Females of several catarrhine primate species exhibit exaggerated sexual swellings that change in size and coloration during the menstrual cycle and, in some species, gestation. Although their function remains under debate, studies indicate that swellings may contain information males could use to discern ovulation and the probability that a cycle will be conceptive. Here we combine visual ratings of swellings with hormonal data for a group of Sanje mangabeys (18 adult, 3 adolescent females) to determine if their swellings provide reliable information on female fertility. In all cases where ovulation was detected (N = 7), it occurred during maximum tumescence, and in 83.3% during the first two days of the “shiny phase,” a period during maximum tumescence when the swelling was brightest. There were no significant differences in maximum tumescence and shiny phase duration among cycles of different probability of conception, although there was a trend toward conceptive cycles exhibiting shorter shiny phases than nonconceptive ones. Only 25% (N = 4) of postconceptive swellings developed the shiny phase, and adolescents displayed the longest maximum tumescence and shiny phases. The conspicuous nature of the shiny phase and the frequent overlap between its onset and ovulation suggest that its presence serves as a general signal of ovulation and that the cycle has a high probability of being conceptive. It also suggests that swellings in some Sanje mangabeys are more accurate signals of fertility than in other primates.

中文翻译：

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野生桑吉曼加贝 (Cercocebus sanjei) 夸张的性肿胀和受孕概率

几种卡他灵长类动物的雌性表现出夸张的性肿胀，在月经周期和某些物种的妊娠期间，其大小和颜色会发生变化。尽管它们的功能仍然存在争议，但研究表明，肿胀可能包含男性可以用来辨别排卵和周期受孕概率的信息。在这里，我们将一组桑杰白眉猴（18 只成年白眉猴，3 只青春期雌性）的肿胀视觉评级与荷尔蒙数据结合起来，以确定它们的肿胀是否提供了有关女性生育能力的可靠信息。在所有检测到排卵的病例中 (N = 7)，排卵发生在最大肿胀期间，并且 83.3% 的排卵发生在“闪亮阶段”的前两天，即最大肿胀期间肿胀最亮的时期。不同受孕概率的周期之间，最大肿胀期和光泽期持续时间没有显着差异，尽管受孕周期有比非受孕周期表现出更短光泽期的趋势。只有 25% (N = 4) 的受孕后肿胀出现闪亮阶段，青少年表现出最长的最大肿胀和闪亮阶段。闪亮期的显着性质及其开始与排卵之间的频繁重叠表明，其存在可作为排卵的一般信号，并且该周期受孕的可能性很高。它还表明，与其他灵长类动物相比，一些桑杰白眉猴的肿胀是更准确的生育信号。