This instalment is the first of several to concentrate on mammals. The platypus and the echidna are the only mammals that lay eggs (in much the same manner of reptiles), and it is from such animals that others in the group evolved. Since mammals have warm blood and most have dense fur, they can hunt at night when temperatures drop. It is for this reason that they became more successful than their reptile ancestors, who needed to heat themselves externally. Much of the programme is devoted to marsupials (whose young are partially formed at birth) of which fossils have been found in the Americas dating back 60 million years.
In which John Green and Hank Green teach you about how human primates moved out of Africa and turned Earth into a real-life Planet of the Apes. And the apes are people! John and Hank teach you about how humans evolved, and the sort of tricks they picked up along the way like complex tool use, big brains, and fighting. Learn more: http://www.bighistoryproject.com
Forty miles north of Honduras, near the Bay Island of Roatan, is a spectacular and pristinely preserved coral atoll: the Mesoamerican Reef. Explore the abundant and diverse marine life, lush vegetation, and magnificent caves of this rare underwater wonder.
Despite the scorching heat, a cold upwelling of nutrients in the Gulf of Oman creates favorable conditions for a host of marine migrants. The behemoth whale shark, hawksbill turtle, and millions of tiny, exotic fish settle in to feast. Take a plunge into the algae-cloaked coral reefs of this underwater tapestry.