The bat, say scientists, is one of nature’s most dazzling and precious creations. According to the fossil record, bats were soaring in the sky at least 55 million years ago. These ancient fliers, says evolutionary biologist Nancy Simmons of New York’s American Museum of Natural History, were “virtually indistinguishable from today echolocating bats”. Though to look at them most resemble rodents, bats’ closest cousins are primates. Modern bats are amazingly diverse, about 1,000 species account for nearly a fourth of all mammal species. The only known group of flying mammals, they range in size from Thailand’s tiny bumblebee bat, weighing almost nothing, to Indonesia’s giant flying fox, with wingspans of nearly 5 ft. Many bats feed on insects, while others prefer fruit, nectar, or pollen. A few feast on fish, rodents, and blood. Contrary to legend, however, vampire bats, which dwell in Latin America, suck the blood of grazing cattle and horses, not sleeping humans.
Essentially docile, bats play a vital role in maintaining ecological balance. For one thing, they protect crops from marauding insects. The 20 million Mexican free-tailed bats that roots in Bracken Cave near San Antonio, Texas, from spring to fall consume 250 tons of insects every night as they swarm to altitudes of more than 10.000ft. A single little brown bat can also lap up 600 mosquitoes an hour.
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