Unearth the nine massive prehistoric animals that lived before ... there are no present-day sea scorpions. The Dimetrodon lived during the early Permian Period, and while it looks reptilian ...

Less than 5 percent of the animal species in the seas survived ... For years scientists have known that the deep ocean lacked oxygen in the late Permian. But most life is concentrated in shallow ...

With less oxygen, many ocean animals would die. Tomorrow in Wonderopolis, become the star of your own bedtime story. All you need is a dash of imagination and a pair of pajamas. Ready to DIG deeper ...