Although I have been chasing them with rod and line since 1971, sharks have only once ever terrified me. I was wading a shallow lagoon alone in Christmas Island, off the settlement of Banana (‘population 666’ the sign ominously boasts), when I was surrounded by six prowling reef predators. Elephants kill more people each year than sharks do, but right then there were no elephants in sight. Short of performing the Indian rope trick up my fishing rod, there was nothing for it but to fend these critters off with blows from my water bottle until the launch arrived – mind you, I did manage to clock up my most recherché byline when later recounting my adventures in the Journal of the Kiribati and Tuvalu Philatelic Society.

Papa Hemingway liked to tattoo his initials on them with bullets; the Hawaiians worshipped them as gods. Most folks regard the Selachii with mixed feelings. They are hydrodynamically splendid, but do occasionally eat humans. Their stomach contents