Female sexual swelling size, timing of ovulation, and male behavior in wild West African chimpanzees
Female sexual swelling size, timing of ovulation, and male behavior in wild West African chimpanzees
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DOI：
10.1016/j.yhbeh.2004.03.013
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发表时间：
2004-08-01
影响因子：
3.5
通讯作者：
Boesch, C
中科院分区：
文献类型：
--
作者：
Deschner, T;Heistermann, M;Boesch, C
在许多凯瑟琳灵长类动物的雌性中，特别是在卵巢周期的中期，可以观察到会阴皮肤的明显肿胀。这一特征的功能意义仍然知之甚少。最近，两种假说——“可靠指标”假说和“分级信号”假说——引起了人们的注意，这两种假说不仅考虑了性肿胀的模式，而且还考虑了性肿胀的夸张大小。在这里，我们通过结合(i)雌性性肿胀的直接尺寸测量（来自视频捕获），（ii）通过雌激素偶联物和妊娠二醇葡萄糖醛酸酯（PdG）的酶免疫测定来指示排卵时间的尿激素数据，以及（iii）在12只野生黑猩猩的36个排卵周期中对雄性交配努力的行为观察，对这些假设做出的几个预测进行了测试。我们能够证明(i)即使在传统定义的最大肿胀期，肿胀大小的进一步轻微增加表明接近排卵，（ii）雄性交配兴趣根据肿胀大小的变化而变化。此外，在排卵期的绝对肿胀大小增加，随着受孕周期的减少，雄性领袖与雌性的联系更多。最后，当在几个“最大”肿胀的雌性之间做出选择时，雄性领袖更喜欢处于其周期的繁殖期的雌性，而不是当时肿胀最大的雌性。因此，我们的大多数发现与分级信号假设的预测一致，而没有一个发现支持可靠指标假设。(C) 2004爱思唯尔公司版权所有。
Conspicuous swellings of the perineal skin can be observed in females of many catharrine primate species particularly during the middle stages of the ovarian cycle. The functional significance of this trait remains poorly understood. Recently, two hypotheses, the "reliable indicator" hypothesis and the "graded signal" hypothesis that take into account not only the pattern but also the exaggerated size of sexual swellings, have gained attention. Here we test several predictions made by these hypotheses by combining (i) direct size measures (from video captures) of female sexual swellings with (ii) urinary hormone data to indicate timing of ovulation through enzyme immunoassay measurements of estrone conjugates and pregnanediol glucuronide (PdG) and (iii) behavioral observations of male mating efforts throughout 36 ovulatory cycles in 12 wild chimpanzees. We are able to show that (i) even within the traditionally defined maximum swelling period, further slight increases in swelling size indicate approaching ovulation, and (ii) that male mating interest changes according to the changes in swelling size. Furthermore, absolute swelling size during the periovulatory period increases and the alpha male associates more with females as the number of cycles to conception decreases. Finally, when having the choice between several "maximally" tumescent females, the alpha male prefers the female that is in the fertile phase of her cycle rather than that with the biggest swelling at that time. Thus, most of our findings are in line with the predictions of the graded signal hypothesis while none of them would support the reliable indicator hypothesis. (C) 2004 Elsevier Inc. All rights reserved.