November 4, 2020
A recent study of fossils excavated from Egg Mountain Montana pushes back the origin of social behavior among mammals to the Cretaceous Period. The fossils date to the Late Campanian (ca. 75.5 mya) and represent the most complete and well-preserved mammal specimens known from North America for this period. Contextual and functional analyses suggest these rodent-like fossils burrowed and nested in groups, forcing a reconsideration of when such social behavior began in mammals.
Check out Dr. Sargis’s research in Yale News and his co-authored journal article in Nature Ecology & Evolution.