Stripy "alien" sharks have been filmed mating in extremely rare footage captured as part of Discovery's Shark Week. The footage shows two pyjama sharks (Poroderma africanum) as they coil around one another and sink to the seafloor, before parting ways. It's likely the first time this species has ever been filmed mating.
In "Alien Sharks: Strange New Worlds," biologist and adventurer Forrest Galante explores some of South Africa's lesser known species of shark, many of which haven't outwardly changed for millions of years.
