9:59:59.000,9:59:59.000 Have you ever heard the sound of frogs 9:59:59.000,9:59:59.000 calling at night? 9:59:59.000,9:59:59.000 For hundreds of millions of years, 9:59:59.000,9:59:59.000 this croaking lullaby has filled the nighttime air. 9:59:59.000,9:59:59.000 But recent studies suggest 9:59:59.000,9:59:59.000 that these frogs are in danger 9:59:59.000,9:59:59.000 of playing their final note. 9:59:59.000,9:59:59.000 Over the past few decades, 9:59:59.000,9:59:59.000 amphibian populations have been rapidly disappearing worldwide. 9:59:59.000,9:59:59.000 Nearly one-third of the world's amphibian species 9:59:59.000,9:59:59.000 are endanger of extinction, 9:59:59.000,9:59:59.000 and over 100 species have already disappeared. 9:59:59.000,9:59:59.000 But don't worry, there's still hope. 9:59:59.000,9:59:59.000 Before we get into how to save the frogs, 9:59:59.000,9:59:59.000 let's start by taking a look 9:59:59.000,9:59:59.000 at why they're disappearing 9:59:59.000,9:59:59.000 and why it's important to keep them around. 9:59:59.000,9:59:59.000 Habitat destruction is the number one problem 9:59:59.000,9:59:59.000 for frog populations around the world. 9:59:59.000,9:59:59.000 There are seven billion humans on the planet, 9:59:59.000,9:59:59.000 and we compete with frogs for habitat. 9:59:59.000,9:59:59.000 We build cities, suburbs, and farms 9:59:59.000,9:59:59.000 on top of frog habitat 9:59:59.000,9:59:59.000 and chop forests 9:59:59.000,9:59:59.000 and drain the wetlands 9:59:59.000,9:59:59.000 that serve as home 9:59:59.000,9:59:59.000 for numerous amphibian populations. 9:59:59.000,9:59:59.000 Climate change alters precipitation levels, 9:59:59.000,9:59:59.000 drying up ponds, streams, and cloud forests. 9:59:59.000,9:59:59.000 As the Earth's human population continues to grow, 9:59:59.000,9:59:59.000 so will the threats amphibians face. 9:59:59.000,9:59:59.000 There are a variety of other factors 9:59:59.000,9:59:59.000 contributing to the frogs' decline. 9:59:59.000,9:59:59.000 Over-harvesting for the pet and food trade 9:59:59.000,9:59:59.000 results in millions of frogs 9:59:59.000,9:59:59.000 being taken out of the wild each year. 9:59:59.000,9:59:59.000 Invasive species, 9:59:59.000,9:59:59.000 such as non-native trout and crawfish, 9:59:59.000,9:59:59.000 eat native frogs. 9:59:59.000,9:59:59.000 Humans are facilitating the spread 9:59:59.000,9:59:59.000 of infectious diseases 9:59:59.000,9:59:59.000 by shipping over 100 million amphibians 9:59:59.000,9:59:59.000 around the world each year, 9:59:59.000,9:59:59.000 for use as food, pets, bait, 9:59:59.000,9:59:59.000 and in laboratories and zoos 9:59:59.000,9:59:59.000 with few regulations or quarantines. 9:59:59.000,9:59:59.000 One of these diseases, 9:59:59.000,9:59:59.000 chytridiomycosis, 9:59:59.000,9:59:59.000 has driven stream-dwelling amphibian populations 9:59:59.000,9:59:59.000 to extinction 9:59:59.000,9:59:59.000 in Africa, 9:59:59.000,9:59:59.000 Australia, 9:59:59.000,9:59:59.000 Europe, 9:59:59.000,9:59:59.000 and North, Central, and South America. 9:59:59.000,9:59:59.000 On top of all these problems, 9:59:59.000,9:59:59.000 we add hundreds of millions of kilograms of pesticides 9:59:59.000,9:59:59.000 to our ecosystems each year. 9:59:59.000,9:59:59.000 And these chemicals are easily absorbed 9:59:59.000,9:59:59.000 through amphibians' permeable skin, 9:59:59.000,9:59:59.000 causing amino suppression, 9:59:59.000,9:59:59.000 or a weakened immune system 9:59:59.000,9:59:59.000 and developmental deformities. 9:59:59.000,9:59:59.000 Okay, so why are these little green guys 9:59:59.000,9:59:59.000 worth keeping around? 9:59:59.000,9:59:59.000 Frogs are important for a multitude of reasons. 9:59:59.000,9:59:59.000 They're an integral part of the food web, 9:59:59.000,9:59:59.000 eating flies, ticks, mosquitoes, 9:59:59.000,9:59:59.000 and other disease vectors, 9:59:59.000,9:59:59.000 thus, protecting us against malaria, 9:59:59.000,9:59:59.000 dengue fever, 9:59:59.000,9:59:59.000 and other illnesses. 9:59:59.000,9:59:59.000 Tadpoles keep waterways clean 9:59:59.000,9:59:59.000 by feeding on algea, 9:59:59.000,9:59:59.000 reducing the demand 9:59:59.000,9:59:59.000 on our community's filtration systems 9:59:59.000,9:59:59.000 and keeping our cost of water low. 9:59:59.000,9:59:59.000 Frogs serve as a source of food 9:59:59.000,9:59:59.000 for birds, fish, snakes, dragonflies, and even monkies. 9:59:59.000,9:59:59.000 When frogs disappear, 9:59:59.000,9:59:59.000 the food web is disturbed, 9:59:59.000,9:59:59.000 and other animals can disappear as well. 9:59:59.000,9:59:59.000 Amphibians are also extremely important 9:59:59.000,9:59:59.000 in human medicine. 9:59:59.000,9:59:59.000 Over ten percent of the Nobel prizes 9:59:59.000,9:59:59.000 in physiology and medicine 9:59:59.000,9:59:59.000 have gone to researchers 9:59:59.000,9:59:59.000 whose work depended on amphibians.