Part 8/11:
He entertains outlandish theories, such as beings living in Antarctica or hidden under the oceans—places humans seldom travel or explore deeply—possibly thriving in hidden ecosystems. He relays a curious report of a pilot discovering a lush, tropical environment inside a cave, inhabited by ancient beings who might have been there for thousands of years, raising questions about whether humans are truly the "earthlings" or if perhaps other species arrived long before us.