Méndez-Cárdenas Maria G, Zimmermann Elke
Institute of Zoology, University of Veterinary Medicine Hannover, D-30553 Hannover, Germany.
Am J Phys Anthropol. 2009 Aug;139(4):523-32. doi: 10.1002/ajpa.21017.
Duetting is defined as an interactively organized pair display in which one pair partner coordinates its vocalizations in time with those of the other. It is widespread among tropical birds and cohesive pair-living primates, in which it is suggested to strengthen pair bonds. We know very little about the presence and function of duetting in dispersed pair-living mammals. We studied duetting behavior in a solitary foraging, but pair-sleeping, primate, the Milne Edwards' sportive lemur, in a dry deciduous forest of north-western Madagascar. We radio-tracked six pairs throughout 1 year and recorded their sleeping sites and associations, home-range use, and vocal and behavioral interactions. Three different periods were covered (mating, pregnancy, and offspring care). Sleeping partners form long-term pair bonds, indicated by an almost exclusive pair-specific usage of sleeping sites and home-ranges across periods. We explored three functional hypothesis of duetting: mate reunion, pair reunion, and joint-territorial defense. Pairs regularly engaged in duet calling. Duetting increased significantly during the offspring care period. Duetting occurred significantly more often at feeding sites than at sleeping sites. Pair partners synchronized behavioral activities after duetting. The activity most often synchronized was locomotion. Pair partners played an equal role in duetting with no difference between sexes in starting or terminating duetting. Altogether, our results provide support for the hypothesis that in dispersed pair-living primates, duetting evolved as a mechanism to coordinate activities between pair partners dispersed in space, to strengthen pair bonds, and, perhaps, to limit infanticide and nutritional stress in lactating females.
二重唱被定义为一种互动式组织的配对展示，其中一对伙伴会使其发声与另一对伙伴的发声在时间上同步。它在热带鸟类和群居的灵长类动物中很普遍，有人认为它能加强配偶关系。我们对独居但成对睡觉的哺乳动物中二重唱的存在和功能了解甚少。我们在马达加斯加西北部的一片干燥落叶林中，研究了一种独居觅食但成对睡觉的灵长类动物——米尔恩·爱德华兹倭狐猴的二重唱行为。我们在一年的时间里对六对倭狐猴进行了无线电追踪，记录了它们的睡眠地点和关联情况、活动范围的使用情况以及声音和行为互动。研究涵盖了三个不同时期（交配期、孕期和育幼期）。睡眠伙伴形成长期的配偶关系，这体现在不同时期几乎专门使用特定的睡眠地点和活动范围。我们探讨了二重唱的三个功能假说：配偶团聚、配对团聚和联合领地防御。成对的倭狐猴经常进行二重唱鸣叫。在育幼期，二重唱显著增加。在觅食地点进行二重唱的频率明显高于睡眠地点。成对伙伴在二重唱后会同步行为活动。最常同步的活动是移动。成对伙伴在二重唱中发挥同等作用，在开始或结束二重唱时没有性别差异。总体而言，我们的研究结果支持了这样一种假说，即在独居的成对生活的灵长类动物中，二重唱演变成了一种机制，用于协调分散在空间中的成对伙伴之间的活动，加强配偶关系，也许还能减少哺乳期雌性的杀婴行为和营养压力。
