Disappearing frogs - Kerry M. Kriger
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0:07 - 0:09Have you ever heard the sound of frogs
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0:09 - 0:10calling at night?
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0:10 - 0:12For hundreds of millions of years,
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0:12 - 0:15this croaking lullaby has filled the nighttime air.
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0:15 - 0:17But recent studies suggest
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0:17 - 0:18that these frogs are in danger
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0:18 - 0:20of playing their final note.
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0:20 - 0:22Over the past few decades,
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0:22 - 0:26amphibian populations have been rapidly disappearing worldwide.
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0:26 - 0:28Nearly one-third of the world's amphibian species
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0:28 - 0:30are endanger of extinction,
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0:30 - 0:33and over 100 species have already disappeared.
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0:33 - 0:35But don't worry, there's still hope.
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0:35 - 0:37Before we get into how to save the frogs,
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0:37 - 0:39let's start by taking a look
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0:39 - 0:40at why they're disappearing
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0:40 - 0:43and why it's important to keep them around.
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0:43 - 0:45Habitat destruction is the number one problem
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0:45 - 0:47for frog populations around the world.
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0:47 - 0:50There are seven billion humans on the planet,
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0:50 - 0:52and we compete with frogs for habitat.
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0:52 - 0:54We build cities, suburbs, and farms
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0:54 - 0:56on top of frog habitat
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0:56 - 0:57and chop forests
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0:57 - 0:58and drain the wetlands
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0:58 - 0:59that serve as home
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0:59 - 1:02for numerous amphibian populations.
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1:02 - 1:04Climate change alters precipitation levels,
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1:04 - 1:08drying up ponds, streams, and cloud forests.
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1:08 - 1:10As the Earth's human population continues to grow,
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1:10 - 1:13so will the threats amphibians face.
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1:13 - 1:15There are a variety of other factors
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1:15 - 1:17contributing to the frogs' decline.
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1:17 - 1:19Over-harvesting for the pet and food trade
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1:19 - 1:21results in millions of frogs
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1:21 - 1:23being taken out of the wild each year.
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1:23 - 1:24Invasive species,
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1:24 - 1:26such as non-native trout and crawfish,
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1:26 - 1:28eat native frogs.
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1:28 - 1:29Humans are facilitating the spread
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1:29 - 1:31of infectious diseases
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1:31 - 1:33by shipping over 100 million amphibians
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1:33 - 1:35around the world each year
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1:35 - 1:37for use as food, pets, bait,
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1:37 - 1:38and in laboratories and zoos,
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1:38 - 1:41with few regulations or quarantines.
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1:41 - 1:43One of these diseases,
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1:43 - 1:44chytridiomycosis,
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1:44 - 1:47has driven stream-dwelling amphibian populations
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1:47 - 1:48to extinction
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1:48 - 1:49in Africa,
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1:49 - 1:49Australia,
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1:49 - 1:50Europe,
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1:50 - 1:52and North, Central, and South America.
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1:52 - 1:54On top of all these problems,
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1:54 - 1:57we add hundreds of millions of kilograms of pesticides
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1:57 - 1:59to our ecosystems each year.
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1:59 - 2:01And these chemicals are easily absorbed
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2:01 - 2:03through amphibians' permeable skin,
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2:03 - 2:05causing immunosuppression,
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2:05 - 2:06or a weakened immune system,
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2:06 - 2:08and developmental deformities.
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2:09 - 2:11Okay, so why are these little green guys
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2:11 - 2:12worth keeping around?
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2:12 - 2:15Frogs are important for a multitude of reasons.
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2:15 - 2:17They're an integral part of the food web,
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2:17 - 2:19eating flies, ticks, mosquitoes,
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2:19 - 2:20and other disease vectors,
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2:20 - 2:23thus, protecting us against malaria,
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2:23 - 2:24dengue fever,
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2:24 - 2:25and other illnesses.
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2:25 - 2:27Tadpoles keep waterways clean
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2:27 - 2:28by feeding on algae,
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2:28 - 2:29reducing the demand
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2:29 - 2:31on our community's filtration systems
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2:31 - 2:34and keeping our cost of water low.
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2:34 - 2:36Frogs serve as a source of food
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2:36 - 2:39for birds, fish, snakes, dragonflies, and even monkeys.
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2:39 - 2:41When frogs disappear,
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2:41 - 2:42the food web is disturbed,
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2:42 - 2:45and other animals can disappear as well.
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2:45 - 2:47Amphibians are also extremely important
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2:47 - 2:49in human medicine.
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2:49 - 2:51Over ten percent of the Nobel prizes
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2:51 - 2:52in physiology and medicine
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2:52 - 2:53have gone to researchers
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2:53 - 2:56whose work depended on amphibians.
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2:56 - 2:58Some of the antimicrobial peptides
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2:58 - 3:00on frog skin can kill HIV,
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3:00 - 3:02some act as pain killers,
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3:02 - 3:05and others serve as natural mosquito repellents.
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3:05 - 3:07Many discoveries await us
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3:07 - 3:08if we can save the frogs,
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3:08 - 3:10but when a frog species disappears,
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3:10 - 3:12so does any promise it holds
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3:12 - 3:14for improving human health.
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3:14 - 3:16Fortunately, there are lots of ways you can help,
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3:16 - 3:18and the best place to start
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3:18 - 3:20is by improving your ecological footprint
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3:20 - 3:22and day-to-day actions.
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3:22 - 3:24The next time you listen to that nighttime lullaby,
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3:24 - 3:27don't think of it as just another background noise,
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3:27 - 3:28hear it as a call for help,
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3:28 - 3:31sung in perfect croaking harmony.
- Title:
- Disappearing frogs - Kerry M. Kriger
- Description:
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View full lesson: http://ed.ted.com/lessons/disappearing-frogs-kerry-m-kriger
Frogs (and amphibians in general) are in danger -- worldwide, nearly one-third of the world's amphibian species are on the verge of extinction. And yet, frogs contribute to our well-being in many important ways. Kerry M. Kriger describes why frogs are in trouble and how you can help save them.
Lesson by Kerry M. Kriger, animation by Simon Ampel.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TED-Ed
- Duration:
- 03:48
TED edited English subtitles for Disappearing frogs - Kerry M. Kriger | ||
Jessica Ruby approved English subtitles for Disappearing frogs - Kerry M. Kriger | ||
Jessica Ruby accepted English subtitles for Disappearing frogs - Kerry M. Kriger | ||
Jessica Ruby edited English subtitles for Disappearing frogs - Kerry M. Kriger | ||
Jessica Ruby edited English subtitles for Disappearing frogs - Kerry M. Kriger | ||
Andrea McDonough edited English subtitles for Disappearing frogs - Kerry M. Kriger | ||
Andrea McDonough edited English subtitles for Disappearing frogs - Kerry M. Kriger |