Colophon

The animal on the cover of sendmail is flying fox, a species of fruit bat found chiefly on the islands of the Malay-Indonesia archipelago. Of about 4,000 species of mammals, nearly one-quarter are bats; and of these, 160 are fruit bats. Sixty of the larger fruit bats make up the flying foxes, the largest having a wingspan of five feet. While smaller insect-eating bats navigate by echolocation, fruit bats depend on a keen sense of sight and smell to perceive their environment. They roost in trees by day, sometimes in extremely large numbers called “camps.” They hang from branches by one or both feet, wrap themselves in their wings, and sleep the day away. On hot days, these bats keep cool by fanning themselves with their wings.

Greatly elongated fingers form the main support for the web of skin that has allowed these mammals, alone, to master true flight. At sunset they awaken from their slumber and begin their nocturnal ramblings. A flying fox must flap its wings until it becomes horizontal to the ground before it can let go and fly away. Once airborne, they use their sensitive sense of smell to detect where flowers are blooming or fruits have ripened. Unlike most animals, fruit bats cannot generate vitamin C (a limitation shared by humans and guinea pigs); thus, it is supplied by fruit in the diet. Flying foxes can range up to 40 miles for food. Once a target is located, they are faced with a difficult landing. Sometimes they will simply crash into foliage and grab at what ...

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