Life History and Developmental Variation of Tropical Versus Temperate Passerines

热带与温带雀形目动物的生活史和发育变异

• 批准号: 0543178
• 负责人: Thomas Martin
• 金额: $ 48.35万
• 依托单位: University of Montana
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0543178&HistoricalAwards=false
• 关键词: Life; History; Developmental; Variation; Tropical

Embryonic development is a critical stage in the life of organisms that shapes the physical and internal expression of the organism later in life. It can influence size, shape, and internal quality such as the strength of the immune system and quality of the neural/brain system. Rate of embryonic development varies dramatically among species, with an especially strong difference between tropical and north temperate organisms; tropical organisms develop much slower than organisms in North America, and this is very clear in songbirds. The classic explanation is that slower development is favored because it allows enhanced development of specialized cells, such as the immune system, to yield higher quality offspring. Yet, preliminary data raise questions about this long-standing view. This hypothesis will be explored along with 3 alternative hypotheses for the latitudinal variation in incubation periods of birds: 1) the classic trade-off with offspring quality hypothesis, 2) extrinsic adult mortality, 3) food limitation, and 4) nest predation. Proposed work will examine these hypotheses through continued studies of birds in the Andes of Venezuela to compare with related species in a long-term ongoing study in Arizona. The proposed work will use experimental manipulation of food and other hypothesized factors to test the alternatives, while also examining offspring quality based on size at hatching and measures of immune function.The proposed work has the potential to reverse long-standing views of the causes and consequences of slow development. At the same time, it will provide new insight into ecological factors favoring variation in the rate of development as well as the benefits and costs of that variation to quality of offspring. The proposed work will provide extensive opportunities for the integration and training of large numbers of undergraduate, graduate, and post-doctoral researchers of diverse U.S. and international (Latin American) communities. In short, the proposed work will provide a unique cross-cultural life experience as well as stringent educational and field experience for many undergraduates each year.

胚胎发育是生物生命中的关键阶段，后来塑造了生命中生物体的物理和内部表达。 它可以影响大小，形状和内部质量，例如免疫系统的强度以及神经/脑系统的质量。 物种之间的胚胎发育速率差异很大，热带和北部温带生物之间的差异尤其特别。热带生物的发展速度比北美的生物慢得多，这在鸣禽中非常明显。 经典的解释是，较慢的开发是有利的，因为它允许增强特殊细胞（例如免疫系统）的开发，从而产生更高质量的后代。但是，初步数据引发了有关这种长期观点的问题。 将探讨该假设，以及3种鸟类孵化期纬度变化的替代假设：1）具有后代质量假设的经典折衷，2）外部成人死亡率，3）食物限制和4）巢捕食。拟议的工作将通过对委内瑞拉安第斯山脉的鸟类的持续研究来研究这些假设，以与亚利桑那州正在进行的一项正在进行的研究中与相关物种进行比较。 拟议的工作将使用食物和其他假设因素的实验操作来测试替代方案，同时还根据孵化时的大小和免疫功能的度量来检查后代质量。拟议的工作有可能扭转对慢速发展的原因和后果的长期观点。 同时，它将为生态因素提供新的见解，这些因素有利于发展速度的差异，以及这种变化对后代质量的收益和成本。 拟议的工作将为大量美国和国际（拉丁美洲）社区的大量本科，研究生和博士后研究人员提供广泛的机会。简而言之，拟议的工作将为许多本科生提供独特的跨文化生活经验以及严格的教育和实地经验。