Researchers learn why king snakes reign over constrictors

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A pair of scientists, including a biologist from the 青青草视频, has countered a long-held theory that king snakes suffocate their prey.

UL Lafayette鈥檚 Dr. Brad Moon and Dr. David Penning, a biologist at Missouri Southern State University, have tested how the snakes overcome their victims. Penning is a former UL Lafayette doctoral student.

King snakes are native to North America and have evolved into the strongest constrictors in the world, with the ability to exert 180 mm Hg of pressure. That鈥檚 about 60 mm Hg higher than the healthy blood pressure of a human being.

With such force, king snakes aren鈥檛 taking their victims鈥 breath away. They鈥檙e restricting blood flow鈥攁nd that鈥檚 a major breakthrough in how scientists understand the relationship between predator and prey in the reptile world.

Moon and Penning鈥檚 conclusions are featured in this month鈥檚 edition of the Journal of Experimental Biology. Their study also received attention last week from National Geographic.

The king snake鈥檚 ability to cut off blood flow in its victims has given the reptile something of an arrogance in the wild, the researchers concluded. The snake has ceased to play by the old rules that say a smaller predator avoids a larger prey.

In fact, a king snake can use its killer squeeze to neutralize and eat other snakes up to 20 percent larger in size.

When the scientists matched a king snake versus a rat snake, the smaller king snake picked a fight, Penning told National Geographic. 鈥淭hey actively and directly will attack a larger individual. That鈥檚 not normally what鈥檚 expected across basically all of animal diversity.鈥

The constrictor study isn鈥檛 the first time Moon and Penning have proven a perennial theory about snakes incorrect鈥攁nd received national publicity for it. A study they conducted last year showed that venomous rattlesnakes and other vipers do not, as previously thought, strike faster than their nonvenomous brethren.

UL Lafayette doctoral student Baxter Sawvel also collaborated on the project, which received notice from National Geographic, the Los Angeles Times, The New York Times and Discover, among other publications.

Read more about Moon and Penning鈥檚 latest conclusions at