Kohli Amanpreet K, Lindauer Alexa L, Brannelly Laura A, Ohmer Michel E B, Richards-Zawacki Cori, Rollins-Smith Louise, Voyles Jamie
Physiol Biochem Zool. 2019 May/Jun;92(3):339-348. doi: 10.1086/703137.
Drought can heavily impact aquatic ecosystems. For amphibian species that rely on water availability for larval development, drought can have direct and indirect effects on larval survival and postmetamorphic fitness. Some amphibian species can accelerate the timing of metamorphosis to escape drying habitats through developmental plasticity. However, trade-offs associated with premature metamorphosis, such as reduced body size and altered immune function in the recently metamorphosed individual, may have downstream effects on susceptibility to disease. Here, we review the physiological mechanisms driving patterns in larval amphibian development under low water conditions. Specifically, we discuss drought-induced accelerated metamorphosis and how it may alter immune function, predisposing juvenile amphibians to infectious disease. In addition, we consider how these physiological and immunological adjustments could play out in a lethal disease system, amphibian chytridiomycosis. Last, we propose avenues for future research that adopt an ecoimmunological approach to evaluate the combined threats of drought and disease for amphibian populations.
干旱会对水生生态系统产生重大影响。对于依赖水源进行幼体发育的两栖动物物种而言，干旱会对幼体存活及变态后的适应性产生直接和间接影响。一些两栖动物物种可通过发育可塑性加速变态时间，以逃离干涸的栖息地。然而，与过早变态相关的权衡，比如新变态个体的体型减小和免疫功能改变，可能会对疾病易感性产生下游影响。在此，我们综述了低水条件下驱动两栖动物幼体发育模式的生理机制。具体而言，我们讨论干旱诱导的加速变态以及它如何改变免疫功能，使幼年两栖动物易患传染病。此外，我们考虑这些生理和免疫调节在致命疾病系统——两栖类壶菌病中会如何表现。最后，我们提出未来研究的方向，即采用生态免疫学方法评估干旱和疾病对两栖动物种群的综合威胁。
