eyewitness endangered animals

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eyewitness endangered animals

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[...]... available for the next level of animals in the chain As a result, there are always more animals lower down the food chain than at its top The most numerous animals are herbivores, which eat plants for hours on end each day Predators must work hard for every meal, and they are always rare, whether endangered or not E Extinct EW Extinct in the Wild CR Critically Endangered EN Endangered VC Vulnerable NT... species on the Red List is given a category About 700 animals are listed as Extinct—there is nothing we can do for them Extinct in the Wild means a species survives only in zoos Critically Endangered species cling on in the wild, in tiny numbers Endangered animals have larger populations, but are still at risk Vulnerable animals will soon become Endangered if not protected Near Threatened species are... fittest.” The fittest animals are those best suited to their particular way of life A fit giraffe has a longer neck and can get more food than giraffes with shorter necks The fittest animals survive and have offspring, while the weaker ones die out Darwin called this natural selection— nature determines which animals thrive Habitats change, and new animals become a success Slowly, the animals evolve into... poachers killed the giant animals for their ivory tusks In 1989, selling ivory was banned, but the danger remained In 1996, the elephants became Endangered However conservation programs eventually began to work, and by 2008 African elephants were recategorized as Near Threatened 16 BEHIND THE NUMBERS Endangered animals are not just those with small populations Green turtles are listed as Endangered even though... larger animals eat these pest insects, the poison builds up inside them The insecticide DDT endangered hunting birds in this way (see page 42) FROM SOIL TO DUST Most agricultural animals are grazing mammals that used to wander far and wide to find food in the wild However, farmers often try to keep more animals than the local vegetation can support Plant roots bind the soil, and when grazing animals. .. fields turn into desert PRICE OF LUXURY A MEATY COST Pastrami sandwich Raising animals for meat requires a lot more farmland than growing plant foods Two-thirds of all farmland is used for grazing animals Livestock animals grow faster if they are fed rich plant food In the US, 70 percent of grain crops are fed to animals Raising animals for meat also uses 100 times more water than cultivating crops As the... frogs FARM FRIENDLY Some animals have benefited from farming The cattle egret follows herds of grazing animals and snaps up insects and worms disturbed by the large animals hooves Cattle egrets once lived mainly in Africa, but in less than a century, they spread across Europe and traveled with imported cattle to the Americas and Australia SQUEEZED OUT Some animals become endangered when the effects... caused by outside factors can have an impact on the animals living there There are few habitats left on Earth that have escaped the effects of human activity, and damage to habitats is perhaps the main cause of animals becoming endangered While large animals such as whales, rhinos, and tigers are at risk from direct attacks by people, many more smaller animals, such as insects, fish, and songbirds, are... bacteria, which harness the energy in sunlight to make their food These are producers, and they are consumed by small animals, or primary consumers Larger animals then prey on these primary consumers, with some species eating both plants and animals The web continues up to the top predators These animals have no enemies, but they rely on all the members of the food web below them for their survival UPS AND... will not be a surprise if many of these unchecked animals are also found to be endangered Sadly, one of the first things that has to be done once a new species of animal has been studied is to figure out how to stop it from becoming extinct EXPERTS AT WORK The IUCN relies on hundreds of experts to provide information on different groups of endangered animals Project Seahorse is an international conservation . saint of animals. There are many stories about how this 12th-century monk cared for animals because he believed it was the right thing to do. Today’s conservationists protect endangered animals. small animals, or primary consumers. Larger animals then prey on these primary consumers, with some species eating both plants and animals. The web continues up to the top predators. These animals. species cling on in the wild, in tiny numbers. Endangered animals have larger populations, but are still at risk. Vulnerable animals will soon become Endangered if not protected. Near Threatened

Ngày đăng: 10/01/2015, 21:22

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Mục lục

  • 5 Contents

  • 6 Wildlife under threat

  • 8 What is a species?

  • 10 Adapting and survival

  • 12 The variety of life

  • 14 Links in the chain

  • 16 Measuring risk

  • 18 Watching animals in action

  • 20 Going, going, gone

  • 22 Lost and found

  • 24 Boom and bust

  • 26 The rise of humans

  • 28 The impact of farming

  • 30 A world without bees?

  • 32 Crowded out

  • 34 Damaged landscapes

  • 36 Climate change

  • 38 Global amphibian decline

  • 40 Rivers in crisis

  • 42 Polluted world

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