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We get it, not everyone loves snakes.
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You may not want to encounter one in the wild.
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To each their own!
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That's why we're here, to take you on a world tour
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of some of nature's most incredible snakes from the safety of your home—
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and with your very own intrepid guide.
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All the snakes we'll be visiting belong to a group called the vipers.
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As of 2021, there are 368 species of viper worldwide.
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The name comes from the term viviparity, which means giving birth to live young.
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Unlike most snakes, which lay eggs,
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most vipers have eggs that hatch inside the mother,
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who then gives birth to up to dozens of tiny snakes.
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Not glad you're safe at home yet?
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Vipers are also often highly venomous,
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with two hollow fangs that fold flat to the roofs of their mouths.
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This allows the fangs to be extra long,
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unfolding into imposing weapons when the viper prepares to strike.
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So how about we pay them a surprise visit?
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First stop: the southeastern United States,
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where we can hear the viper before we can see it.
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The eastern diamondback rattlesnake is the largest of 36 species of rattlesnake.
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Rattlesnakes can shake their rattles up to 90 times per second
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to warn off predators for hours if needed.
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The rattle consists of hollow, interlocked segments made of keratin,
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the same substance that makes our nails and hair.
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When the snake shakes its tail, these segments hit each other,
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creating a shockingly loud noise.
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Now onto the mountains of western Iran, where a spider crawls across a rock,
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making easy prey for a passing bird— or not.
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The spider-tailed horned viper is perfectly camouflaged, almost invisible,
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except for its unique bulbous tail-tip with long drooping scales
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that look like a leggy spider.
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Spider-tailed vipers are only about 50 centimeters long,
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so they can lure small birds within striking range
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without compromising their ability to squeeze into narrow rock crevices.
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In the rainforests of Latin America lives a viper
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that couldn't be more different from the spider-tailed viper—
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if you can find it.
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It's one of the most elusive snakes in the world:
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the bushmaster.
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The bushmaster is a pit viper.
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Between each eye and nostril, it has a heat-sensing pit
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with a membrane covered in highly sensitive receptors
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that respond to temperature changes
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as small as one one-thousandth of a degree Celsius.
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These pits gather infrared information that is integrated with visual information
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in the optic tectum.
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This allows the bushmaster to “see” the heat signature
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of approaching prey or predators,
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helping it decide whether or not to strike and strike more accurately.
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This comes in handy for guarding a nest—
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unlike most other vipers, the bushmaster lays eggs
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in hollowed out tree buttresses or burrows made by other animals.
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It must be large enough to defend its nest—
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in fact, the bushmaster is the largest viper in the world,
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reaching lengths of over 11 feet, with huge fangs and deadly venom.
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Meanwhile, in the forests of sub-Saharan Africa,
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there's a shorter, chunkier viper that's even more venomous than the bushmaster.
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The African Gaboon viper has the longest fangs of any snake—
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yes, all 3,879 snake species, not just vipers—
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and can deliver 1,000 milligrams of venom in a single bite—
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enough to kill ten adult humans.
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Although deadly, Gaboon vipers have a reputation
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for being slow-moving and placid creatures.
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When they do strike, they hold onto their rodent prey while the venom takes effect,
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then quickly swallow it down.
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At this point, you may be worrying about our guide— but never fear,
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rodents like our little desert kangaroo rat have their own skills
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to evade the serpent's tooth.
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They stomp their feet at rattlesnakes, kick sand towards them,
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and evade their strikes with acrobatic leaps and powerful kicks—
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helping them live to guide another snake tour.