SGER - Hormones, Behavior and Life Cycles: Predictors of Sensitivity to Global Change?

全球气候变化正在导致迁徙、繁殖季节和生物生命周期其他方面的剧烈调整。一些种群繁荣，一些种群减少，还有一些种群保持不变。为什么会有这种变化？最近发现了一种鸣禽（白冠麻雀，Zonotrichia leucophrys pugetensis），它们在西雅图的城市栖息地定居，并利用华盛顿州喀斯喀特山脉的人类干扰区。这些鸟在新的栖息地定居下来，在过去的二十年里，它们的数量急剧增加。这些种群现在与高山亚种（Z.l. gambelii）接触，后者没有改变其活动范围。此外，还有一种非迁徙的沿海亚种（Z.l. nuttalli）也没有改变其活动范围。越来越多的数据表明，亚种正在改变其活动范围，同时也在改变激素行为机制，以适应高山亚种。这包括荷尔蒙对压力的反应。在高山亚种和北部亚种中，这些响应在春季向上调节，而在筑巢开始时向下调节，但在沿海亚种中没有调节（包括祖居地、沿海栖息地的pugetensis种群）。在城市和高山栖息地定居的pugetensis种群现在调节它们对急性应激的激素反应，就像北部和自然高山亚种一样。目前的项目将确定这是一种表观遗传效应还是新特征的快速进化。这将包括与未改变其分布范围的亚种z.l gambelii和z.l nuttalli相比，z.l pugetensis祖先种群和先驱种群基因转录的潜在表观遗传调控。这项研究将是细胞和分子技术在与全球变化有关的生态环境中的新融合。至少两名研究生将参与实地工作，并为表观遗传学工作开发分子方法。这个项目可能会成为这两个学生的论文研究重点，本科生也会在今年春夏加入这个项目。

Global climate change is resulting in dramatic adjustments of migrations, breeding seasons and other aspects of the life cycle of organisms. Some populations flourish, others decline and yet others remain unchanged. Why this variation? A population of songbirds (White-crowned Sparrow, Zonotrichia leucophrys pugetensis) has recently been identified that has colonized urban habitat in Seattle as well as taken advantage of human disturbed areas in the Cascade Mountains of Washington State. These birds have settled in new habitat and their populations have expanded dramatically in the last twenty years. These populations are now in contact with alpine sub-species (Z.l. gambelii) that is not changing its range. Furthermore, there is a non-migratory, coastal sub-species (Z.l. nuttalli) that also is not changing its range. Accumulating data show that the sub-species that is changing its range is also changing hormone-behavior mechanisms to match the alpine sub-species. This includes the hormonal responses to stress. These responses are modulated up in the spring and down once nesting begins in the alpine and northern sub-species, but not modulated in the coastal sub-species (including the populations of Z.l. pugetensis in ancestral, coastal, habitat). Populations of Z.l. pugetensis that have colonized urban and alpine habitats now modulate their hormone responses to acute stress as do the northern and natural alpine sub-species. The current project will determine whether this is an epigenetic effect or rapid evolution of new traits. This will include potential epigenetic regulation of gene transcription in ancestral populations and pioneer populations of Z.l. pugetensis, compared with the sub-species Z.l. gambelii and Z.l. nuttalli that are not changing their ranges. This research will be a new blend of cell and molecular techniques in ecological settings in relation to global change. At least two graduate students will be involved in the field work and developing molecular methods for the epigenetic work. This project will likely become the focus for thesis research for these two students and undergraduate students will also join the project through this spring and summer.