Anticipatory changes in organismal responses, triggered by reliable environmental cues for future conditions, are key to species’ persistence in temporally variable environments. Such responses were tested by measuring the physiological performance of a tropical high-shore oyster in tandem with the temporal predictability of environmental temperature. Heart rate of the oyster increased with environmental temperatures until body temperature reached ∼37°C, when a substantial depression occurred (∼60%) before recovery between ∼42° and 47°C, after which cardiac function collapsed. The sequential increase, depression, and recovery in cardiac performance aligned with temporal patterns in rock surface temperatures, where the risk of reaching temperatures close to the oysters’ lethal limit accelerates if the rock heats up beyond ∼37°C, coinciding closely with the body temperature at which the oysters initiate metabolic depression. The increase in body temperature over a critical threshold serves as an early-warning cue to initiate anticipatory shifts in physiology and energy conservation before severe thermal stress occurs on the shore. Cross-correlating the onset of physiological mechanisms and temporal structures in environmental temperatures, therefore, reveals the potential role of reliable real-time environmental cues for future conditions in driving the evolution of anticipatory responses.

中文翻译：

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定时代谢性抑郁：预测潮间带极端环境中的热应力。

由对未来状况的可靠环境暗示引发的生物反应的预期变化，是物种在时变环境中持久存在的关键。通过测量热带高海岸牡蛎的生理性能和环境温度的时间可预测性来测试这种反应。牡蛎心率会随着环境温度的升高而升高，直到体温达到约37°C（约60％），然后在约42°C至47°C的温度范围内恢复之前，出现了严重的抑郁感，随后心功能崩溃。随着岩石表面温度的升高，情绪下降的顺序性增加，下降和恢复与岩石表面温度的时间规律一致，如果岩石加热到约37°C以上，则达到接近牡蛎致死极限的温度的风险会加快，与牡蛎引发代谢抑制的体温非常吻合。体温升高超过临界阈值可作为预警信号，以在海岸上发生严重的热应力之前启动生理和能量守恒的预期变化。因此，将相互关联的生理机制和时间结构在环境温度下的发作揭示了可靠的实时环境线索对未来状况的潜在作用，可以推动预期反应的发展。