Department of Evolutionary Anthropology, Duke University, Durham, NC, USA.
Department of Psychology, California National Primate Research Center, University of California-Davis, Davis, CA, USA.
Sci Rep. 2021 Feb 12;11(1):3746. doi: 10.1038/s41598-021-83342-6.
Contemporary theory that emphasizes the roles of oxytocin and vasopressin in mammalian sociality has been shaped by seminal vole research that revealed interspecific variation in neuroendocrine circuitry by mating system. However, substantial challenges exist in interpreting and translating these rodent findings to other mammalian groups, including humans, making research on nonhuman primates crucial. Both monogamous and non-monogamous species exist within Eulemur, a genus of strepsirrhine primate, offering a rare opportunity to broaden a comparative perspective on oxytocin and vasopressin neurocircuitry with increased evolutionary relevance to humans. We performed oxytocin and arginine vasopressin 1a receptor autoradiography on 12 Eulemur brains from seven closely related species to (1) characterize receptor distributions across the genus, and (2) examine differences between monogamous and non-monogamous species in regions part of putative "pair-bonding circuits". We find some binding patterns across Eulemur reminiscent of olfactory-guided rodents, but others congruent with more visually oriented anthropoids, consistent with lemurs occupying an 'intermediary' evolutionary niche between haplorhine primates and other mammalian groups. We find little evidence of a "pair-bonding circuit" in Eulemur akin to those proposed in previous rodent or primate research. Mapping neuropeptide receptors in these nontraditional species questions existing assumptions and informs proposed evolutionary explanations about the biological bases of monogamy.
强调催产素和血管升压素在哺乳动物社会性中的作用的当代理论受到了开创性田鼠研究的影响，这些研究揭示了交配系统的种间神经内分泌回路的变异。然而，将这些啮齿动物的发现解释和转化为其他哺乳动物群体，包括人类，存在很大的挑战，这使得对非人类灵长类动物的研究至关重要。在灵长类动物的strepsirrhine 中存在一夫一妻制和非一夫一妻制的物种，这为扩大对催产素和血管升压素神经回路的比较视角提供了难得的机会，增加了与人类的进化相关性。我们对来自七个密切相关物种的 12 只 Eulemur 大脑进行了催产素和精氨酸血管升压素 1a 受体放射自显影，以（1）描述该属中受体的分布情况，以及（2）检查一夫一妻制和非一夫一妻制物种之间在假定的“配对结合回路”区域的差异。我们发现 Eulemur 存在一些与嗅觉导向的啮齿动物相似的结合模式，但也存在与更具视觉导向的类人猿一致的模式，这与狐猴在单孔目灵长类动物和其他哺乳动物群体之间的“中间”进化生态位一致。我们几乎没有发现 Eulemur 中类似于先前在啮齿动物或灵长类动物研究中提出的“配对结合回路”的证据。在这些非传统物种中映射神经肽受体质疑了现有假设，并为提出关于一夫一妻制的生物学基础的进化解释提供了信息。
