Snakes sense prey's fading heartbeat

London, Jan 18 (ANI): Scientists have found that Boa constrictor snakes can sense their prey's heartbeat, and let go only when it stops.

Boa constrictors have a drawn-out method of subduing their prey - wrapping their muscular bodies around it and slowly squeezing it to death.

The research team, led by Dr Scott Boback from Dickinson College in the US state of Pennsylvania, wanted to find out if the snakes were able to "measure" the amount of time they needed to keep squeezing.

The scientists used rats to entice their captive Boa constrictor to attack.

But the team did not subject the rodents to death by constriction, instead implanting dead rats with "simulated hearts" - water-filled bulbs connected to a pump, which replicated the blood-pumping action of a live rat's heart.

When the snake struck out at one of the already-dead prey, the scientists were able to control this "fake heart" remotely.

They also used pressure sensors on the rat's bodies to measure how the snake adjusted its squeeze.

The snakes only released their prey when the heartbeat was stopped.

When the scientists kept the simulated heart pumping, they found that "the Boas constricted rats... longer than any previous observation of a snake constricting a prey item - live or dead".

"During constriction a snake actually 'feels' the heartbeat of their prey," the BBC quoted the researchers as saying.

"Many of us think of snakes as audacious killers, incapable of the complex functions we typically reserve for 'higher' vertebrates.

"We found otherwise and suggest that this remarkable sensitivity was a key advancement that forged the success of the entire snake group," they added.he findings are reported in the Royal Society journal Biology Letters. (ANI)