Dr. Steve Palumbi studies the genetics, evolution, conservation, population biology and systematics of a diverse array of marine organisms. Along with Tony Palumbi he is the author of the forthcoming book The Extreme Life of the Sea. UnShark Week is a week long celebration of the ocean’s extremes.
Since 1987, the Discovery Channel’s annual Shark Week pumps up the thrill of encountering a dangerous shark. Teeth, danger, lunging predation, more teeth: this is what the week is mostly about. But most of the extreme species in the sea are not sharks. Sharks are not the biggest, the deepest, the fastest, even the deadliest. This week is exactly midway between Shark Weeks, 26 weeks till the next one; 26 weeks since the last. And because there are so many other thrilling species in the sea, we declare this week as UnShark Week – and dedicate it to the truly extreme animals in the ocean.
The fastest fish in the sea is not a shark. Sailfish have the unofficial record at 60 mph, and well documented speed trails have clocked tuna and wahoo at nearly 50 mph. By contrast the most celebrated human swimmers manage 6-7 mph. Billfish like marlin and sailfish feed at such high speeds that their brains and eyes can not operate fast enough. So as an adaptation to speed, these fish have evolved heaters in the brains and eyes so they can form and process images fast enough to snap up prey in high velocity sorties.