Dissertation Research: Endocrine Coupling of Sexually Dimorphic Display Morphology and Aggressive Display Behavior in Two Sister Species

论文研究：两个姐妹物种的两性展示形态和攻击性展示行为的内分泌耦合

• 批准号: 0073203
• 负责人: Diana Hews
• 金额: $ 0.93万
• 依托单位: Indiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0073203&HistoricalAwards=false
• 关键词: Dissertation; Research; Endocrine; Coupling; Sexually

During aggression males often behaviorally advertise signaling traits. Aggression and the structures used in signaling aggression usually are correlated evolutionarily, but among Sceloporus lizard species they can be decoupled. This study will determine how sex steroid hormones control the development of two such male-specific traits: 1) patches of abdominal color, and 2) stereotyped aggressive behavior used to display the patches to opponents. Work will study two Sceloporus sister-species, one with male patches and one in which males have evolutionarily lost the patches. Hatchling hormone levels will be manipulated, and both patch expression and aggression will be scored in adults to test the hypothesis that decoupling of the male patches trait and aggression arises from species differences in hormonal control of the two. Assays of hatchling blood samples will verify that the altered hatchling hormone levels are within natural levels.In many vertebrates, sex hormones (testosterone, estradiol) act during development and adulthood to produce differences between the sexes. Testosterone can be converted to estrogen, which influences development of brain regions involved in aggression. Testosterone also can be converted to 5a-dihydrotestosterone, which often affects development of male traits elsewhere in the body. Decoupling could occur if species vary in these hormonal levels. For example, males of these species may vary in the enzymes needed for these conversions of testosterone. Relatively little is known about the variation in the hormonal mechanisms controlling differences in aggression and in signaling structures in natural populations, as most research focuses on inbred laboratory strains of rodents and domesticated animal breeds.

在攻击过程中，雄性经常在行为上宣传信号特征。攻击性和用于发出攻击信号的结构通常在进化上是相关的，但在Sceloporus蜥蜴物种中，它们可以解耦。这项研究将确定性类固醇激素如何控制两个这样的男性特有特征的发展：1）腹部颜色的补丁，和2）用于向对手展示补丁的刻板攻击行为。 工作将研究两个Sceloporus姐妹物种，一个是男性补丁，另一个是男性进化失去了补丁。 孵化激素水平将被操纵，和补丁的表达和侵略将在成年人进行评分，以测试的假设，即脱钩的男性补丁性状和侵略产生的物种差异激素控制的两个。幼体血液样本的分析将证实幼体激素水平的改变是在自然水平内。在许多脊椎动物中，性激素（睾酮，雌二醇）在发育和成年期间产生性别差异。 睾酮可以转化为雌激素，雌激素会影响与攻击性有关的大脑区域的发育。 睾酮也可以转化为5a-二氢睾酮，这通常会影响身体其他部位男性特征的发育。 如果物种在这些激素水平上存在差异，就会发生脱钩。例如，这些物种的雄性可能在这些睾酮转化所需的酶中有所不同。相对较少的是知道的变化，在激素机制控制的差异，在侵略和信号结构在自然种群，因为大多数研究集中在近交系实验室品系的啮齿动物和驯养的动物品种。