A clash of true oceanic titans fought in the remote crystal-blue battlefields of Ascension Island. Both apex predators, yet to these Mako and Tiger sharks, yellow-fin tuna are the ultimate prize.  In one corner, we have the enormous yellowfin tuna. This super fish is nearly twice the length of man and as heavy as a horse, yet it’s one of the fastest fish in the ocean. There is little that can keep up with this turbo-charged fish. In the other corner, we have the Galapagos shark, who knows this terrain like the back of its fins. With the tuna giving off an oily scent, the shark’s incredible sense of smell could give it the edge...