mammalian diving reflex

biology

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Last updated

June 30, 2026

Quick Summary

The mammalian diving reflex is a biological response that helps vertebrates, including humans, conserve oxygen during dives into water. This reflex is particularly powerful in children and involves diverting blood from the limbs and surface areas to the heart and brain. It also causes a temporary halt in breathing efforts and slows the heart rate.12

While humans are not naturally adapted for aquatic life, vestiges of this reflex persist, enhancing survival during submersion. This mechanism allows for a reduced metabolic need for oxygen, enabling the brain to function on stored oxygen despite the absence of breathing. This reflex is a key adaptation for marine mammals that hunt underwater for extended periods.12

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drowning
…cold water, known as the mammalian diving reflex, enhances survival during submersion, thus permitting seagoing mammals to hunt for long periods underwater. Scientists have recently determined that vestiges of the reflex persist in humans. The mechanism is powerful in children. It diverts blood from the limbs, abdomen, and surface areas…
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…cold water, known as the mammalian diving reflex, enhances survival during submersion, thus permitting seagoing mammals to hunt for long periods underwater. Scientists have recently determined that vestiges of the reflex persist in humans. The mechanism is powerful in children. It diverts blood from the limbs, abdomen, and surface areas…
Read More