Neil Shubin's new book, Your Inner Fish, traces the evolutionary history of the human body's many quirks, including the origin of the hiccup:
Or consider hiccups. Spasms in our diaphragms, hiccups are triggered by electric signals generated in the brain stem. Amphibian brain stems emit similar signals, which control the regular motion of their gills. Our brain stems, inherited from amphibian ancestors, still spurt out odd signals producing hiccups that are, according to Shubin, essentially the same phenomenon as gill breathing. Similarly, modern lifestyles leave us vulnerable to predispositions to obesity, heart attacks and haemorrhoids because we have the genes of hunter-gatherers who lived active, not sedentary, lives.
My kid's got persistent hiccups (they started in the womb) and while they don't seem to bother her, they take some getting used to for visitors. Now I can just explain that she's getting in touch with her inner amphibian.
Link, Link to Your Inner Fish on Amazon
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