Boa Constrictors found to sense heartbeats
The Boa Constrictor's signature method of killing their prey by wrapping their bodies around a target and squeezing it to death has been demonstrated to be informed by knowledge of the victim's heartbeat. The findings of the research team at Dickinson College in Pennsylvania led by Dr Scott Boback are reported in the Royal Society Journal Biology Letters.
Boa Constrictors can grow up to four metres long, have been known to live for up to 30 years, and hunt a broad variety of prey that includes rodents, wild pigs and even monkeys. The ability to track the prey's heartbeat allows the snake to balance its need for food against the expenditure of energy required to complete the kill, thus preventing energy wastage after incapacitation has been achieved.
Dr Boback's team implanted 'simulated hearts' of water-filled bulbs in dead rats and rigged a small pump that simulated the action of a heart beat. While the fake hearts were kept beating "the boas constricted rats... longer than any previous observation of a snake constricting a prey item - live or dead". However, the snakes reacted differently to the rats when the pumps were turned off – the snakes would 'strike, form their coils, constrict the rat, then gradually ease off".
This previously unknown ability suggests that Boa Constrictors are "capable of things that we did not realise before". The team speculate that the "snakes may utilise this acute tactile sense to coordinate complex movements associated with limbless locomotion."