On a Sunday morning in a decaying and dangerous inner-city barrio in Lima, Peru, an unmarked white van carrying nearly a dozen bodies rumbles to a stop on the grounds of the National Institute of Neurological Sciences. Seated in a small waiting area to the rear of the building, a throng of well-dressed researchers and government officials watches intently. As the driver clambers out, an assistant hustles off in search of a hospital gurney. Within minutes, two men wheel the first body into the institute's imaging unit.
Onlooker Caleb Finch, a biologist at the University of Southern California, has been waiting for this moment for months. Tall, gaunt and graying, with a Father Time–style beard, the 74-year-old scientist has devoted his career to the study of human aging. Our kind is remarkably long-lived compared with other primates. Our nearest surviving relatives, the chimpanzees, have a life expectancy at birth of about 13 years. In contrast, babies born in the U.S. in 2009 possessed a life expectancy at birth of 78.5 years. Finch has come to Lima to find out why—by peering into the distant past. The cadavers in the van belong to men, women and children who perished along this stretch of coastal desert as much as 1,800 years ago, long before the Spanish conquest. Cocooned in dusty textiles and interred in arid desert tombs, their naturally mummified bodies preserve critical new clues to the mystery of human longevity. As envoys from an era long before modern health care, they will offer case studies of aging in the past. Finch walks over to the van, grinning as he surveys the cargo. “That's a pack of mummies,” he says.