This time on Shark Bites, Steve Backshall reveals the positively prehistoric sixgill shark. It has barely changed in 200 million years. Living in deep waters they are also incredibly hard to see, but Steve knows one spot off Canada's mainland where they occasionally come to shallower depths. Armed with a remote underwater camera and some smelly bait to lure it in, he tries to catch it on camera. These sharks earn their name from their sixth pair of gills and back in his Shark Lab Steve explains how this ancient adaptation may help them to survive in these extremes. Show less