School of Life and Environmental Sciences, Deakin University, 3228 Victoria, Australia.
Department of Biological Sciences, Macquarie University, 2122 New South Wales, Australia.
Gen Comp Endocrinol. 2020 Jan 1;285:113247. doi: 10.1016/j.ygcen.2019.113247. Epub 2019 Aug 17.
Animals time reproductive events to overlap with periods of favorable environmental conditions. However, weather conditions can be unpredictable. Young animals may be particularly susceptible to extreme weather during sensitive developmental periods. Here, we investigated the effects of adverse weather conditions on corticosterone levels (a hormone linked to the avian stress response) and body condition of wild nestling zebra finches (Taeniopygia guttata). We sought to tease apart the direct versus indirect (i.e. parental) effects of weather on nestling physiology and condition by increasing parental work load with a clutch manipulation experiment. We found that high temperatures were associated with lower levels of restraint-induced corticosterone and high wind speeds were associated with higher levels of baseline corticosterone. We found no associations between weather and nestling body condition. However, clutch manipulation did affect body condition, with nestlings from experimentally enlarged clutches in worse condition compared to nestlings from experimentally reduced clutches. Our findings suggest that weather can directly affect wild nestlings via changes in corticosterone levels. Further research is needed to understand how changes in corticosterone levels affect phenotype and survival in wild nestlings. Understanding how developing animals respond to changes in environmental predictability and extreme weather is vital for understanding the potential for rapid adaptation in the face of changing climatic conditions.
动物会选择在环境条件有利的时期进行繁殖。然而，天气条件可能是不可预测的。在敏感的发育阶段，幼小动物可能特别容易受到极端天气的影响。在这里，我们研究了恶劣天气条件对皮质酮水平（与鸟类应激反应有关的激素）和野生雏鸟斑马雀（Taeniopygia guttata）身体状况的影响。我们试图通过巢内操作实验增加亲鸟的工作量，来区分天气对雏鸟生理和状况的直接和间接（即亲鸟）影响。我们发现，高温与较低的束缚诱导皮质酮水平相关，而大风速与较高的基础皮质酮水平相关。我们没有发现天气和雏鸟身体状况之间的关联。然而，巢内操作确实会影响身体状况，与实验中减少的巢相比，实验中扩大的巢的雏鸟状况较差。我们的研究结果表明，天气可以通过皮质酮水平的变化直接影响野生雏鸟。需要进一步的研究来了解皮质酮水平的变化如何影响野生雏鸟的表型和生存。了解发育中的动物如何应对环境可预测性的变化和极端天气，对于理解在气候变化面前快速适应的潜力至关重要。
