CAREER: Mechanisms of seasonal reproduction in the tropics

职业：热带地区季节性繁殖的机制动物面临的关键挑战是选择繁殖的时间以最大限度地提高后代的存活率。我们对动物繁殖时间的了解大多来自对中高纬度物种的研究。对于这些动物来说，白天长度的变化是它们用来预测季节的主要线索，从而确定季节变化的时间。然而，大多数动物生活在热带纬度地区，那里白天长度的季节性变化很小。然而，许多热带物种仍然按季节繁殖，而且似乎许多物种依赖于更多的局部线索来进行时间繁殖。这可能导致邻近种群之间生殖时间的巨大差异。先前的研究描述了厄瓜多尔赤道附近的红颈麻雀（斑纹雀）种群，它们之间只有25公里的距离，但在一年中的不同时间繁殖。有趣的是，这些人群在基因上也出现了分化。在这个系统中，白昼长度不随季节变化，为进一步研究季节性繁殖机制提供了理想的机会。本研究将从环境和社会因素、内源节律、繁殖同步性、种群遗传分化和营养等方面对季节性繁殖进行研究。这个项目的教育部分有两个主要组成部分。在第一部分，厄瓜多尔当地人和学生将被纳入研究计划，主要是作为该领域的研究助理。第二部分，将在弗吉尼亚理工大学开设一门外国研究课程，让学生了解厄瓜多尔的文化和自然。通过这个项目，每年有12名学生将前往厄瓜多尔一个月，在四个实地地点与当地人互动，体验地球上生物多样性最丰富的地方之一。其中一些学生也可能留在厄瓜多尔从事研究项目。该奖项由美国国家科学基金会国际科学与工程办公室共同资助。

CAREER: Mechanisms of Seasonal Reproduction in the TropicsIgnacio T. MooreVirginia TechA crucial challenge that animals face is timing reproduction to maximize offspring survival. Most of our understanding of how animals time reproduction comes from studies of mid- to high latitude species. For these animals, changes in day length are the primary cue they use to predict seasons and thus time seasonal processes. However, the majority of animals inhabit tropical latitudes where seasonal changes in day length are minimal. Yet many tropical species still breed seasonally and it appears that many rely on more localized cues to time reproduction. This can lead to wide disparity in reproductive timing between populations in close proximity. Previous studies have described populations of rufous-collared sparrows (Zonotrichia capensis) near the equator in Ecuador, that are separated by only 25km, yet breed at very different times of years. Interestingly, these populations have also diverged genetically. This system, where day length does not change seasonally, provides an ideal opportunity to further investigate mechanisms of seasonal reproduction. The proposed studies will investigate seasonal reproduction in terms of environmental and social cues, endogenous rhythms, breeding synchrony, population genetic differentiation, and nutrition. There are two primary components of the education portion of this project. For the first part, Ecuadorian locals and students will be incorporated into the research program, primarily as research assistants in the field. For the second part, a foreign studies class will be initiated at Virginia Tech to expose students to the culture and nature of Ecuador. Through this program, twelve students per year will travel for a month to Ecuador, interact with locals at four field sites and experience one of the most bio-diverse places on earth. Some of these students may also stay in Ecuador and work on the research project. This award is co-funded by the NSF's Office of International Science and Engineering.