Pleistocene Pocket Gophers From San Josecito Cave, Nuevo Leon, Mexico

Nestled high in the pine‑oak forests of the Sierra Madre Occidental, San Josecito Cave has yielded a remarkable snapshot of life at the edge of the last ice age. Within its limestone chambers archaeologists uncovered a rich assemblage of vertebrate bones, from towering megafauna such as saber‑toothed cats and ancient horses to the tiny creatures that scurry beneath the soil. The collection offers a rare window into the ecosystems of northeastern México during the late Pleistocene, helping scientists trace how modern animal distributions have shifted over millennia.

Among the most intriguing finds are the pocket gophers, whose fossilized skulls and teeth reveal three distinct lineages, including a previously unknown form. Careful comparison with living relatives shows subtle differences in size and morphology, suggesting that these subterranean rodents once inhabited elevations where they are absent today. By piecing together these details, the study illuminates the dynamic evolutionary history of Mexico’s small mammals and the broader patterns of change that shaped the region’s ancient landscapes.