Hiccups are at least as intriguing as they are inconvenient. These noisy gulps and/or belches induced by involuntary contractions of the diaphragm seem to be far from useful in adults, but there’s evidence that they serve to help expel air from the stomach in suckling infant mammals.
Indeed, we get hiccups less often as we age. They might have truly ancient evolutionary origins. A hiccup-like reflex enables tadpoles to divert water to the gills and air to the lungs as they transition to air-breathing adults – just as our piscine ancestors would have had to do on the way to conquering the land.
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