Hoffman Christy L, Ruiz-Lambides Angelina V, Davila Edgar, Maldonado Elizabeth, Gerald Melissa S, Maestripieri Dario
Department of Comparative Human Development, The University of Chicago, Chicago, IL 60637, USA.
Behav Ecol Sociobiol. 2008 Sep;62(11):1711-1718. doi: 10.1007/s00265-008-0599-z.
In sexually promiscuous mammals, female reproductive effort is mainly expressed through gestation, lactation, and maternal care, whereas male reproductive effort is mainly manifested as mating effort. In this study, we investigated whether reproduction has significant survival costs for a seasonally breeding, sexually promiscuous species, the rhesus macaque, and whether these costs occur at different times of the year for females and males, namely in the birth and the mating season, respectively. The study was conducted with the rhesus macaque population on Cayo Santiago, Puerto Rico. Data on 7,402 births and 922 deaths over a 45-year period were analyzed. Births were concentrated between November and April, while conceptions occurred between May and October. As predicted, female mortality probability peaked in the birth season whereas male mortality probability peaked in the mating season. Furthermore, as the onset of the birth season gradually shifted over the years in relation to climatic changes, there was a concomitant shift in the seasonal peaks of male and female mortality. Taken together, our findings provide the first evidence of sex differences in the survival costs of reproduction in nonhuman primates and suggest that reproduction has significant fitness costs even in environments with abundant food and absence of predation.
在性滥交的哺乳动物中，雌性的繁殖投入主要通过妊娠、哺乳和母性照料来体现，而雄性的繁殖投入主要表现为交配投入。在本研究中，我们调查了对于一种季节性繁殖、性滥交的物种——恒河猴而言，繁殖是否具有显著的生存成本，以及这些成本对于雌性和雄性是否在一年中的不同时间出现，即分别在生育季节和交配季节出现。该研究是在波多黎各圣地亚哥岛的恒河猴种群中进行的。分析了45年间7402次出生和922次死亡的数据。出生集中在11月至4月之间，而受孕发生在5月至10月之间。正如预测的那样，雌性死亡概率在生育季节达到峰值，而雄性死亡概率在交配季节达到峰值。此外，随着生育季节的开始年份与气候变化相关逐渐发生变化，雄性和雌性死亡率的季节性峰值也随之发生了相应的变化。综上所述，我们的研究结果首次证明了非人类灵长类动物在繁殖生存成本上存在性别差异，并表明即使在食物丰富且没有捕食的环境中，繁殖也具有显著的适合度成本。
