Caselli Christini B, Ayres Paulo H B, Castro Shalana C N, Souto Antonio, Schiel Nicola, Miller Cory T
Laboratório de Etologia Teórica e Aplicada, Departamento de Biologia, Universidade Federal Rural de Pernambuco, Recife, Pernambuco, Brazil.
Laboratório de Etologia, Departamento de Zoologia, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil.
Anim Behav. 2018 Feb;136:137-146. doi: 10.1016/j.anbehav.2017.12.009. Epub 2018 Feb 6.
In cooperatively breeding species, encounters with intruders may serve multiple functions ranging from reaffirming group territory ranges to facilitating assessments for additional breeding opportunities. While these distinctive events offer the opportunity to investigate the delicate balance of these social dimensions within animal societies, their unpredictable occurrence makes witnessing and controlling these events in the wild particularly challenging. Here we used a field playback approach to simulate conspecific territorial incursions in cooperatively breeding common marmosets () to distinguish between the three following non-mutually exclusive functions of intergroup encounters in this species of New World primate: territorial defense, mate defense, and assessment of breeding opportunities. For these experiments, we systematically broadcast species-typical long-distance contact calls - phees - commonly used in intergroup interactions from the core and periphery of the groups' territories using either male or female vocalizations. Consistent with a territorial defense hypothesis, a group's reaction was independent of the simulated intruder's sex and the response strength was greater when the playback stimulus was broadcast from the core areas of groups' territories relative to stimulus broadcast from periphery areas. However, sex differences in some facets of their responses suggest that this is not the only potential function for these encounters. Mated males and females started to move first in response to simulated intruders of the opposite sex, suggesting that these events offered opportunities to assess extra-pair breeding opportunities, while the occurrence of females' piloerection towards simulated female intruders is suggestive of mate-guarding. These data provide unique experimental evidence for the theory that excursions by conspecific intruders may serve multiple functions in a cooperatively breeding vertebrate and are reflective of the known complexities of common marmoset sociobiology.
在合作繁殖的物种中，与入侵者的相遇可能具有多种功能，从重申群体领地范围到促进对额外繁殖机会的评估。虽然这些独特的事件为研究动物社会中这些社会维度的微妙平衡提供了机会，但它们不可预测的发生使得在野外目睹和控制这些事件极具挑战性。在这里，我们采用野外回放方法，模拟合作繁殖的普通狨猴（ ）中同种个体的领地入侵，以区分这种新大陆灵长类动物群体间相遇的以下三种并非相互排斥的功能：领地防御、配偶防御和繁殖机会评估。对于这些实验，我们使用雄性或雌性发声，从群体领地的核心和边缘系统地播放群体间互动中常用的典型物种远距离接触叫声——“phees”。与领地防御假说一致，群体的反应与模拟入侵者的性别无关，并且当回放刺激从群体领地的核心区域播放时，反应强度比从边缘区域播放时更大。然而，它们反应的某些方面存在性别差异，这表明这不是这些相遇的唯一潜在功能。已配对的雄性和雌性首先对异性模拟入侵者做出反应开始移动，这表明这些事件提供了评估婚外繁殖机会的机会，而雌性对模拟雌性入侵者出现竖毛反应则表明存在配偶守护行为。这些数据为同种入侵者的侵入在合作繁殖脊椎动物中可能具有多种功能这一理论提供了独特的实验证据，并且反映了普通狨猴社会生物学已知的复杂性。
