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
Steve Backshall lifts the lid on an incredible world of intricate relationships and unexpected hardship in the Amazon rainforest, explores the way that the jungle's inhabitants interact, and reveals a hidden secret that might just be what keeps the whole place alive.
For the animals in the polar regions, autumn means dramatic battles and epic journeys. Time is running out - the Arctic Ocean is freezing over and the sea ice is advancing at 2.5 miles per day around Antarctica. Polar bears gather in large numbers on the Arctic coast as they wait for the return of the ice. Soon, tempers fray and violent sparring contests break out. Meanwhile 2,000 beluga whales head for one special estuary, a gigantic 'whale spa' where they will thrash their snow-white bodies against the gravel and exfoliate. Inland, the tundra undergoes a dramatic transformation from green to fiery red. Here, musk ox males slam head-first into each other with the force of a 30mph car crash as they struggle to defend their harems. Frisky young caribou males play a game of 'grandma's footsteps' as they try to steal the boss's female. Down in Antarctica, Adelie penguin chicks huddle together in creches. When a parent returns from fishing, it leads its twins on a comical steeplechase - sadly there's only enough for one, so the winner gets the meal. Two months later and the chicks are fully feathered apart from downy Mohican hairdos - they're ready to take their first swim - reluctantly though, as it seems penguins are not born with a love of water! And with good reason - a leopard seal explodes from the sea and pulls one from an ice floe, a hunting manoeuvre that has never been filmed before. As winter approaches and everyone has left, the giant emperor penguin arrives and makes an epic trek inland to breed. The mothers soon return to the sea leaving the fathers to hold the eggs and endure the coldest winter on earth.
As the Ganges nears the sea, it joins its mightiest tributary the Brahmaputra, creating a vast flood-prone delta. Here the bustling cities of Calcutta and Dhaka meet the wetlands, home to giant lizards and snakes, huge mean-eating crocodiles and forests full of monkeys. This is a story of human life persisting in wildly variable conditions in a domain that is still the preserve of the royal Bengal tiger.