Finkenwirth Christa, Burkart Judith M
Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
Physiol Behav. 2017 May 1;173:79-86. doi: 10.1016/j.physbeh.2017.01.032. Epub 2017 Jan 20.
Cooperatively breeding, group-living common marmosets show differentiated relationships, where more strongly bonded dyads within a group engage more in affiliative interactions than less strongly bonded ones. Intriguingly, recent results suggest that strong bonds do not only occur between breeding partners but between individuals from any sex or status, and that strong-bond partners exhibit correlated oxytocin fluctuations (dyadic oxytocin synchrony, OTS) over a period of six weeks. To date, it is unclear whether such relationships are stable over time and whether they are also reflected in higher partner-specific proactive prosociality. To assess the long-term stability of the relationship structure of common marmoset family groups, we investigated whether hormonal and behavioral markers of group structure (dyadic OTS, dyadic affiliation, and individual group integration) in common marmoset families remained stable over a period of six months. We collected baseline urinary OT and social behavior of 36 dyads from three family groups in a non-reproductive period (period A), and again six months later, around the birth of new infants (period B). Patterns of dyadic OTS, dyadic affiliation, and individual group integration were consistent between the two study periods. Oxytocin data from a fourth group (10 dyads), collected in two non-reproductive periods separated by a period of more than five years, could replicate this finding. Furthermore, OTS was also correlated with proactive prosociality that was assessed experimentally for 38 dyads during an earlier study. These results suggest that differentiated relationships are stable over time, even between group members other than the breeding pair, and that more strongly bonded partners also show higher levels of proactive prosociality. Future studies are necessary to identify whether these relationships have an adaptive function, perhaps with regard to positive consequences on cooperativeness.
合作繁殖、群居的普通狨猴表现出不同的关系，即群体中关系更紧密的二元组比关系不那么紧密的二元组更多地参与亲和互动。有趣的是，最近的研究结果表明，紧密的关系不仅存在于繁殖伙伴之间，也存在于任何性别或地位的个体之间，而且紧密关系的伙伴在六周的时间里表现出相关的催产素波动（二元催产素同步，OTS）。迄今为止，尚不清楚这种关系是否随时间稳定，以及它们是否也反映在更高的特定伙伴主动亲社会行为中。为了评估普通狨猴家族群体关系结构的长期稳定性，我们调查了普通狨猴家族中群体结构的激素和行为标记（二元OTS、二元亲和性和个体群体融入度）在六个月的时间里是否保持稳定。我们在非繁殖期（时期A）收集了三个家族群体中36个二元组的基线尿催产素和社会行为数据，六个月后，在新婴儿出生前后（时期B）再次收集。两个研究时期的二元OTS、二元亲和性和个体群体融入度模式是一致的。来自第四组（10个二元组）的数据，在相隔五年多的两个非繁殖期收集，能够重复这一发现。此外，OTS还与早期研究中对38个二元组进行实验评估的主动亲社会行为相关。这些结果表明，不同的关系随时间是稳定的，即使在繁殖对以外的群体成员之间也是如此，而且关系更紧密的伙伴也表现出更高水平的主动亲社会行为。未来的研究有必要确定这些关系是否具有适应性功能，也许与对合作性的积极影响有关。
