The truth about bats - Amy Wray

1,822,045 views ・ 2014-12-16

TED-Ed


Please double-click on the English subtitles below to play the video.

00:10
Flying through the night, I watch over this world,
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a silent guardian, a watchful protector, a dark knight, I'm...
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Okay, fine. So, I'm not Batman. I'm just a bat.
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But like Batman, I'm often misunderstood.
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People think I'm scary, strange and dangerous.
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If they only knew my story, though, I'd be cheered as a hero.
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When people think of bats,
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many think of vampires who want to suck their blood.
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But the truth is that out of over 1200 bat species,
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only three are vampire bats.
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Out of these three, only one prefers the blood of mammals,
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and even these bats mostly feed on cattle.
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Maybe that still doesn't seem so great,
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but vampire bats can be a great help to humans.
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01:00
A chemical known as desmoteplase found in vampire bat saliva
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helps break down blood clots,
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and is being tested by recovering stroke victims.
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Of the remaining 1000+ species of bats, about 70% feed on insects.
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These bats help control the real vampires:
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mosquitos, whose nasty bites are not just annoying
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but spread diseases, like West Nile virus.
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A single little brown bat can eat 1000 insects every hour,
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and a colony of Mexican free-tailed bats can eat several tons of moths
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in just one night.
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In the United States alone,
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bats provide an estimated 3.7 billion dollars worth
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of free pest control for farmers,
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which benefits everyone who eats the foods that they grow.
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Fruit bats, also called megabats because of their large size,
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are important for the role they play in plant pollination.
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By traveling between flowers while feeding on nectar and fruits,
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these bats transport the pollen and seeds that help plants reproduce.
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In Southeast Asia, for example,
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the cave nectar bat is the only pollinator of the durian fruit.
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Other bats pollinate peaches, bananas,
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and the agave plants that tequila is made from.
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Without them,
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many of our food plants would be unable to produce the tasty fruits we enjoy.
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As heroes of the ecosystem, bats have their own unique utility belts.
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Bats have been a source of inspiration for the design of flying robots
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and even an energy-efficient spy plane,
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as they are the only mammal capable of true powered flight.
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Echolocation, a type of biological sonar, is also used by bats as a way to navigate
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and find prey in the dark.
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Although there's a common misconception that bats are blind,
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in truth, all species of bats have sight.
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And some have even adapted large eyes to see better in dim lighting.
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Many people worry about getting infected by bats,
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and like any other animals, bats can carry diseases, like rabies.
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In reality, though, less than .5% of all bats carry this virus.
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That's about the same odds as getting the same result on a coin flip
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eight times in a row.
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The perception that bats are often diseased
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may come from the fact that sick bats,
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who may show unusual behavior, emerge during the daytime,
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or be unable to fly,
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are more likely to be encountered by people.
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So a good way to protect yourself is to protect bats as well,
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keeping them healthy, protecting their habitats,
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and reducing their risk of transmitting disease.
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In North America, bats are threatened by a devastating sickness
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called white-nose syndrome.
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This fungal infection causes bats to wake up
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while hibernating during a winter.
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Unable to find food, they expend large amounts of energy,
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and eventually starve to death.
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White-nose syndrome has wiped out entire caves full of bats,
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with a mortality rate that can exceed 90%.
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Climate change and habitat destruction
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also pose serious threats to bat populations.
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For example, in January 2014, a record heat wave in Australia
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caused over 100,000 bats to die from heat exhaustion.
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Some people just want to watch the world burn,
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and bats all over the world are threatened by damage to the places that we call home,
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including mangrove swamps,
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old-growth forests,
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and, of course, bat caves.
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So even though I'm the hero of the story, I do need to be saved.
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And now that you know the true story about us bats,
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you can learn how to protect such heroic animals.
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Install a properly designed bat box,
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one of the easiest ways to provide shelter for bats.
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Discourage the use of pesticides, which can harm bats
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when we try to feed on the insects you want to get rid of in the first place.
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Avoid going into caves where you might disturb hibernating bats,
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and always decontaminate your gear after visiting a cave.
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If you have unwanted bats living in an attic or barn,
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contact your local government to safely and humanely relocate us.
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And if you come across a bat, do not attempt to handle it,
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but instead, call Animal Control.
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Batman might want to keep his identity secret,
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but a great way to help real bats is by continuing to learn about them
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and spreading the truth that they are real heroes,
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even if their good deeds are often unseen.
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