Refoxos, Spain—When the researcher arrives, Herminia is already waiting for him, calmly seated on a chair in her courtyard, a leafy shelter providing protection from the unseasonably hot Sun. She wears a simple dark blue dress and her hands rest on her lap. She smiles at the visitors but doesn’t stand up—she fell a few days ago and has a sore leg. Nothing too serious, but when you are 101 years old you need to be cautious.

Herminia has spent all of her long life here in Refoxos, a small parish of about 100 people in southern Galicia, in Spain. In many regions of the world, her old age would make her unusual—but here she is not an outlier. Herminia’s father died at age 96 and her husband, who passed away last year, made it to 103. Many of her neighbors are well into their 80s and 90s. It’s this remarkable longevity that has brought José María Failde and his colleagues at the University of Vigo to the town.