Portal:Sharks/Did you know/6

... that the taillight shark has a gland on its belly that releases clouds of luminescent blue fluid?
...that the Jersey Shore shark attacks of 1916 killed four people and inspired Peter Benchley's novel Jaws (1974)?
... that the presence of the rare bigeye sand tiger in the Pacific Ocean was first suspected based on teeth recovered from the ocean floor?
... that the rough skin of the nursehound was once used as an abrasive called "rubskin", which cost a hundred times more than sandpaper?
... that the epaulette shark can survive for an hour without oxygen?