Fossilized teeth from juvenile Maiasaura, a duck-billed dinosaur from the Late Cretaceous, reveal that babies ate a diet richer in soft, nutrient-dense plants than their parents. Researchers analyzed dental wear patterns and found significantly more crushing surfaces in juveniles, indicating consumption of berries, buds, and other low-fiber foods, while adults primarily processed tough, fibrous vegetation. This dietary difference suggests that adult Maiasaura actively provisioned their young—a behavior previously thought to be rare or absent in non-avian dinosaurs. The finding parallels modern nesting birds and supports the idea of sophisticated parental care in dinosaurs long before birds evolved. The study was led by John Hunter of Ohio State University and Christine Janis of the University of Bristol, using microwear analysis calibrated against living herbivorous mammals.