Data from: Metabolic costs imposed by hydrostatic pressure constrain bathymetric range in the lithodid crab Lithodes maja

Changing climate is shifting the distributions of marine species, yet the potential for shifts in depth distributions is virtually unexplored. Hydrostatic pressure is proposed to contribute to a physiological bottleneck constraining depth range extension in shallow-water taxa. However, bathymetric limitation by hydrostatic pressure remains undemonstrated, and the mechanism limiting hyperbaric tolerance remains hypothetical. Here, we assess the effects of hydrostatic pressure in the lithodid crab Lithodes maja (bathymetric range 4-790 m depth, approximately equivalent to 0.1 to 7.9 MPa hydrostatic pressure). Heart rate decreased with increasing hydrostatic pressure, and was significantly lower at ≥10.0 MPa than at 0.1 MPa. Oxygen consumption increased with increasing hydrostatic pressure to 12.5 MPa, before decreasing as hydrostatic pressure increased to 20.0 MPa: oxygen consumption was significantly higher at 7.5-17.5 MPa than at 0.1 MPa. Increases in expression of genes associated with neurotransmission, metabolism and stress were observed between 7.5 and 12.5 MPa. We suggest that hyperbaric tolerance in L. maja may be oxygen-limited by hyperbaric effects on heart rate and metabolic rate, but that L. maja’s bathymetric range is limited by metabolic costs imposed by the effects of high hydrostatic pressure. These results advocate including hydrostatic pressure in a complex model of environmental tolerance, where energy-limitation constrains biogeographic range, and facilitate incorporating hydrostatic pressure into the broader metabolic framework for ecology and evolution. Such an approach is crucial for accurately projecting biogeographic responses to changing climate, and for understanding the ecology and evolution of life at depth.气候变化正引发海洋物种分布范围的变迁，但目前学界几乎尚未系统探究海洋物种沿深度梯度的分布迁移潜力。有研究指出，静水压力（hydrostatic pressure）或为限制浅海类群深度分布范围扩张的生理瓶颈。然而，静水压力对物种分布水深的限制作用尚未得到实验证实，而制约高压耐受性的内在机制仍仅为假说。本研究以石蟹科莫氏石蟹（Lithodes maja）为研究对象，该物种的水深分布范围为4~790米，对应静水压力约0.1~7.9 MPa，以此评估静水压力对其的影响。受试个体的心率随静水压力升高呈下降趋势，且当静水压力≥10.0 MPa时，心率显著低于0.1 MPa对照组。耗氧量随静水压力升高至12.5 MPa时逐步上升，随后随压力进一步升高至20.0 MPa而下降；在7.5~17.5 MPa的压力区间内，受试个体的耗氧量显著高于0.1 MPa对照组。在7.5~12.5 MPa的压力区间内，研究人员观测到与神经传递、代谢及应激反应相关的基因表达量显著上调。本研究认为，莫氏石蟹的高压耐受性或受高压对心率及代谢速率产生的供氧约束，而其水深分布范围则受高静水压力引发的代谢成本限制。本研究结果表明，需将静水压力纳入“能量限制约束生物地理分布”的环境耐受性综合模型中，并推动静水压力被纳入生态与进化研究的广义代谢框架。该研究思路对于精准预测气候变化下的生物地理响应，以及理解深海生命的生态与进化过程均具有至关重要的意义。