This is a remarkably endearing and educational video. Mark Rober taught us many interesting facts about octopi. The plural can also also be octopuses. He did point out that their blue blood is copper-based, and that they have three hearts. What he didn’t mention is that all three hearts beat with independent rhythms. Among their many defenses, such as camouflage and squirting water out of their jet to swim away very quickly, is the ability to squirt a cloud of ink, thereby obscuring their view from enemies. The largest octopi, living off the coast of Washington State on the west coast of the United States, have been known to grow to beyond 30 feet across (9.1 meters) and weigh as much as 600 pounds (272 kg) Their eyes can be as big as 15 inches (38cm) in diameter.