Armed with spoonfuls of peanut butter, Richard Thorington has become well acquainted with the Eastern gray squirrels across the street from the White House. A curator of mammals at the National Museum of Natural History, Thorington has been working in Lafayette Park off and on for three decades, and if it seems odd that anyone could conduct original wildlife research in one of the nation’s most public places, that’s the advantage of studying squirrels. They’re, well, everywhere.

A good deal of what Thorington has learned about the commander in chief’s nuttiest neighbors appears in his new book, Squirrels: The Animal Answer Guide (Johns Hopkins University Press), a distillation of his more than 25 years of research on the squirrel family, which comprises 278 rodent species, including marmots, chipmunks and prairie dogs. The book, co-authored by Thorington’s former research assistant, Katie Ferrell, clears up such questions as whether squirrels fight (yes), see in color (yes), talk (yes—chuck chuck kwa means “cat on the prowl”) and swim (yes). Should people feed them? Sure, but not by hand, because of “how quick they are and how sharp their teeth are.”

Though widely recognized as a leading squirrelologist, Thorington, 69, started out in the 1960s studying primates in the forests of South America. Then, in 1976, he was diagnosed with Charcot-Marie-Tooth syndrome, a degenerative neurological disease, which would eventually make him quadriplegic and keep him from traveling and working in the tropics. He shifted his research to squirrels, taking advantage of the museum’s unparalleled collection of 30,000 squirrel specimens.

“The disability didn’t affect his eyes and observational powers,” says his wife, Caroline, a printmaker who also takes photographs of her husband’s squirrel subjects. “He’s always someone to say ‘what can I do?’ and not what he can’t do. He is always looking at natural history—he can’t help himself.”

In his backyard, in Bethesda, Maryland, Thorington has tested squirrels’ jumping ability by setting a hanging feeder near a tree stump and gradually moving the feeder farther and farther away. Finally, he found that only one squirrel could make the leap, a distance of eight feet. “After that experiment,” he says, “my neighbor complained that the squirrels were jumping to a bird feeder that they’d never been able to jump to before.”

To conduct field research, he cruises in his motorized wheelchair seven blocks from his overstuffed office at Natural History to Lafayette Park. Among other things, he observes the surprisingly complex way in which squirrels deploy their claws. “Ligaments in the toes pull the claws up” when they’re running in the grass, he says. “I’m studying the arrangement to see if it allows squirrels to rapidly retract their claws when climbing. When they’re bounding up a tree, they need to be able to both grasp the bark and let it go quickly.”

Not all of the animal’s abilities inspire admiration. These squirrels have been known to venture across Pennsylvania Avenue to wreak havoc on the presidential tulip bulbs. “A gray squirrel,” Thorington says, “cannot resist looking to see if you’ve buried something.”

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