Combrink Lucia L, Bronikowski Anne M, Miller David A W, Sparkman Amanda M
Westmont College Santa Barbara CA USA.
Iowa State University Ames IA USA.
Ecol Evol. 2021 Feb 16;11(7):3239-3250. doi: 10.1002/ece3.7273. eCollection 2021 Apr.
Changing environments result in alterations at all levels of biological organization, from genetics to physiology to demography. The increasing frequency of droughts worldwide is associated with higher temperatures and reduced precipitation that can impact population persistence via effects on individual immune function and survival.We examined the effects of annual climate variation on immunity in two sympatric species of garter snakes from four populations in California over a seven-year period that included the record-breaking drought.We examined three indices of innate immunity: bactericidal competence (BC), natural antibodies (NABs), and complement-mediated lysis (CL).Precipitation was the only climatic variable explaining variation in immune function: spring precipitation of the current year was positively correlated to BC and NABs, whereas spring precipitation of the previous year was positively correlated to BC and NABs. This suggests that experiences a physiological time-lag in response to reduced precipitation, which may reflect lack of capital for investment in immunity in the year following a dry year.In general, our findings demonstrate compelling evidence that climate can influence wild populations through effects on physiological processes, suggesting that physiological indices such as these may offer valuable opportunities for monitoring the effects of climate.
环境变化会导致生物组织从基因到生理再到种群统计学等各个层面发生改变。全球干旱频率的增加与气温升高和降水减少有关，而这会通过对个体免疫功能和生存的影响来冲击种群的存续。在一个包括破纪录干旱年份的七年期间，我们研究了加利福尼亚四个种群中两种同域分布的束带蛇的年度气候变化对免疫的影响。我们检测了三种先天免疫指标：杀菌能力（BC）、天然抗体（NABs）和补体介导的细胞溶解（CL）。降水量是解释免疫功能变化的唯一气候变量：当年春季降水量与BC和NABs呈正相关，而前一年春季降水量与BC和NABs呈正相关。这表明在应对降水减少时存在生理时间滞后，这可能反映了干旱年份之后一年用于免疫投资的资源不足。总体而言，我们的研究结果有力地证明，气候可通过对生理过程的影响来影响野生种群，这表明此类生理指标可能为监测气候影响提供宝贵机会。
