Collaborative Research: Modeling organismal responses to changing ecological regimes via investigation of stress, growth and reproduction in the longest-lived mammal

这个项目使用新的技术来分析历史博物馆的鲸须标本(鲸鱼上颌缓慢生长的垂直长条角蛋白)，以研究环境变化如何影响长寿动物。环境变化可能会对野生动物产生戏剧性的影响，但这些影响往往会在多年后缓慢展开，挑战科学家在足够长的时间内收集数据的能力。最近发现，须毛含有荷尔蒙，荷尔蒙随着须毛的生长而沉积，因此一片须毛包含了个体鲸鱼几十年来的繁殖史、压力和总体健康的详细记录。白鲸还含有碳和氮特征，可以重建鲸鱼的饮食和迁徙历史。这个项目将使用这些新技术来分析从19世纪到80年代从弓头鲸(Balaena Mystitus)身上收集的博物馆须毛，这种鲸鱼可以活200年，以调查环境变化对长寿哺乳动物的压力、生长和繁殖的长期、多年的影响。统计建模将把结果放在更广泛的背景下，阐明鲸鱼，进而其他长寿哺乳动物，如何随着时间的推移对环境变化做出反应。该项目将吸引约40名本科生从事史密森研究，培训一名博士后和博士后，在参与的博物馆进行大量公开演讲，让祖先最初收集标本的阿拉斯加原住民社区参与进来，并在科学会议和同行评议的出版物上发布结果，从而有助于更广泛的社会影响。环境变化会对长寿物种造成持续数年的生理影响，但缺乏在必要的十年时间尺度上量化这种影响及其对种群的影响的方法。该项目使用了最近开发的鲸须分析技术来解决这一数据差距，测试了海洋条件的突然变化对个体的压力、生长和繁殖造成随后多年影响的假设，以及这些信息可用于模拟种群水平对当前和预测的环境变化的反应。该项目利用博物馆存档的弓头鲸标本，这些标本之所以被选中，是因为它们的须生长缓慢，寿命极长(200年)，范围大，而且北太平洋冬季和北冰洋夏季栖息地的环境变化得到了很好的记录。从1859-1989年收集的56个须类样本将以2厘米的间隔采样稳定同位素，以4厘米的间隔采样肾上腺、甲状腺和生殖激素，从而能够以大约每月的分辨率重建数十年的个人历史。具体目标包括：(1)确定1977年北太平洋生态系统转变前后青少年的终生内分泌史，使用一组由四种激素组成的小组来评估应激生理学；(2)评估这种应激对幼体生长速度的潜在影响；(3)扩大关于以不同人为和环境影响为特征的时代成年人应激和生殖历史模式的长期数据集；(4)使用所得到的数据来模拟生态变化、个体生理和潜在的人口影响之间的联系，使用干扰的人口后果框架。这一奖项反映了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。

This project uses new techniques to analyze historical museum specimens of whale baleen (long vertical strips of keratin that grow slowly from a whale's upper jaw) to investigate how environmental change affects long-lived animals. Environmental change can have dramatic effects on wildlife, but these effects often unfold slowly across many years, challenging scientists' ability to gather data across sufficient stretches of time. It has recently been discovered that baleen contains hormones that are deposited as the baleen grows, such that one piece of baleen contains a detailed record of individual whales’ reproductive history, stress and general health across decades. Baleen also contains carbon and nitrogen signatures that enable reconstruction of the whale's diet as well as its migration history. This project will use these new techniques to analyze museum baleen collected from the 1800s to the 1980s from bowhead whales (Balaena mysticetus), which can live 200 years, to investigate long-term, multi-year impacts of environmental change on stress, growth and reproduction in a long-lived mammal. Statistical modeling will put results into a broader context, illuminating how whales, and by extension other long-lived mammals, respond to environmental change over time. The project will engage ~40 undergraduates in Smithsonian-based research, train a postdoc and PhD student, result in numerous public talks at participating museums, involve Native Alaskan communities whose ancestors originally collected the specimens, and distribute results at scientific conferences and in peer-reviewed publications, thus contributing to broader societal impacts.Environmental change causes physiological impacts that can last years in long-lived species, yet there is a dearth of methods for quantifying such impacts and their population effects across the necessary decadal timescales. This project employs recently developed analytic techniques for whale baleen to address this data gap, testing the hypothesis that sudden changes in marine conditions cause subsequent multi-year impacts on stress, growth and reproduction of individuals, and that this information can be used to model population-level responses to current and predicted environmental change. The project utilizes archived museum specimens of baleen from bowhead whales (Balaena mysticetus), selected due to their slow-growing baleen, exceptionally long lifespan (200 years), large range, and well-documented environmental shifts in their North Pacific winter and Arctic Ocean summer habitats. Fifty-six specimens of baleen collected from 1859-1989 will be sampled at 2-cm intervals for stable isotopes and 4-cm intervals for adrenal, thyroid and reproductive hormones, enabling reconstruction of individual histories across decades with approximately monthly resolution. Specific objectives include: (1) Determine lifetime endocrine history of juveniles before and after a well-documented 1977 North Pacific ecological regime shift, using a panel of four hormones to assess stress physiology; (2) Assess potential impacts of such stress on juvenile growth rate; (3) Expand a long-term dataset on historic patterns of stress and reproduction in adults in eras characterized by varying anthropogenic and environmental impacts; (4) Use the resulting data to model linkages between ecological change, individual physiology, and potential population impacts, using the Population Consequences of Disturbance framework.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.