘关系不对称可变的蚂蚁种群中，蚁群的性别比例将呈双峰分布。然而，在已知亲缘关系不对称恒定不变的蚂蚁物种中，或者在由于蚁后控制下的异种育幼（如在奴役蚁中）而认为亲缘关系不对称无关紧要的情况下，预计不会出现这种双峰分布。我们回顾了关于蚂蚁蚁群性别比例的比较数据，以检验这些预测。数据部分支持了我们的观点，但目前还不足以被视为决定性证据。
