The Joanine Library at the University of Coimbra in Portugal houses almost 60,000 volumes—and a colony of bats that keep harmful insects at bay:
“In the daytime—as scholars lean over historic works and visitors admire the architecture—the bats roost quietly behind the two-story bookshelves. At night, they swoop around the darkened building, eating the beetles and moths that would otherwise do a number on all that old paper and binding glue.” - Atlas…