I read an "8 fun facts about octopi" article that included the statement, "While octopi swim, this third heart doesn’t beat ...". The information on the two gill hearts was incorrectly stated but I wondered where this idea came from and found it in the Ten Curious Facts About Octopuses from the Smithsonian Science section. The author of the Care2 article clearly did not know anything about cephalopods and the Smithsonian article has some sketchy statements but does anyone know if the heart stopping while swimming has ANY validation? I had never heard it before and suspect it to be bunk but given the original source I am curious.