Doctoral Dissertation Research: Endocrine Mediation of Alternative Reproductive Tactics in Anurans

提案0308958 -内分泌介导的替代生殖策略在无尾类PI：迷迭香克纳普和克里斯托弗J. LearyLay摘要生理机制的表达，有助于替代男性交配策略已被广泛研究的鱼类和爬行动物，通常广告使用视觉信号。尽管无尾两栖动物（青蛙和蟾蜍）中替代策略普遍存在，但人们对无尾两栖动物（青蛙和蟾蜍）中调节声音信号产生的过程知之甚少。例如，雄性蟾蜍通常会发出声音来吸引配偶，但有些个体会采取替代性的非呼叫“卫星”策略。卫星男性的特点是保持在接近呼叫男性，并试图拦截传入的女性吸引发声的个人。理论预测，这些可塑的成年人行为表型应该受到激素的影响，这些激素介导了一种行为的表达。在无尾两栖类中，人们认为叫声和非叫声行为之间的交替与循环中的“压力”类固醇激素皮质酮和性类固醇（雄激素）水平之间的相互作用有关，这种相互作用是由发声过程中能量储备的消耗驱动的。初步的数据支持皮质酮水平和消耗的能量储备在发声的较量之间的关系，但表明呼叫和卫星行为之间的交替是独立的雄激素。拟议的研究将测试一种替代模型，以确定蟾蜍雄性生殖行为的生理基础。

Proposal 0308958 - Endocrine mediation of alternative reproductive tactics in anurans PIs: Rosemary Knapp and Christopher J. LearyLay SummaryPhysiological mechanisms contributing to the expression of alternative male mating tactics have been studied most extensively in fishes and reptiles that typically advertise using visual signals. Less is known regarding processes regulating vocal signal production in anuran amphibians (frogs and toads), despite the pervasiveness of alternative tactics in this group. For example, male toads typically vocalize to attract mates, but some individuals adopt alternative non-calling "satellite" tactics. Satellite males characteristically remain in close proximity to calling males and attempt to intercept incoming females attracted to vocalizing individuals. Theory predicts that these plastic adult behavioral phenotypes should be subject to effects of hormones that mediate the expression of one behavior over the other. In anurans, it is thought that alternation between calling and non-calling behavior is related to a reciprocal interaction between circulating levels of the "stress" steroid hormone corticosterone and sex steroids (androgens) that is driven by depletion of energy reserves during vocalization. Preliminary data support a relationship between corticosterone levels and depletion of energy reserves during vocal bouts but indicate that alternation between calling and satellite behavior is independent of androgens. The proposed studies will test an alternative model to determine the physiological basis for male reproductive behavior in toads.