Constrictors are snakes that squeeze their victims to death, rather than poisoning them. They include pythons, boas and anacondas.
A constrictor does not crush its victim. Instead, it winds itself around, gradually tightening its coils until the victim suffocates.
Constrictors usually swallow victims whole, then spend days digesting them. They have special jaws that allow their mouths to open very wide. A large meal can be seen as a lump moving down the body.
Pythons are tropical snakes that live in moist forests in Asia and Africa. They are the world’s biggest snakes, rivaled only by giant anacondas. Pythons are one long tube of muscle, well able to squeeze even big victims to death. They usually eat animals about the size of domestic cats, but occasionally they go for really big meals such as wild pigs and deer.
Pythons are big snakes that live in Asia, Indonesia and Africa. In captivity, reticulated pythons grow to 9 m. Boas and anacondas are the big constrictors of South America.
Boas capture their prey by lying in wait, hiding motionless under trees and waiting for victims to pass by. But like all snakes, they can go for many weeks without eating.
Like many snakes, most constrictors begin life as eggs. Unusually for snakes, female pythons look after their eggs until they hatch by coiling around them. Even more unusually, Indian and green tree pythons actually keep their eggs warm by shivering.
Female boas do not lay eggs, giving birth to live young.
Boas have tiny remnants of back legs, called spurs, which males use to tickle females during mating.
Anacondas spend much of their lives in swampy ground or shallow water, lying in wait for victims to come and drink. One anaconda was seen to swallow a 2 m-long caiman (a kind of crocodile).
When frightened, the royal python of Africa coils itself into a tight ball, which is why it is sometimes called the ball python. Rubber boas do the same, but hide their heads and stick their tails out aggressively to fool attackers.