What Can One Disease Do to a Landscape?
After the vicuñas in Argentina’s San Guillermo National Park caught mange from domesticated llamas, the world around them changed.
The past two years have shown just how badly a disease that originated in wildlife can upend the human world. But epidemics can also move in the opposite direction, with equally dramatic results. Argentina’s San Guillermo National Park, for example, was once dominated by the puma—a top predator that, by controlling grazing animals, determined the patterns of plants across the landscape. But the puma was ousted from its role as the park’s chief terra-former by a disease, which radically reshaped the entire ecosystem in a few short years.
Julia Monk of Yale and Justine Smith of UC Davis were . For years, they had been studying the park’s wildlife, including its vicuñas—smaller relatives
