The human eye is an amazing mechanism, able to detect anywhere from a few photons to a few quadrillion, or switch focus from the screen in front of you to the distant horizon in a third of a second. How did these complex structures evolve? Joshua Harvey details the 500 million year story of the human eye.
Even after thousands of years of ice crushing the northern hemisphere and temperatures of 20 degrees lower than those of today, many of the great giants of the ice age still walked the earth. It was only when the world had warmed up again that mammoths, woolly rhinos, sabre-toothed cats, giant ground sloths and glyptodonts finally became extinct. Professor Alice Roberts sets off on her last voyage back to the Ice Age to discover why.
The story of animals surviving one of the harshest seasonal changes on the planet continues. It is summer and the Yellowstone beavers have a new challenge. Will the young survive as the river dries up and the colony is forced to move home? As food becomes scarce, wolves have a surprising strategy to keep their pups fed and grizzly bears are unexpected visitors on a cowboy ranch. By midsummer, the hot dry conditions create a new danger - deadly wildfires burn out of control and threaten to engulf a family of great grey owls. 2016 was the hottest year on earth since records began, and across Yellowstone scientists reveal the effects of rising temperatures on the animals that live here.