Here’s a lovely bit of evolutionary trivia: Apparently our hiccups are caused because we’re descended from fish.

That’s the argument that Neil Shubin, head of the University of Chicago’s anatomy school, makes in his new book Your Inner Fish. As a review of the book notes:

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.

Love it. Shubin’s book is a nifty and subtle rebuttal to opponents of evolution, since he documents the often kooky ways in which DNA from far-back ancestors wound up inside us: “Fossil amphibian fins that demonstrate a structural affinity with human hands; teeth, first discovered in ancient jawless fish, that evolved into modern mammary and sweat glands; and genes, which control our eyes and ears, that correspond directly to DNA found in primitive jellyfish.” I think I’m going to buy a copy tomorrow.

(Photo courtesy ich_bin_ein_elmo’s Creative Commons Attribution Share-Alike license!)