Meet the animals who live in nature's winter wonderlands,from the polar bear mother who gives her cubs the best possible start in life to the owl that finds food hidden beneath a blanket of snow, plus the plucky penguins that huddle together to keep warm.
As the days shorten and the temperature drops, the inhabitants of Nunavik, Quebec prepare to face the approaching arctic winter. Watch as muskoxen fatten up, ptarmigans hunt for berries, and Inuit make use of the last warm days of the year.
When you're a baby zebra, muskox, or pronghorn, there is no shortage of predators eyeing you as their next meal. From learning defensive herding to early sprinting skills, these vulnerable newborns hit the ground running with keen survival instincts.
The Cretaceous was the golden age on ancient Earth. Magnificent and terrifying dinosaurs like Triceratops and Tyrannosaurus ruled the land. But they were all wiped out in an instant by one of the most powerful impacts our Earth has ever endured -- a collision with an asteroid!
Dr Helen Czerski examines the hottest natural phenomena on the planet - lightning. Bolts of lightning five times hotter than the surface of the sun strike our planet over 3 million times every day - and yet we still know little about this deadly force of nature. Now, specialist photography is revealing how lightning travels through the air, high-speed cameras are unlocking the secrets of upward lightning that's triggered by our urban landscapes, and scientific expeditions are capturing rare images of intense electrical discharges over 80 kilometres wide.