#Dinosaurs needed to be cold enough that being #warmblooded mattered
Researchers now think dinosaurs that already had some cold tolerance evolved #endothermy, or warm-bloodedness, to adapt when they migrated to regions with cooler temperatures, many dinosaurs from these groups are thought to have been feathered. Feathers can be used to both trap and release heat, allowing dinosaurs to regulate their body temperature in more diverse climates. Birds use feathers same way.
https://arstechnica.com/science/2024/05/when-warm-blooded-dinosaurs-first-roamed-the-earth/