Ever wonder how the heart symbol came to stand for the actual heart? And why do we speak of the heart as the seat of love, when love really happens in our brains? Is it true that animals only get a billion heartbeats? This week, we give you enough cool cardiac science to make your heart skip a beat.
Why do we sleep? We spend a third of our lives in slumber, but science has yet to determine exactly why we have do it. Here’s a look at how sleep works, why we’re not getting enough sleep, what happens if you DON’T sleep, and an idea about where sleep came from in the first place.
2015 • Health
Svalbard in the Arctic spends many months of the year in complete darkness, an unrelenting frozen winter with temperatures down to -40 Celsius. But when the sun finally reappears, the landscape magically transforms from an ice world into a rich tundra, full of exotic plants, birds, arctic foxes, polar bears, walrus and reindeer. This film captures the changes in all their glory and reveals how this transformation is only possible thanks to some bizarre micro-organisms that feed on ice and the stunning abilities of migrating birds.
In the northeast corner of Botswana, the rainy season is months away. The sausage tree offers a beguiling oasis for wildlife--from birds and insects, to much larger mammals like elephants--all reeling from the dry conditions. Then, as the rains descend, brilliant red flowers bloom and entice parrots, squirrels, and sunbirds to help with pollination. Summer allows the sausage tree to live up to its name, delivering massive, sausage-shaped fruit, a nutritious feast and a cornerstone of life in this exotic ecosystem.
The annual migration of wildebeest through the plains of the Serengeti reaches its unforgiving apex at the banks of the crocodile-infested Mara River. Undeterred, the herd leaps in despite the deadly predators within. Join wildlife expert Jean du Plessis as he charts this epic and often-deadly journey.
The Mesoamerican Reef is the second longest on the planet--a threatened world of coastal wetlands, mangrove forests, and seagrass beds. That it exists at all is testament to decades of tireless activism, sustainable tourism, responsible fishing, and strict policing. Join us as we tour its many delights.