But in fact, any big shell will do—such as a conch. With a few of its suckers, this octopus is holding two halves of a clamshell. As you watch, it drops them and hoists itself up a little.

More than a fanciful shark-octopus hybrid featured in low-budget ... "A large metallic grey dorsal fin signalled a big shark, a short-fin mako," Constantine wrote in the piece published March ...