Why We Were Totally Wrong About How Boa Constrictors Kill
Conventional wisdom held that pythons and anacondas suffocate their prey. Instead, the predators cut off their victims' blood supply, a new study says.
But a new study reveals that these big, non-venomous serpents, found in tropical Central and South America, subdue their quarry with a much quicker method: Cutting off their blood supply.
When a boa tightens its body around its prey, it throws off the finely tuned plumbing of the victim's circulatory system. Arterial pressures plummet, venous pressures soar, and blood vessels begin to close. (Read how snakes know when to stop squeezing their prey.)
"The heart literally doesn't have enough strength to push against the pressure," says study leader Scott Boback, a vertebrate ecologist at Dickinson College in Carlisle, Pennsylvania.
Most animals can actually survive a relatively long time without breathing: Think about drowning people who are later resuscitated, he says. But
