Whole-body endothermy in a mesopelagic fish, the opah, Lampris guttatus

@article{Wegner2015WholebodyEI,
  title={Whole-body endothermy in a mesopelagic fish, the opah, Lampris guttatus},
  author={Nicholas C. Wegner and Owyn E. Snodgrass and Heidi Dewar and John R. Hyde},
  journal={Science},
  year={2015},
  volume={348},
  pages={786 - 789}
}
A cold-water fish with a warm heart Mammals and birds warm their entire bodies above the ambient temperature. Generally, this ability is lacking in other vertebrates, although some highly active fish can temporarily warm their swim muscles. Wegner et al. show that the opah, a large deepwater fish, can generate heat with its swim muscles and use this heat to warm both its heart and brain. This ability increases its metabolic function in cold deep waters, which will help the fish compete with… 
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