Sharks, as you may have noticed, don’t normally swim on their backs, but a group on a cage-diving trip in Australia spotted a great white doing its best impression of the back stroke.
The strange footage was shot by Wendy Bower-Leech on a boat belonging to the Calypso Star Charters. According to the charter company, the shark is an untagged female measuring about 12 feet in length.
“It swam on its back for several seconds as depicted in the video but the shark was in the vicinity of our dive cage for a couple of hours much to the delight of our guests,” the spokesperson told Fox News over Facebook.
You may have heard of something that occurs in sharks called tonic immobility. In short, when a shark is flipped onto its back, it appears to become almost hypnotized.
While tonic immobility certainly did not occur in this particular shark, it’s unclear why, exactly, it was swimming upside down. One researcher does have a theory, though. “My guess is it was mouthing the boat to check it out and ended up unintentionally swimming on its back in the process, which can almost paralyze sharks,” said Molly Zaleski, a marine scientist based in Alaska, to IFLScience. “Sharks (and some other animals) have this reaction to being upside down called ‘tonic immobility’ that ’causes a temporary state of inactivity.'”
