Brad Moon/Univ. of Louisiana at Lafayette
This could be embarrassing for rattlesnakes and other vipers: Their long-standing reputation as the snakes with the fastest strikes on Earth just got bit by the common Texas rat snake.
In lab tests biting a stuffed glove, Western rattlesnakes averaged speeds of 2.95 meters per second and Western cottonmouths averaged 2.98 m/s, says functional morphologist David Penning of the University of Louisiana at Lafayette. But Texas rat snakes, familiar farmyard chasers of pest rodents, averaged 2.67 m/s. Statistically that’s a three-way tie, Penning and his colleagues report March 16 in Biology Letters.
Strikes were over quickly but all species subjected their brains to impressive acceleration. Rat snakes accelerated their head more on average (190 meters per second2)
Penning’s point is not that vipers are slow, but that other snakes also evolved a lightning strike. “They have to eat too,” he says. Startled mammals have been clocked activating a muscle in as little as 14 to 151 milliseconds. Snakes in Penning’s tests reached their targets in 50 to 90 milliseconds, literally before some creatures could move a muscle. And if you blink — for a human average of 220 milleseconds — you miss it all.