SGER: Reproductive Biology of Female King Penguins

SGER：雌性王企鹅的生殖生物学

• 批准号: 0128913
• 负责人: Paul Nolan
• 金额: $ 1.8万
• 依托单位: Auburn University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-15 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0128913&HistoricalAwards=false
• 关键词: SGER; Reproductive; Biology; Female; King

Considerable evidence has accumulated that female birds may exert control over the sex ratio of their offspring. Under optimal conditions, more female chicks are produced; and under poor environmental conditions, more of the young are males. There are several plausible explanations for this. In some cases, young males disperse and so under stressful conditions do not compete with parents or siblings. In other instances where habitat conditions are favorable, mothers with new chicks are assisted by older female offspring, increasing reproductive success. In species that lay clutches with multiple eggs, there can be chicks of both sexes and self-assessment of parent condition may not be as crucial. However, in other species such as penguins, only one or two eggs are laid during each breeding season. In this situation, the application of the strategy of sex ratio allocation requires that females must be very capable of assessing their condition and that of their mates. This Small Grant for Exploratory Research will investigate the sex ratio of king penguin chicks relative to the condition of the parents to determine if females are controlling the gender of chicks. Sex determination will be accomplished by DNA analyses of blood samples, a new method to be tested on king penguins in this project. Quantifying parental condition will be done by several standard methods, including measures of body size, parasite load, and immunocompetence. This study will also explore the possibility that plumage coloration is an indicator of condition in penguins as it is in other bird and fish species. Plumage color is from diet-derived carotenoids and may be a useful proxy for evaluating health and fitness. Penguins are dominant predators in their environment and shifts in a population parameter as fundamental as offspring sex ratio might reflect changes in climate or in distribution and abundance of food resources. The results of this work, which will be conducted in collaboration with scientists from the French Antarctic Program, will provide a better understanding of penguin population dynamics and the complex mechanisms of environmental biofeedback.

大量的证据表明，雌鸟可以控制其后代的性别比例。在最佳条件下，会产生更多的雌性小鸡;在恶劣的环境条件下，更多的年轻人是男性。 对此有几种合理的解释。在某些情况下，年轻的男性分散，因此在紧张的条件下不与父母或兄弟姐妹竞争。在其他栖息地条件有利的情况下，有新小鸡的母亲由年长的雌性后代协助，增加了繁殖成功率。在产卵多个蛋的物种中，可能有两种性别的小鸡，对父母状况的自我评估可能不那么重要。然而，在其他物种，如企鹅，只有一个或两个蛋产在每个繁殖季节。在这种情况下，性别比例分配策略的应用要求雌性必须非常有能力评估自己和配偶的状况。这项探索性研究的小额赠款将调查王企鹅小鸡的性别比例与父母的状况，以确定雌性是否控制小鸡的性别。性别鉴定将通过血液样本的DNA分析来完成，这是一种新的方法，将在该项目中对王企鹅进行测试。将通过几种标准方法对亲代状况进行定量，包括测量体型、寄生虫负荷和免疫活性。这项研究还将探讨羽毛颜色是企鹅状况的一个指标的可能性，因为它是在其他鸟类和鱼类。羽毛的颜色来自饮食中的类胡萝卜素，可能是评估健康和健身的有用代表。企鹅是其环境中占主导地位的捕食者，其后代性别比例等基本人口参数的变化可能反映了气候或食物资源分布和丰富程度的变化。这项工作将与法国南极方案的科学家合作进行，其结果将使人们更好地了解企鹅种群动态和环境生物反馈的复杂机制。