Lipińska Anna M, Adamski Paweł, Ćmiel Adam M, Golab Maria J, Idczak-Figiel Paulina A, Lopes-Lima Manuel, Mageroy Jon H, Nowakowska Anna, Österling Martin, Sniegula Szymon, Teixeira Amílcar, Costa Silvana, Varandas Simone, Halabowski Dariusz
Institute of Nature Conservation, Polish Academy of Sciences, al. Adama Mickiewicza 33, 31-120, Kraków, Poland.
Academia Copernicana, Department of Animal Physiology and Neurobiology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Torun, Poland.
Sci Rep. 2025 Jul 1;15(1):22232. doi: 10.1038/s41598-025-06450-7.
Freshwater mussels across Europe exhibit physiological and behavioural adaptations to survive winter conditions. Climate change projections, including more frequent extreme weather events, are expected to intensify pressures on these ecosystems. In this study, we tested the temperature-size hypothesis, which posits that larger body size in ectothermic organisms is an adaptation to colder climates. We predicted that Anodonta anatina populations in northern regions would have larger shells than those in central and southern regions. Additionally, we hypothesised that harsher winters in northern regions require mussels to maintain higher glycogen levels as an energy reserve. We also explored whether shell size varies between lowland and upland populations, following the temperature-size rule, and whether supercooling (SCP) occurs primarily in northern populations as a complementary survival strategy. Northern populations had the highest glycogen levels, reflecting adaptations to colder conditions. SCP was rare (2.5%) and observed predominantly in northern mussels, suggesting limited reliance on freeze avoidance. Instead, it is likely that mussels employ mixed strategies, such as metabolic reduction and burrowing, to withstand winter. These findings link shell size, glycogen levels, and SCP to specific survival strategies, providing new insights into the cold tolerance mechanisms of freshwater mussels and their potential vulnerability to climate change.
欧洲各地的淡水贻贝展现出生理和行为上的适应性以度过冬季。气候变化预测，包括更频繁的极端天气事件，预计会加剧这些生态系统所面临的压力。在本研究中，我们测试了温度-体型假说，该假说认为变温生物体型较大是对寒冷气候的一种适应。我们预测北部地区的无齿蚌种群的贝壳会比中部和南部地区的更大。此外，我们假设北部地区更严酷的冬季要求贻贝维持更高的糖原水平作为能量储备。我们还依据温度-体型规则探究了低地和高地种群之间贝壳大小是否存在差异，以及过冷现象（SCP）是否主要发生在北部种群中作为一种补充性生存策略。北部种群的糖原水平最高，这反映了对寒冷条件的适应。过冷现象很罕见（2.5%），且主要在北部贻贝中观察到，这表明对避免结冰的依赖有限。相反，贻贝很可能采用诸如代谢降低和挖掘等混合策略来抵御冬季。这些发现将贝壳大小、糖原水平和过冷现象与特定的生存策略联系起来，为淡水贻贝的耐寒机制及其对气候变化的潜在脆弱性提供了新的见解。
