Eat now, pay later? Evidence of deferred food-processing costs in diving seals
Eat now, pay later? Evidence of deferred food-processing costs in diving seals
复制标题
现在吃，以后付钱吗？
作者：
Carol E. Sparling;M. Fedak;D. Thompson
海豹可能会推迟昂贵的生理过程（例如消化），这些过程与潜水的生理调整不相容，直到活跃的觅食期之后。我们提出了不寻常的配置文件的代谢率（MR）在灰海豹在长期模拟觅食旅行（4 - 5天），提供证据。我们测量了极高的MR（高达基线水平的近7倍）和高心率，在延长的表面间隔期间，海豹在表面上不动。这些最常发生在夜间，并经常发生在喂食结束后数小时。在这些事件中，高于基线水平的耗氧量和耗氧量的持续时间与进食量相关，证实了这些代谢高峰与当天早些时候觅食期间进食的食物加工有关。我们认为，这些时期的高MR代表了觅食过程中推迟的成本的回报。
Seals may delay costly physiological processes (e.g. digestion) that are incompatible with the physiological adjustments to diving until after periods of active foraging. We present unusual profiles of metabolic rate (MR) in grey seals measured during long-term simulation of foraging trips (4–5 days) that provide evidence for this. We measured extremely high MRs (up to almost seven times the baseline levels) and high heart rates during extended surface intervals, where the seals were motionless at the surface. These occurred most often during the night and occurred frequently many hours after the end of feeding bouts. The duration and amount of oxygen consumed above baseline levels during these events was correlated with the amount of food eaten, confirming that these metabolic peaks were related to the processing of food eaten during foraging periods earlier in the day. We suggest that these periods of high MR represent a payback of costs deferred during foraging.