Data from: Potential for local adaptation in response to an anthropogenic agent of selection: effects of road deicing salts on amphibian embryonic survival and development

The application of millions of tons of road deicing salts every winter in North America presents significant survival challenges to amphibians inhabiting road-side habitats. While much is known of the effects of NaCl on anuran tadpoles, less is known of effects on amphibian eggs, or any caudate life-stage. In addition, little is known of the effects of MgCl2, which is now the 2nd most commonly used road deicer. Most studies have considered amphibians to be helpless victims of deicing salts, and ignore the possibility of the evolution of local adaptation to this stressor. We attempt to address these knowledge gaps and explore this evolutionary potential by examining the effects of NaCl and MgCl2 on the survival and development of eggs from different female rough-skinned newts (Taricha granulosa) from the same population. We demonstrate that both salts, at environmentally relevant concentrations, severely affect the embryonic survival and development of this amphibian, but that the effects of the salt are dependent on the identity of the mother. This female x treatment interaction results in substantial variation in tolerance to road deicing salts among newt families, providing the raw material necessary for natural selection and the evolution of local adaptation in this amphibian.

北美每年冬季施用数百万吨道路融雪盐，对栖息于道路周边生境的两栖动物造成了严峻的生存挑战。尽管学界已对氯化钠（NaCl）对无尾目蝌蚪的影响开展了大量研究，但针对其对两栖动物卵或任何有尾目生活阶段的影响却知之甚少。此外，当前第二大常用道路融雪剂氯化镁（MgCl2）的相关生态效应同样鲜有报道。既往多数研究将两栖动物视为融雪盐的被动受害者，却忽略了当地种群对该胁迫因子演化出适应性的可能性。本研究旨在填补这些认知空白，通过探究氯化钠（NaCl）与氯化镁（MgCl2）对同一种群不同雌性粗皮渍螈（Taricha granulosa）所产卵的存活与发育的影响，探索该类群的演化潜力。研究结果显示，在环境相关浓度下，两种盐类均会显著抑制该两栖动物的胚胎存活与发育，但其影响效果依赖于母本来源。这种母本与处理的交互作用使得不同渍螈家族对道路融雪盐的耐受性存在显著个体差异，为该两栖动物的自然选择与本地适应演化提供了必要的遗传原材料。