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to be just scavengers (animals that eat the meat left behind by predators). But now we know that they're very good at finding their own food, too.

Hunting together in large packs, hyenas have a very effective way of catching their favorite food. One hyena scares a herd of wildebeest, looks for the weakest member of the herd, and then begins a chase. The other hyenas join in the attack, and a wildebeest feast is soon ready.

If you've ever heard the expression "laughing hyena" and wondered where it came from, it was inspired by the strange, laughter-like sound hyenas make when they're being attacked or chased.

EATING HABITS

True hyenas have thickset muzzles with large ears and eyes, powerful jaws and big cheek teeth to deal with a carnivorous diet. They walk on four-toed feet with five asymmetrical pads and nonretractile claws. The tail is long and bushy (less so in the spotted hyena). Spotted hyenas will eat almost anything, but in the wild much of their food comes from mammals heavier than 44 lb. which they mostly kill for themselves. The frequency of hunting depends on the availability of carrion; spotted hyenas will loot the kills of other carnivores, including lions. Group feeding is often noisy, but rarely involves serious fighting. Instead, each hyena gorges extremely rapidly on up to 33 lb. of flesh. Pieces of a carcass may be carried away to be consumed at leisure or, occasionally, stored underwater.

It seems that the success of spotted hyenas is ensured through individual and cooperative hunting and sharing of food between adults. Cooperation also extends to communal marking and defense of the territory, in which both sexes play a similar role, whether or not they are related. Competition within the clan can, however, be intense. The system of communication shows adaptations, which reduce aggression and coordinate group activities. Such competition probably provided the selection pressure whereby females evolved their large size and dominant position, which in turn relates also to levels of testosterone in the blood that are indistinguishable from those of the male. Thus female spotted hyenas are able to feed a small number of offspring alone and protect them from the more serious consequences of interference by other hyenas, particularly unrelated males.

WHY THEY LAUGH

Hyenas are often called "solitary," a label which obscures the fact that their social systems are among the most complex known for mammals. Spotted hyenas employ elaborate meeting ceremonies and efficient long-range communication by scent and sound. Even when moving alone, spotted hyenas maintain some direct contact with their fellows. They respond to sounds, which are only audible to humans with the aid of an amplifier and headphones.

Calls audible to the unaided human ear include whoops, fast whoops, yells and a kind of demented cackle that gives this species its alternative name of laughing hyena. Whoop calls, in particular, are well-suited to long- range communication as they carry over several kilometers; each call is repeated a number of times, which helps the listener to locate the caller, and each hyena has a distinctive voice. Infant hyenas will answer the pre-recorded whoops of their mothers, but not those of other clan hyenas.

LIONS AFRICAN LION: FAMILY CATS

Lions are among the most admired animals on earth. Their strength and beauty, combined
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with their bold nature, have fascinated people for ages. In fact, the lion has often been called the "king of the beasts." And when you see a big male lion, with its magnificent main and proud walk, it's easy to understand why. Lions really do look like kings.

But lions don't always lead the easy lives of kings. They often need to work hard to survive. Lions are meat eaters, or carnivores, so they must hunt other animals for food. And sometimes prey is hard to find. When food is scarce, a lion may go for days without eating.

Lions are members of the big cat family, which includes tigers, leopards, and jaguars. The main difference between the big cats and all other cats is that generally big cats can roar but cannot purr. Other cats can purr but cannot roar.

The lion is one of the biggest cats in the world. Only the Siberian tiger is larger. A male lion may be 9 to 10 feet long (3 meters) and can weigh 500 pounds (227 kilograms) or more. Female lions are smaller. The average female is 7 to 8 feet long (2 l/2 meters) and weighs 270 to 350 pounds (140 kilograms).

Lions are different from most other cats in that they live in groups called prides. They hunt together, guard their territory together, and raise their young together. Lions that live in groups can catch more food than a single lion can. And they can protect themselves better. Also, lions that are born into groups have a large family to care for them.

There are two different kinds, or subspecies, of lions: the African and the Asiatic. Most of the lions in the world today are African lions. These animals live on the grassy plains of Africa. The few Asiatic lions that remain live on a small wildlife preserve in India. There were once many other kinds of lions in the world but all of these are now extinct.

Lions sometimes climb high up into trees to rest on their branches and escape the biting insects below.

The body of a lion is made for catching prey. Most of the time, lions try to get very close to their prey before they attack it. Then they make a big leap and grab the prey. To help them get close without being seen, lions have golden-brown coats that blend in with the land around them. And to help them leap, they have strong muscles in their legs. A lion can leap 35 feet (10.5 meters) through the air in a single jump.

Lions do most of their hunting at night, so they have wonderful hearing and eyesight to help them find prey in the dark. Their hearing is so sharp, they can hear prey that is more than a mile away. Lions can turn their ears from side to side to catch sounds coming from almost any direction. When a lion is moving through tall grass, it may not always be able to see its prey -- but it can always hear it. The eyes of lions are the biggest of any meat-eating animal. Like the eyes of other cats, they are specially made for seeing at night.

Lions often work together when they hunt. By doing this, they increase their chances of getting food. A lion that hunts alone may have a hard time catching prey.

Most of the hunting is done by a team of females. They divide the job among them, with each female doing part of the work to catch the prey. Some of the females scare prey animals and make them run -- while other females lie in ambush to grab the fleeing animals.

The extra strength of a male is sometimes needed to bring down larger animals, like wildebeest

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