"Scientists have discovered how prized bluefin tuna keep their hearts pumping during temperature changes that would stop a human heart. The research helps to answer important questions about how animals react to rapid temperature changes, knowledge that's becoming more essential as the earth warms. Pacific bluefin tuna are top predators renowned for their epic migrations across the Pacific Ocean. They are also unique amongst bony fish as they are warm bodied (endothermic) and are capable of elevating their core body temperature up to 20°C above that of the surrounding water. They are also capable of diving down below 1000 m into much colder water which affects the temperature of their heart." - How tuna stay warm with cold hearts, February 5, 2015, Manchester University
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