DISSERTATION RESEARCH: Evolutionary Origin of Behavioral Organization: Constraint or Adaptation?

摘要 建议：#96-23546 PI：Crews Rhen 行为组织的进化起源 在鸟类和哺乳动物中，雌二醇（通过哺乳动物中睾酮的芳构化）在早期发育过程中组织生殖和攻击行为是有据可查的。 在这些群体中，有组织性和异配性之间存在相关性;在哺乳动物中，雄性是有组织的（失去表现雌性典型行为的能力），而在鸟类中，雌性是有组织的（失去表现雄性典型行为的能力）。 异性保留了表现出女性和男性典型行为的能力。 在其他脊椎动物中也观察到类似的基因型性别决定相关性。 另一种解释是：（1）发育限制导致了异配子性别的组织，或者（2）组织和雌雄异体之间存在功能关系。 具有环境性别决定的爬行动物不适合约束范式，因为它们缺乏异配子性别。 相反，如果组织是适应性的，这些物种可能是有组织的。 在这项研究中，胚胎温度（从而性腺性别）和成人激素的操纵将进行区分假说的组织。 对数线性、多变量和路径分析将用于分析生殖和攻击行为。 结果将（1）阐明ESD物种行为变异的近因，（2）首次描述和测试性别决定机制背景下行为组织进化原因的替代假设。

ABSTRACT Proposal: #96-23546 PI: Crews & Rhen Title: Evolutionary origin of behavioral organization Organization of reproductive and aggressive behaviors by estradiol (via aromatization of testosterone in mammals) during early development is well documented in birds and mammals. There is a correlation between the organized and heterogametic sex in these groups; males are organized (lose the ability to display female-typical behavior) in mammals, whereas females are organized (lose the ability to display male-typical behavior) in birds. The opposite sex retains the capacity to display both female- and male-typical behavior. A similar correlation is observed in other vertebrates with genotypic sex determination. Alternate explanations are (1) that a developmental constraint results in organization of the heterogametic sex, or (2) that there is a functional relationship between organization and gonochorism. Reptiles with environmental sex determination do not fit into the constraint paradigm because they lack a heterogametic sex. In contrast, these species may be organized if organization is adaptive. In this study, manipulation of embryonic temperature (and thereby gonadal sex) and adult hormones will be performed to distinguish among hypotheses about organization. Log-linear, multivariate, and path analyses will be used to analyze reproductive and aggressive behaviors. Results will (1) illuminate the proximate cause of behavioral variation in an ESD species, and (2) for the first time delineate and test alternate hypotheses about the evolutionary causes of behavioral organization in the context of sex determining mechanisms.