García María B, Antor Ramón J
Instituto Pirenaico de Ecología (C.S.I.C.), Apdo. 64, 22700, Jaca (Huesca), Spain.
Oecologia. 1995 Jan;101(1):59-67. doi: 10.1007/BF00328901.
Sex ratio and sexual dimorphism of Borderea pyrenaica, a long-lived dioecious geophyte endemic to the Pyrenees (north-east Iberian Peninsula), were examined in three alpine populations. In this species, age can be estimated and the sex of nonreproductive adult plants identified. Male plants attain sexual maturity earlier, flower more frequently and grow faster than female plants, whereas females allocate a higher biomass to reproduction than males. These results support the hypothesis that female plants incur a higher cost of sexual reproduction and that this higher cost is measurable as reduced vegetative growth and lower flowering frequency. Variation of sex ratio among young, intermediate and old adults within populations suggests, however, that this higher female reproductive investment does not result in sexual differences in mortality. The overall male-biased sex ratio in B. pyrenaica is mainly a consequence of the tendency of males to reproduce at an earlier age and more frequently than females.
在比利牛斯山脉（伊比利亚半岛东北部）特有的一种长寿雌雄异株的地下芽植物比利牛斯博德瑞雅（Borderea pyrenaica）的三个高山种群中，研究了其性别比例和两性异形现象。在这个物种中，可以估算年龄并识别未生殖成年植株的性别。雄性植株比雌性植株更早达到性成熟，开花更频繁，生长更快，而雌性植株比雄性植株在繁殖上分配更高的生物量。这些结果支持了这样的假设，即雌性植株在有性生殖中付出更高的代价，并且这种更高的代价可通过营养生长减少和开花频率降低来衡量。然而，种群内年轻、中年和老年成年植株间性别比例的变化表明，这种更高的雌性生殖投入并不会导致死亡率上的性别差异。比利牛斯博德瑞雅总体上雄性偏多的性别比例主要是雄性比雌性倾向于更早且更频繁地进行繁殖的结果。
