Doctoral Dissertation Improvement: Endocrine and Behavioral Correlates of Female Social Dominance in Eulemur

雌性社会优势（FSD）是大多数马达加斯加狐猴的特征，占所有灵长类动物的近30%;然而，人们对这种不寻常现象的进化或机制知之甚少。与FSD相关的是女性的一系列行为、生理和形态特征，这些特征暗示（作为一种可能的机制）通过雄激素暴露的“男性化”。鉴于这种关联，博士生Joseph Petty（杜克大学）在克莉丝汀Drea博士的指导下开展的这个项目采取了比较和综合的方法来研究神经内分泌系统，特别是雄激素在调节狐猴FSD中的作用。研究6个密切相关的Eulemur物种的混合性别对，表现出梯度的行为变化，从积极的FSD性别之间的共同优势，该项目将描述每个物种的两性间优势，从属关系和侵略的表达。通过分析血液样本中的类固醇激素雄烯二酮（A4）、睾酮（T）和雌二醇（E2）以及神经递质5-羟色胺（5-HT），它将进一步提供有关行为神经内分泌相关性的新信息。最后，为了提供与FSD相关的行为和神经内分泌网络之间跨物种直接因果关系的证据，将使用促性腺激素释放激素拮抗剂（antide）对内分泌系统进行实验操作，评估雌性狐猴雄性化行为的行为和社会影响。该项目独特的比较和实验视角将提供对雌性狐猴进化的更多理解。在灵长类动物社会系统中的主导地位，以及对自然循环激素在调节雌性行为中的直接激活作用的洞察。它的非传统的重点有可能帮助更新目前的性选择的定义，以更好地反映在女性的重要性内的性竞争，并改变目前的理解的生理学和表达的社会dominance.This项目将在杜克狐猴中心在达勒姆，北卡罗来纳州，在那里它提供了与研究，技术和教育人员合作的机会。通过这些合作，该项目促进了本科研究人员的指导，与狐猴生物学和保护相关的信息的传播，公众宣传，以及儿童的动手科学经验。

Female social dominance (FSD) over males characterizes most Malagasy lemurs, which represent almost 30% of all primates; yet, little is known about the evolution or mechanism of this unusual phenomenon. Associated with FSD is a suite of behavioral, physiological, and morphological traits in females that implicates (as a possible mechanism) 'masculinization' via androgen exposure. In light of this association, this project by doctoral student Joseph Petty (Duke University), under the guidance of Dr. Christine Drea, takes a comparative and integrative approach to investigating the role of the neuroendocrine system, particularly androgens, in regulating FSD in lemurs. Studying mixed-sex pairs of six closely related Eulemur species that express a gradient of behavioral variation, from aggressive FSD to co-dominance between the sexes, this project will characterize the expression of intersexual dominance, affiliation, and aggression for each species. It will further provide novel information about the neuroendocrine correlates of behavior through the analysis of blood samples for the steroid hormones androstenedione (A4), testosterone (T), and estradiol (E2), as well as the neurotransmitter serotonin (5-HT). Lastly, to provide evidence of a direct causal linkage across species between behavior associated with FSD and neuroendocrine networks, the endocrine system will be experimentally manipulated, using a gonadotrophin-releasing hormone antagonist (antide), to assess the behavioral and social effects on masculinized behavior in female lemurs.This project's unique comparative and experimental perspective will provide an increased understanding of the evolution of female dominance in primate social systems, as well as insight into the direct activational role of naturally circulating hormones in the regulation of female behavior. Its nontraditional focus has the potential to help update current definitions of sexual selection to better reflect the importance of intrasexual competition in females and to transform current understanding of the proximate mechanisms that underlie the physiology and expression of social dominance.This project will be conducted at the Duke Lemur Center in Durham, NC, where it provides opportunities for collaborations with research, technical, and educational staff. Through these collaborations, this project facilitates mentorship of undergraduate researchers, dissemination of information relevant to lemur biology and conservation, public outreach, and hands-on science experience for children.