
Under water a baby stops breathing for a few seconds, eyes open, the top of the lungs is sealed off, some water enters the stomach. So the baby can stay in the water for only a couple of seconds. Note the coordinated swimming movements which can propel him to over a meter. Diving baby’s: The Human Body, part 3; 1998 (BBC).
The diving reflex deals with the oxygen saving mode to maximize the time that can be spent under water.
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