Collaborative Research: RUI: Social modulation of migratory timing and endocrine mechanisms of migration in two flexible migrants

动物迁徙是数千个物种生命周期的核心阶段，它对许多生态系统的动态至关重要，对人类健康有影响，是一个特别容易受到干扰的过程。因此，对移民控制的研究无论从基础还是从应用角度都是至关重要的。了解动物如何决定何时迁徙特别重要，因为这可以决定它们是否在繁殖或越冬的合适时间到达目的地。许多动物成群结队地活动，社会互动和社会线索在动物为迁徙做准备和迁徙过程中做出的决定中被认为是重要的。然而，关于社会线索在决定动物何时开始或结束迁徙中的作用，或者关于社会信号可能通过哪些生理机制影响迁徙时间，人们知之甚少。这一合作项目将利用两种候鸟来解决这两个知识差距，这两种候鸟的迁徙时间表灵活，对社会信息高度敏感。这项工作的结果将增进我们对社会线索如何影响迁徙时机和迁徙的荷尔蒙调节的理解。该项目还将为本科生和研究生提供培训和指导。与该项目有关的外联活动将使小学生和普通公众参与迁徙生物学。大学一级和小学的培训和外联活动将针对传统上在STEM领域代表性不足的群体的个人。这一合作项目的第一个目标是评估社会线索(特别是同种人的迁徙状态)对迁徙时机的影响。将进行实验，以检验鸟类使用同种线索来微调迁徙开始和结束的时间的假设。关于移徙时机的社会线索尚未得到很好的研究，该项目将移徙终止阶段纳入其中，对于促进对这一特别未得到充分研究的移徙阶段的理解将是重要的。该项目的第二个目标是促进对迁徙过渡的内分泌和神经内分泌调节的理解，进一步的目标是研究社会线索如何影响内分泌和神经内分泌参数，从而潜在地改变迁徙时机。因此，研究人员将量化循环中类固醇激素的变化及其受体在大脑和周围组织中的可获得性，跨越迁移状态的转换和退出。这种在迁徙背景下理解内分泌机制的全身方法是独一无二的。研究人员还将实验性地操纵社会线索，以评估内分泌和神经内分泌机制，这些线索可能通过这些机制影响迁徙时机。因此，该项目的结果将极大地拓宽对社会线索和内分泌机制在生命历史转变中的可塑性的作用的理解。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Animal migration is a centrally important life cycle stage for thousands of species, it is critical to the dynamics of many ecosystems, has impacts on human health, and is a process that is particularly prone to disturbance. Thus, research on the control of migration is critical from both basic and applied perspectives. Understanding how animals decide when to move is of particular importance given that this can dictate whether or not they arrive at their destination at an appropriate time for reproduction or overwintering. Many animals move in groups and social interactions and social cues are expected to be important in the decisions that animals make in preparation for and during migration. Yet, there is little known about the role of social cues in determining when animals begin or end migration or about the physiological mechanisms by which social signals might act to influence migratory timing. This collaborative project will address these two knowledge gaps using two species of migratory songbirds that have flexible migratory schedules and that are highly sensitive to social information. Results of this work will advance our understanding of how social cues influence both migratory timing and the hormonal regulation of migration. This project will also provide training and mentoring for undergraduate and graduate students. Outreach activities linked to the project will engage elementary school students and the general public in migratory biology. Training and outreach activities at the university level and in elementary schools will target individuals from groups that are traditionally underrepresented in STEM fields.The first goal of this collaborative project is to evaluate the influence of social cues (specifically, the migratory state of conspecifics) on the timing of migration. Experiments will be carried out to test the hypotheses that birds use cues from conspecifics to fine-tune timing of initiation and termination of migration. Social cues have not been well studied in the context of migratory timing and the project's inclusion of the termination phase of migration will be important in advancing the understanding of this particularly understudied phase of migration. The second goal of the project is to advance understanding of the endocrine and neuroendocrine regulation of migratory transitions, with the further objective of investigating how social cues influence endocrine and neuroendocrine parameters to potentially alter migratory timing. Thus, investigators will quantify changes in circulating steroid hormones and the availability of their receptors in the brain and peripheral tissues across transitions into and out of a migratory state. This type of whole-body approach to understanding endocrine mechanisms in the context of migration is unique. The investigators will also experimentally manipulate social cues to evaluate endocrine and neuroendocrine mechanisms by which these cues might influence migratory timing. The results of this project will thus greatly broaden understanding of the roles of social cues and plasticity of endocrine mechanisms in life history transitions.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.