Penney Chantelle M, Burness Gary, Tabh Joshua K R, Wilson Chris C
Environmental and Life Sciences Graduate Program, Trent University, Peterborough, Ontario K9J 7B8, Canada.
Department of Biology, Trent University, Peterborough, Ontario K9L 0G2, Canada.
Conserv Physiol. 2021 Apr 24;9(1):coab021. doi: 10.1093/conphys/coab021. eCollection 2021.
The capacity of ectotherms to cope with rising temperatures associated with climate change is a significant conservation concern as the rate of warming is likely too rapid to allow for adaptative responses in many populations. Transgenerational plasticity (TGP), if present, could potentially buffer some of the negative impacts of warming on future generations. We examined TGP in lake trout to assess their inter-generational potential to cope with anticipated warming. We acclimated adult lake trout to cold (10°C) or warm (17°C) temperatures for several months, then bred them to produce offspring from parents within a temperature treatment (cold-acclimated and warm-acclimated parents) and between temperature treatments (i.e. reciprocal crosses). At the fry stage, offspring were also acclimated to cold (11°C) or warm (15°C) temperatures. Thermal performance was assessed by measuring their critical thermal maximum (CTM) and the change in metabolic rate during an acute temperature challenge. From this dataset, we also determined their resting and peak (highest achieved, thermally induced) metabolic rates. There was little variation in offspring CTM or peak metabolic rate, although cold-acclimated offspring from warm-acclimated parents exhibited elevated resting metabolic rates without a corresponding increase in mass or condition factor, suggesting that transgenerational effects can be detrimental when parent and offspring environments mismatch. These results suggest that the limited TGP in thermal performance of lake trout is unlikely to significantly influence population responses to projected increases in environmental temperatures.
外温动物应对与气候变化相关的气温上升的能力是一个重大的保护问题，因为变暖速度可能太快，许多种群无法做出适应性反应。如果存在跨代可塑性（TGP），则有可能缓冲变暖对后代的一些负面影响。我们研究了湖鳟的跨代可塑性，以评估它们应对预期变暖的代际潜力。我们将成年湖鳟在低温（10°C）或高温（17°C）下驯化几个月，然后让它们繁殖后代，这些后代来自同一温度处理组内的亲本（冷驯化和亲本和热驯化亲本）以及不同温度处理组之间（即正反交）。在鱼苗阶段，后代也被驯化到低温（11°C）或高温（15°C）。通过测量它们的临界热最大值（CTM）和急性温度挑战期间代谢率的变化来评估热性能。从这个数据集中，我们还确定了它们的静息代谢率和峰值（最高达到的、热诱导的）代谢率。后代的CTM或峰值代谢率几乎没有变化，尽管来自热驯化亲本的冷驯化后代表现出静息代谢率升高，但体重或条件因子没有相应增加，这表明当亲本和后代环境不匹配时，跨代效应可能是有害的。这些结果表明，湖鳟热性能的有限跨代可塑性不太可能显著影响种群对预计环境温度升高的反应。
