Colophon

The animal on the cover of Hadoop: The Definitive Guide is an African elephant. They are the largest land animals on earth (slightly larger than their cousin, the Asian elephant) and can be identified by their ears, which have been said to look somewhat like the continent of Asia. Males stand 12 feet tall at the shoulder and weigh 12,000 pounds, but they can get as big as 15,000 pounds, whereas females stand 10 feet tall and weigh 8,000–11,000 pounds.

They have four molars; each weighs about 11 pounds and measures about 12 inches long. As the front pair wears down and drops out in pieces, the back pair shifts forward, and two new molars emerge in the back of the mouth. They replace their teeth six times throughout their lives, and between 40–60 years of age, they will lose all of their teeth and likely die of starvation (a common cause of death). Their tusks are teeth—actually it is the second set of incisors that becomes the tusks, which they use for digging for roots and stripping the bark off trees for food, fighting each other during mating season, and defending themselves against predators. Their tusks weigh between 50–100 pounds and are between 5–8 feet long.

African elephants live throughout sub-Saharan Africa. Most of the continent’s elephants live on savannas and in dry woodlands. In some regions, they can be found in desert areas; in others, they are found in mountains.

Elephants are fond of water. They shower by sucking water into their trunks and spraying it all ...

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