Venomous snake

Venomous snakes are special kinds of snakes that can make a poisonous liquid called venom. They use this venom to catch their food, protect themselves, and help their bodies break down what they eat. This venom is usually shot out through their hollow or grooved teeth, called fangs.

Some well-known groups of venomous snakes include the Elapidae, Viperidae, Atractaspididae, and a few from the Colubridae family. There are about 600 different kinds of venomous snakes around the world.

The danger of a venomous snake to people depends on several things. It includes how likely the snake is to bite, how much venom it puts out, how well it can deliver the venom, and where on the body a bite happens. Snake venom can affect nerves and blood, making it very important to know about these snakes for safety.

Evolution

Main article: Evolution of snake venom

Venomous snakes have been around for about 28 million years. Their venom is a special kind of saliva that helps them catch prey and protect themselves. This venom is often shot out through special teeth called fangs right into the target. Recent studies support the Toxicofera hypothesis, suggesting that all snakes, and even some lizard families, may have had a small amount of toxic saliva in their ancestors. Over time, this developed into the powerful venom seen in some snake families through parallel evolution.

Taxonomy

There isn’t a special group just for venomous snakes. Many different families of snakes have venom. Scientists think venom may have developed in snakes more than one time. About one in four snake species are known to be venomous.

Terminology

Venomous snakes are sometimes called poisonous, but poison and venom are different. Poisons need to be eaten, breathed in, or absorbed to work, while venom is injected into the body. A few snakes are actually poisonous. Keelback snakes are both venomous and poisonous – they store poisons in special glands and get these toxins from eating poisonous toads. Also, some garter snakes from Oregon can keep toxins in their livers after eating rough-skinned newts.

Danger

Venomous snakes produce venom to catch their food, protect themselves, and help digest what they eat. This venom is usually shot into their prey using special teeth called fangs. Some snakes have well-developed fangs, while others do not.

The danger of a venomous snake can be measured by testing how much venom it takes to harm small animals like mice. This helps scientists understand which snakes might be more dangerous. However, this is not the only factor. Some very venomous snakes, like the inland taipan, are shy and rarely attack people. On the other hand, some snakes that live closer to people, like India's Big Four—the Indian cobra, common krait, Russell’s viper, and saw-scaled viper—are more likely to bite humans and cause harm.