Animal Facts Dolphin When a dolphin sleeps, half of its brain stays awake. Photo: Andy Rouse/Naturepl.com/Minden Pictures 144 facts found in category 'Mammals' Get Animal Facts by Category AmphibiansBirdsCollectionsCreepy CrawliesFishMammalsPrehistoricReptiles
Dolphin When a dolphin sleeps, half of its brain stays awake. Photo: Andy Rouse/Naturepl.com/Minden Pictures