The video below is of lunch — lunch for an American tourist in Hokadate, Hokkaido, Japan. The dish is called odori-don, and, as presented below, features a dead squid (dismembered from its brain) sitting atop a bed of rice, salmon roe, and seaweed. To demonstrate that the squid is fresh (most likely), the restaurant presents it in a stomach-turning way, at least to Westerners. They pour soy sauce over the squid’s legs — and the squid, dead, dances, as seen below (although you may just want to take our word for it).
What’s causing this to happen? Is the squid actually alive?
Rest assured, the squid is dead — just recently so. In fact, the same thing happens to frog legs, as seen here — and there is clearly no brain present. Rather, the squid’s cells still contain some unused adenosine triphosphate (or ATP), which powers muscular contraction and expansion and, therefore, movement. But ATP can’t simply act on its own accord — it needs something to make it go. Typically, that’s provided by the central nervous system, which, through electrical impulses, causes the ATP to do its thing. With no brain involved, the ATP just sits dormant, and, over time, dissipates, as the now-dying cell fails to create new ATP.
But the soy sauce makes the typical atypical. Soy sauce contains sodium and potassium. The sodium and potassium ions together work as a trigger of sorts, causing the ATP to contract and expand the muscles. The result: a dead, dancing squid headlining (and, perhaps, ruining) your meal.
From the Archives: Sounds From the Deep: The bonus fact is about squids.
Related: After watching the video above, it boggles the mind how this has 28 reviews (averaging five stars!).