Source: D4K: “Snakes”
Visit the D4K companion Web site to learn more about Snakes. D4K: “Snakes”
This video segment from IdahoPTV's D4K looks at the unique natural history and adaptations of snakes. How do they move? How do they hear without any ears? How do they move without any arms or legs? Learn about scales, forked tongues, venom, cold-bloodedness and the various ways they kill their prey.
JOAN: There are over 2500 different types of snakes in the world. Snakes are reptiles. They're cold blooded. That means a snake's body temperature depends upon the temperature of where it lives. So snakes like to keep warm by absorbing heat from sun-soaked rocks or from the ground or they hide under rock piles or low lying plants to stay cool.
[CHILD] Snakes have scales covering their skin. The scales protect their bodies like armor. The scales also help keep moisture inside their bodies so they don't dry out in the sun.
[JOAN] Snakes travel in different ways. Most commonly a snake moves by pushing one side of its body and then the other against rocks or bumps on the ground. It can also use its scales to help get some traction.
Snakes don't have eyelids. Instead, snakes have a clear scale protecting their eyes. That's why they always look like they're staring. Snakes don't have ears like we do but are very good at detecting vibrations. And snakes have special smell detectors in their mouth that can pick up the scents in the air with their forked tongue.
[CHILD] Snakes are predators. They eat their food whole. They have special jaws that allow them to open their mouths really wide.
[JOAN] Snakes usually lie in wait and then quickly strike and grab their prey. Some snakes like boas squeeze their prey to death and some snakes inject venom to kill their prey. Rattlesnakes are the best known of the venomous snakes here in the Americas. When a rattlesnake senses danger they make a loud noise with the rattles at the end of their tails.
[RATTLESNAKE TAIL] [RATTLE, RATTLE, RATTLE]
It's a warning to stay away. Though most snakes are harmless, you never know so don't bother snakes in the wild.
[CHILD] But snakes you buy at the pet store can make good pets.[JOAN]
Just be sure you know how to care for them properly and that you want to do it for a long time because some snakes can live as long as 20 years.
Many people are afraid of snakes. Don't be. Snakes play an important role in nature. They eat a lot of things we think of as pests so without them we'd be in trouble.
Snakes live in almost every part of the world. A few types of snakes are endangered because we're destroying their habitat or killing them off. So respect snakes. Don't bother them in the wild and appreciate their role in the balance of nature.
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