It has been proposed that North American polar dinosaurs may have migrated to warmer regions as winter approached, which would allow them to inhabit Alaska during the summers even if they were cold-blooded.
Predloženo je da su sjevernoamerički polarni dinosauri možda migrirali do toplijih regija kako se zima približavala, a da su na Aljasci živjeli tijekom ljeta čak iako su bili hladnokrvni.