Centuries of human history have been frozen in time inside the towering nests of bearded vultures, Europe’s most endangered raptors, and have revealed a surprising archive of ancient artefacts carried aloft by the birds themselves. A Spanish research team who were excavating 12 ancient eyries in southern Spain’s rugged cliffs uncovered 2,483 preserved remains in a study published recently in the Ecology journal. Among them: 2,117 animal bones, 86 hooves, 72 leather scraps, 43 eggshell fragments—and 226 human-made objects, some dating back over 650 years via carbon-14 analysis. “These nests have acted as natural museums,” the authors wrote, who credited...