"It's quite an experience to walk through the woods and suddenly see tree trunks that turn out to be legs," said biologist Mary Lang Edwards after meeting a giraffe on a Thomson safari. "They're five times longer than our legs."

Indeed, a male giraffe may grow to 18 feet, a female to 15 feet. And the appearance that their legs are longer in front than in back is an optical illusion. A giraffe galloping across the plains or spreading its front feet wide to drink from a watering hole seems to have extra-long front legs because of its steeply sloping back, which rises to high shoulders that support the neck that make it the tallest animal on earth.

Within the single species of giraffe (giraffa camelopardalis) occur eight subspecies or races, each distinguished by its markings. The type most commonly found in Tanzania is the Masai giraffe, its ochre-colored coat splashed with irregular, dark brown patches like puzzle pieces. Even within the pattern types, the markings of an individual giraffe, like the fingerprints of a human, are unique.

Inside a giraffe's head, with its kind brown eyes and knobby horns, lurk some secrets. The giraffe's long tongue, for instance, extends 18 inches and is prehensile, so the giraffe can stick it out and wrap it around a bunch of leaves, or select a few tender shoots from a thorny branch, and pull the greenery deftly toward its ruminant stomach. A giraffe needs a strong tongue to get all the food it needs -- up to 75 pounds a day!

A male giraffe also needs a hard head to win the competitive game of courtship in the veldt. From the age of four, when his horns first attach to his skull, a bull giraffe grows layer after layer of new bone which accumulates around his skull, especially over his eyes and on his nose. Gradually, his head becomes a massive club that he uses to strike competitors. The ritual of fighting for a female begins with a stiff-legged dance. After rubbing necks and leaning on each other to gauge their relative strength, two bulls swing their heads up and over the shoulder, often missing but sometimes hitting each other's flanks and necks. Between blows, there are long pauses when the animals stand motionless.

The winner -- the one that doesn't run away -- follows his chosen cow and rests his head on her back, nibbles at her tail, curls his lip while she urinates, and otherwise dotes on her until they mate. If she becomes pregnant, she will deliver a single six-foot baby in about 14 1/2 months. Young giraffes often stay together in nurseries so their mothers can travel to water, which they need every 2-3 days. Males tend to stay with their mothers until age three, when they form bachelor herds. Females usually remain in the area of their birth, mothers and daughters providing a loose form of social stability.

Although giraffes are gregarious in that they live with their own kind, they form groups that seem too informal to be called herds. They come and go almost at random. Individuals may spend the day 20 yards or more apart, with no leader and little coordinated movement.

You may have heard that giraffes make no sounds and have no enemies. Neither is strictly true, according to African wildlife specialist Richard Estes. He describes giraffes as "silent but not mute," and notes that they snort to express alarm, bleat to find their mothers, bellow to find their babies, and serenade their mates with a raucous coughing sound. In addition, Estes says, "moaning, snoring, hissing, and flutelike sounds have also been reported."

As for enemies, adult giraffes can defend themselves against almost any predator. They fall prey to lions occasionally, but their superior vision, size, speed, and sharp hooves protect them well. Young giraffes are vulnerable to both lions and hyenas. Their mothers often kill lions, however, with well-placed kicks from powerful legs and sharp hooves. Females never use their horns to fight, according to Estes, and males use them only in competition with peers.

Giraffes have only two gaits: ambling and galloping. When they walk, the left legs move together, then the right. When they gallop, the forefeet and hindfeet move together in pairs, like a jackrabbit, the hind legs landing outside and ahead of the forefeet at over 30 miles per hour. By avoiding cross motion, giraffes manage not to trip themselves.

Giraffes spend about half of each 24 hours feeding, especially during the first and last three hours of the day, according to Estes. The rest of the time, they sleep or lie around and cultivate their reputation for being some of the most peaceful animals in Africa.