Humans are not the only species whose metabolism slows down with age

A study led by Duke University found that bottlenose dolphins burn more slowly with age, just like us

Rebecca Linbach, a postdoctoral postdoc in evolutionary anthropology at Duke University and first author, said that this is the first time scientists have measured age-related metabolic slowdowns in large species other than humans

Limbach studied energy expenditure and other physiological issues in animals ranging from mice to monkeys

"It is very tricky to get it back when you need it," Limbach said

The researchers studied 10 bottlenose dolphins between the ages of 10 and 45.

In order to measure their daily average metabolic rate, the researchers used the "double-labeled water method

Just like humans extend their arms when drawing blood, dolphins in these facilities will also actively lift their tail fins out of the water so that their caregivers can collect blood or urine as part of their regular inspections

By analyzing the levels of heavy hydrogen and heavy oxygen atoms in blood or urine, the research team was able to calculate how much carbon dioxide the dolphins produce every day, and thus how many calories they burn in their daily lives

Their discovery surprised them

Researchers predict that the metabolism of dolphins will accelerate, because dolphins are warm-blooded animals like humans, and maintaining body temperature in water requires more energy than in air

However, despite living in the ocean world, they found that bottlenose dolphins consume 17% less energy per day than marine mammals of their size

Scientists have also noticed some common signs of metabolic aging in humans

Limbach said that this is not because of lack of exercise

The dolphins in the study were observed tossing and spinning, walking with their tails, jumping out of the water, fast enough to wake up 6 to 18 times per hour, and they remained active in their 40s

But regardless of their activity level, the metabolic pattern remains the same

"It's not because they eat too much," Linbach said

Researchers say that this work can reveal factors that, in addition to diet and life>
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"Further research on this commonality between us and dolphins may help us understand why human metabolism slows down as we age," said Hannah Hannah, a graduate student in the laboratory of Professor Brian Hale at Duke University.
Salomon said
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Austin Allen, a co-author of the Duke University Marine Laboratory, said: "This research is only possible with healthy dolphins under the care of humans
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"We need more data, especially data on young dolphins, because we only observed 10 dolphins," Limbach said
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"But I think this is an exciting first study
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Rebecca Rimbach, Ahmad Amireh, Austin Allen, Brian Hare, Emily Guarino, Chana Kaufman, Hannah Salomons, Herman Pontzer.
Total energy expenditure of bottlenose dolphins (Tursiops truncatus) of different ages .
Journal of Experimental Biology , 2021; 224 (15) DOI : 10.
1242/jeb.
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