The sound of a hiccup echoes back to our very distant past as fish and amphibians some 375 million years ago, Shubin said. It's really just a spasm that causes a sharp intake of breath followed by a quick partial closing of our upper airway with that flap of skin known as the glottis. It's best if you can nip it in the first couple of hics, he said.
It's much harder to stop once you've let yourself get up to 10. By that point, you've reverted to an ancient breathing pattern orchestrated by the brain stem that once helped amphibians breath, letting water pass the gills without leaking into the lungs. "Tadpoles normally breathe with something like a hiccup," Shubin said.
Can't wait until the book comes.