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  • In the grasslands of Mauritania,

  • a gazelle suffering from tuberculosis takes its last breath.

  • Collapsing near a small pool,

  • the animal’s corpse threatens to infect the water.

  • But for the desert’s cleanup crew, this body isn’t a problem; it’s a feast.

  • Weighing up to 10 kilograms

  • and possessing a wingspan of nearly 3 meters,

  • the lappet-faced vulture is the undisputed king of the carcass.

  • This bird’s powerful beak and strong neck

  • easily tear through tough hide and muscle tissue,

  • opening entry points for weaker vultures to dig in.

  • This colossal competition is too dangerous for the tiny Egyptian vulture.

  • With a wingspan of only 180 centimeters,

  • this vulture migrated to Africa from his family nest in Portugal,

  • using thermal updrafts to stay aloft for hours at a time.

  • But upon arrival, he finds himself near the bottom of the pecking order.

  • Fortunately, what he lacks in size, he makes up for in intelligence.

  • A short distance away, he spots an unguarded ostrich nest,

  • full of immense, but impenetrable eggs.

  • Using a large rock, he smashes one open for a well-earned meal

  • though hell circle back to the gazelle once the larger birds are gone.

  • High above the commotion are Ruppell’s Griffon vultures.

  • Soaring at an altitude of over 11,000 meters,

  • these birds fly higher than any other animal.

  • At this height, they can’t see individual carcasses.

  • But the sight of their fellow vultures guides them to the feeding.

  • Their featherless heads help them regulate

  • the sudden rise in temperature as they descend

  • and keep them clean as they tear into the decaying gazelle.

  • The carcass is stripped clean in hours,

  • well before the rotting meat infects the water supply.

  • And the tuberculosis doesn’t stand a chance at infecting the vultures.

  • These birds have evolved the lowest gastric pH in the animal kingdom,

  • allowing them to digest diseased carrion and waste without becoming sick.

  • In fact, species like the mountain-dwelling bearded vulture

  • have stomachs so acidic,

  • they can digest most bones in just 24 hours.

  • This adaptation helps smaller vultures supplement their diet with dung,

  • while larger vultures can consume diseased meat up to 3 days old.

  • Their acidic stomachs protect them from living animals too:

  • their rancid vomit scares off most predators.

  • These stomachs of steel are essential to removing pathogens like cholera,

  • anthrax, and rabies from the African ecosystem.

  • But while vultures can easily digest natural waste,

  • man-made chemicals are another story.

  • Diclofenac, a common veterinary drug used to treat cattle in India,

  • is fatal to vultures.

  • And because local religious beliefs prohibit eating beef,

  • scavengers often consume cattle carcasses.

  • Since the 1990s, the drug,

  • along with threats from electricity pylons and habitat loss,

  • has contributed to a 95% decline in the region’s vulture population.

  • In nearby Africa, poachers intentionally poison carcasses

  • to prevent the birdspresence from alerting authorities to their location.

  • One poisoned carcass can kill over 500 vultures.

  • Today, more than 50% of all vulture species are endangered.

  • In regions where vultures have gone extinct,

  • corpses take three times longer to decay.

  • These carcasses contaminate drinking water,

  • while feral dogs and rats carry the diseases into human communities.

  • The Asian and African Vulture Crisis has led to an epidemic of rabies in India,

  • where infections kill roughly 20,000 people each year.

  • Fortunately, some communities have already realized how important vultures are.

  • Conservationists have successfully banned drugs like Diclofenac,

  • while other researchers are working to repopulate vulture communities

  • through breeding programs.

  • Some regions have even opened vulture restaurants

  • where farmers safely dispose of drug-free livestock.

  • With help, vultures will be able to continue their role

  • conserving the health of our planettransforming death and decay into life.

In the grasslands of Mauritania,

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B2 US TED-Ed vulture gazelle carcass digest tuberculosis

Vultures: The acid-puking, plague-busting heroes of the ecosystem - Kenny Coogan

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    shuting1215 posted on 2020/03/08
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