IN PRAISE OF SNAKES

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Ever since the wily serpent urged Eve to take that fateful bite out of the apple, snakes have been on just about everybody's enemies list. In the Old West, calling someone a "rattlesnake" or "snake in the grass" could get you shot. Even newborn monkeys recoil instantly when shown the image of a snake. Is there anyone who has something good to say about the creatures?

As it happens, there is. Harry Greene, 52, a soft-spoken, Southern-accented biology professor at the University of California, Berkeley, not only believes snakes have been badly maligned but has also made it his life's work to wage war on ophidiophobia (fear of snakes). It hasn't been easy, he admits. Even the saintly Albert Schweitzer, who went out of his way to avoid stepping on bugs, didn't hesitate to shoot the beings whose distinguishing characteristics are a slithering gait, a forked tongue and hypodermic-needle fangs that can (if they belong to Australia's cobra-like inland taipan) deliver enough venom in a single bite to kill 200,000 mice.

Greene, who describes himself as "stuck on snakes," believes they deserve a better rep. A collector since he was a seven-year-old in rural Texas, he sees them as far more interesting biologically and aesthetically than even fellow scientists once thought, and his research on snake behavior has helped show why. "Snakes are natural puzzles, suggestive of things that haunt and inspire us," he writes in his new book, Snakes: The Evolution of Mystery in Nature (University of California; $45). At once a paean to serpents and an encyclopedic review of what's known and not known about them, the book argues that instead of hunting snakes down to near extinction, as we've done with the timber rattler--once glorified on the American Revolution's "Don't Tread on Me" flag--we ought to consider them "worthy of respect" and deserving of "a place in nature."

But how? For one thing, Greene says, we should suspend our natural preference for animals with fur, feathers and facial expressions. Then, he says, we would be able to start appreciating snakes for their "special beauty and mystique"--and for such unique characteristics as their extraordinary sense of smell, their amazing versatility, their stunning coloration and a repertoire of deadly toxins that could serve as a model for future drugs.

Guiding a dubious visitor through the double-bolted doors of the venomous-snake room at Berkeley's Museum of Vertebrate Zoology, where he is curator of herpetology, Greene emphasizes his point by plucking a yard-long Western rattlesnake out of its cage. "Touch his skin or feel his rattle," he says. "They're really works of art."

To Greene, the greatest achievement of the snake is how well it has adapted to its varied environments. Like sharks, which have a similar image problem, snakes occupy almost every available ecological niche except the polar regions, from rain forests to deserts to the sea. Probably descended from nearly limbless lizards that lived during the age of dinosaurs 90 million years ago, snakes are divided into some 2,700 species, ranging in size from pencil-long African thread snakes to gigantic 20-ft. pythons and anacondas that are big enough to swallow a human. To fit into a cylindrical body, their viscera are ingeniously modified--with organs either shrunken or stacked on top of one another.

Males have paired sex organs--each called a hemipenis, or half penis--hidden in the base of the tail. Some species, such as common king snakes, deploy these alternatively in successive matings--perhaps, says Greene, to allow more frequent copulation. When Borneo's yellow-lipped sea- kraits breed, as many as half a dozen males may pile on a lone female. Copulation is usually brief but can last more than a day for Western diamondbacks (probably to reduce the female's exposure to rival males). Female snakes too deploy cunning reproductive strategies. North American pit vipers, for example, store sperm for months, until some instinct tells the cold-blooded creatures that the temperature is right for fertilization. Like birds (close kin), most species are egg layers, though some give birth to fully formed young.

The hatchlings of some species exhibit survival strategies that might seem beyond their tiny reptilian brains. Young Eastern hog-nosed snakes, for example, feign death if they sense a threat. Are they consciously aware of danger? Or, as Greene puts it, "Does a mere serpent have reflections and intentions?" To learn more about snake behavior, Greene and his colleagues are going to plant tiny radio beepers inside newborn rattlesnakes. Says he: "Radio telemetry allows us to wonder more accurately what it's like to be a snake."

Most astonishing to Greene are snakes' keen senses--of smell, temperature and touch--which make up for their lack of external ears and limited vision (except for night snakes, which have catlike eyes). That flickering forked tongue, for example, loathsome as it may seem, actually gives the snake the chemical equivalent of stereoscopic vision; by responding to the relative number of odors on either side of the tongue, the snake can pinpoint potential prey, mates or enemies. Pit vipers, for their part, are equipped with keen infrared sensors near their nostrils, so even if blinded, they can strike a mouse several feet away simply by detecting its body heat.

Greene, who wrote his book in response to a challenge from the late writer Norman Maclean (A River Runs Through It)--"Look, just tell me why you work with those damned old rattlesnakes," Maclean said--makes no excuses for them. Snakes kill more than 20,000 humans a year, he admits, mostly farmers in the tropics who are accidentally bitten by vipers, although boots and antivenom have reduced the toll in recent years. In the U.S., where 1,000 to 2,000 snakebites occur annually, mostly by rattlesnakes and copperheads, fewer than 10 result in death. The majority of victims, says Greene, who has been nailed only once ("not seriously" by a copperhead as a teen), are "macho types"--young men who handle venomous snakes carelessly. "Snakes are more afraid of us than we are of them," he insists. "They'll only bite if they perceive a threat." Of course, you'd expect to hear that from an ophidiophilic scientist whose E-mail handle is crotalus, the genus name for rattlers.