Each ecological radiation generated new varieties of mammaliaforms from more primitive, insect-eating, rodent-like ancestors. Many of the diverse forms that arose during the Jurassic and Cretaceous resemble species alive today, such as badgers, flying squirrels, and even anteaters. But these dinosaur-era mammaliaforms are not the direct ancestors of their modern counterparts.

“These same ecological adaptations—for gliding, climbing, eating diverse diets—have evolved repeatedly in the history of mammals and their close relatives,” says Grossnickle.

Source: Fossils bust myth about mammals in dinosaur age – Futurity