Dome-headed, small-brained island mammal from the Late Cretaceous of Romania

Significance Island-living animals often differ from close relatives and mainland contemporaries in unusual ways, as best demonstrated by modern and Cenozoic mammals that are dwarfed or evolved aberrant anatomical features. However, it is unclear whether mammals from the Age of Dinosaurs followed this same pattern. We describe the fossil skeleton of a previously undiscovered peculiar Cretaceous island-dwelling mammal from Romania, which has a...