Diet or exercise? How do birds cope with transitions in workload associated with parental care or fledging?

饮食还是运动？

• 批准号: RGPIN-2018-03949
• 负责人: Williams, Tony
• 金额: $ 4.01万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=690547
• 关键词: Diet; exercise; How; do; birds

Exercise can be defined as physical activity involving movement supported by sustained locomotor performance, cardiovascular adaptations, and increases in energy expenditure above basal levels. Such a broad definition can theoretically be applied to many routine activities in free-living animals, e.g. foraging, escaping predators, finding mates, providing parental care. These activities are essential for reproduction and survival, and costs of under-performing' are a matter of life and death for free-living animals unlike human athletes at the Olympics. However, it's unclear if concepts such as “exercise” and “training” apply to free-living animals? Do natural populations harbour “couch potatoes” and athletes? Do free-living animals “train” to improve their performance in fitness-related activities (e.g. feeding chicks) and how do animals prepare for, and deal with, rapid transitions in workload or locomotor performance (i.e. “getting up off the couch”)?***In a free-living population of European starlings (Sturnus vulgaris) we focus on two phases of breeding that involve natural, abrupt changes in “workload”: a) from incubation (relatively sedentary) to chick-rearing (highly active) in adult females, and b) from enforced inactivity as nestlings to sustained flight at fledging in young birds. Research will integrate life-history, ecology, behaviour and physiology. In adults, we will directly manipulate costs of workload (using wing-clipping) or the benefit of workload (using egg removal to delay hatching and, thus, reproductive value' of investing in chicks). We will monitor activity of all females 24/7 using an automated radio tracking, obtain detailed information on foraging behaviour using accelerometers, night-vision and video cameras, and combine this with comprehensive physiological analysis (a suite of 15 physiological traits). We will test the hypotheses that female parents use a relatively simple physiological adaptation (mass loss) to adjust to varying workload demands, i.e. they “diet”. We will also explore the significance of novel' aspects of behaviour associated with parental care (e.g. nocturnal activity). Are these important behaviours allowing foraging for self-maintenance, or perhaps even opportunities for “exercise” allowing birds to get in shape ready for chick-rearing? In chicks, we will directly manipulate development (e.g. using hormonal treatment) to test the hypothesis that individual variation in growth rate is constrained by physiological mechanisms and that physiological maturity at fledging (not somatic maturity) is the main determinant of post-fledging behaviour, flight ability and survival. In addition, we will test the idea that chicks use “push-ups” as a form of pre-fledging exercise to assess their body mass and determine their required pre-fledging mass recession to optimise flight ability after fledging.**

运动可以定义为涉及由持续运动表现、心血管适应和能量消耗增加至基础水平以上支持的运动的身体活动。这样一个广泛的定义理论上可以应用于自由生活动物的许多日常活动，例如觅食、逃避掠食者、寻找伴侣、提供父母照顾。这些活动对于繁殖和生存至关重要，与奥运会上的人类运动员不同，对于自由生活的动物来说，表现不佳的代价是生死攸关的问题。然而，尚不清楚“运动”和“训练”等概念是否适用于自由生活的动物？自然人群中是否存在“沙发土豆”和运动员？自由生活的动物是否通过“训练”来提高其在健身相关活动（例如喂养雏鸡）中的表现？动物如何准备和应对工作量或运动表现的快速转变（即“从沙发上站起来”）？***在自由生活的欧洲椋鸟（Sturnus vulgaris）种群中，我们重点关注涉及“工作量”自然突然变化的两个繁殖阶段：a）从孵化开始 成年雌鸟从（相对久坐）到养育雏鸟（高度活跃），b）从雏鸟时被迫不活动到幼鸟在羽翼未丰时持续飞行。研究将整合生活史、生态学、行为学和生理学。对于成年人，我们将直接操纵工作量成本（使用剪翼）或工作量收益（使用取出蛋来延迟孵化，从而延迟投资雏鸡的繁殖价值）。我们将使用自动无线电跟踪技术 24/7 监控所有雌性的活动，使用加速度计、夜视仪和摄像机获取有关觅食行为的详细信息，并将其与全面的生理分析（一套 15 种生理特征）相结合。我们将测试这样的假设：女性父母使用相对简单的生理适应（质量损失）来适应不同的工作量需求，即她们“节食”。我们还将探讨与父母照顾相关的行为的新颖方面（例如夜间活动）的重要性。这些重要的行为是否允许为了自我维持而觅食，或者甚至可能提供“锻炼”的机会，让鸟类为养育雏鸟做好准备？在雏鸡中，我们将直接操纵发育（例如使用激素治疗）来检验以下假设：生长速度的个体差异受到生理机制的限制，并且羽翼成熟时的生理成熟度（而不是体细胞成熟度）是羽翼后行为、飞行能力和生存的主要决定因素。此外，我们将测试雏鸟使用“俯卧撑”作为羽翼前运动的一种形式的想法，以评估其体重并确定其所需的羽翼前质量衰退，以优化羽翼后的飞行能力。 **