Same, same, or different? Mechanisms of Parental Care Between Sexes

性别差异是动物行为的共同特征。然而，事实证明，这些行为差异背后的机制很难理解，因为男性和女性的大脑和基因几乎是相同的，而且一种性别的典型行为偶尔也会被异性模仿。该项目的目标是了解激素、神经活动和基因表达如何相互作用，从而导致性别差异和行为逆转。亲代行为是一个有希望的起点，因为许多物种在亲代照顾方面表现出性别差异，以及性别逆转照顾的潜力。该项目利用了新热带毒蛙（dendroates tinctorius）自然发生的亲代灵活性。在这个系统中，雄性是主要的照顾者，雌性只是偶尔接管，为哺乳动物的现有工作提供了重要的补充，在哺乳动物中，亲代照顾偏重于雌性，并且依赖于哺乳。该项目的结果将提供对行为性别差异如何在大脑中编码的新理解，这些差异如何导致不同的行为模式，以及它们可以改变或逆转的条件。该项目将培训各个阶段的研究人员，重点是从STEM中代表性不足的群体招募学员。此外，毒蛙是一种迷人的、有魅力的生物，可以通过“青蛙学校计划”促进对不同受众的教学，包括K-12学生和教师，以及通过社区参与活动的公众。进化、行为和神经生物学交叉的一个基本问题是，新的行为是如何产生并融入现有的神经系统的。跨性别转移，即最初只在一个性别中表现出来的特征在异性身上的出现，被认为是行为进化中一个主要的、未被充分认识的力量。然而，促进与异性生理、神经和分子系统整合的机制在很大程度上是未知的。解决这个谜题与理解行为是如何在组织层面上编码密切相关——从基因到基因网络，到细胞类型，到神经回路，到生理学，再到行为。利用有毒树蛙自然发生的亲代抚育，该项目测试了跨组织层面的机制相互作用形成性别之间的行为灵活性和进化的中心假设。具体来说，该项目将激素和神经活动模式与个体变异和行为的性别差异联系起来，询问雄性和雌性的共有基因和细胞类型是否与亲代抚育有关，并通过追踪激素操纵在组织水平上的影响，对这些假设进行因果检验。跨多个组织级别的数据综合是这项工作的一个关键特征。此外，该项目将有助于培训不同的研究人员和社区参与。项目成果将为理解行为上的性别差异是如何在大脑中编码的，它们可以被改变或逆转的条件，以及潜在的机制是如何在环境、发展和进化中协调复杂行为的。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Sex differences are a common feature of animal behavior. Yet, the mechanisms underlying these behavioral differences have proven difficult to understand because brains and genes are nearly identical between males and females, and behavior typical of one sex may occasionally be performed by the opposite sex. The goal of this project is to understand how hormones, neural activity, and gene expression interact to give rise to sex differences and reversals in behavior. Parental behavioral is a promising starting point, as many species exhibit sex differences in parental care, as well as the potential for sex-reversed care. The project capitalized on naturally occurring parental flexibility in a Neotropical poison frog, Dendrobates tinctorius. Males are the primary care givers in this system, with females only occasionally taking over, providing an important complement to existing work in mammals where parental care is female biased and limited by reliance on lactation. Outcomes of the project will provide new understanding of how behavioral sex differences are coded in the brain, how these differences lead to distinct behavioral patterns, and the conditions under which they can be altered or reversed. The project will train researchers at all stages, with a focus on recruitment of trainees from groups underrepresented in STEM. Additionally, poison frogs are fascinating, charismatic creatures that facilitate teaching of diverse audiences, including K-12 students and teachers through the “Froggers School Program” and the general public through community engagement events. A fundamental question at the intersection of evolution, behavior, and neurobiology is how novel behaviors arise and are incorporated into existing neural systems. Cross-sexual transfer, the emergence of traits initially exhibited only in one sex in the opposite sex, has been proposed as a major, underappreciated force in the evolution of behavior. Yet, the mechanisms that facilitate integration into opposite sex physiological, neural, and molecular systems are largely unknown. Solving this puzzle is intimately tied to understanding how behavior is coded across levels of organization – from genes, to gene networks, to cell types, to neural circuits, to physiology, to behavior. Leveraging naturally occurring parental care in Dendrobates tinctorius poison frogs, this project tests the central hypothesis that mechanistic interactions across levels of organization shape behavioral flexibility and evolution between sexes. Specifically, the project links hormone and neural activity patterns to individual variation and sex differences in behavior, asks whether shared versus distinct genes and cell types are associated with parental care in males and females, and causally tests these hypotheses by tracing the effects of hormone manipulations across levels of organization. Synthesis of data across multiple levels of organization is a key feature of this work. Additionally, the project will contribute to training of diverse researchers and community engagement. Project outcomes will provide inroads to understanding how behavioral sex differences are coded in the brain, the conditions under which they can be altered or reversed, and how underlying mechanisms are environmentally, developmentally, and evolutionarily tuned to coordinate complex behavior.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.