We float along the river of time. But does that river have a source? Where did time come from? Some believe time and space are one thing, and the Big Bang started the cosmic clock. Others believe the universe existed for almost half a million "years" before light could move and time began. Still others say time is older than our universe. But what if time itself is an illusion? Incredible new experiments may hold the answer. One groundbreaking experiment gives us the power to punch holes in time…and another may create a machine that operates outside time’s boundaries!
We are all at the mercy of the Sun. Its glowing disc sustains nearly all life on Earth. But the Sun also holds a dark secret: someday, our aging, expanding star will bathe the Earth in a fiery holocaust. Everything we know will turn to hot, bubbling, plasma.
It's called the speed limit of the universe. Einstein blew all of our minds when he worked out the Theory of Relativity, and showed that space and time were malleable substances. He also theorized that we as humans can never travel faster than the speed of light, which leaves the stars and other galaxies almost impossibly out of our reach. But the dreams of Star Wars and Star Trek are not dead. In fact, there could be ways to travel faster than the speed of light - and some of them are already being tested in labs around the world.
Quantum theory, the best explanation of how atoms and anything smaller behave, is so weird even scientists who have mastered it find it baffling. But bit by bit scientists are finding maybe it's not so weird as comparable behavior is discovered in our every day world. It's just that no one noticed before.
Our minds store our entire lives, our memories and our deepest desires. Tell no one, and our thoughts remain our own. But our brains are biological computers. Computer hackers can tamper with our email. Could brain hackers someday be able to rewrite our thoughts?
Our universe seems real. But what if it’s a videogame? Scientists in a variety of fields are taking seriously the possibility that we live in a virtual reality. Maybe the Big Bang was just the moment someone flipped the switch and turned on our universe. Maybe what looks random has already been programmed to happen. If some advanced civilization did design and program our universe, would we ever know? Scientists are looking for glitches in the laws of the universe that may uncover its hidden code.
Death is life's greatest certainty. But that may be about to change. Scientists have discovered an immortal animal that may hold the secret of endless regeneration. They're on the brink of editing our DNA so that we can cure death like a disease. Or is dying necessary for the survival of our species?
2017 • Science
This programme looks at the evolution of fish. They have developed a multitude of shapes, sizes and methods of propulsion and navigation. The sea squirt, the lancelet and the lamprey are given as examples of the earliest, simplest types. Then, about 400 million years ago, the first back-boned fish appeared. The Kimberley Ranges of Western Australia are, in fact, the remnants of a coral reef and the ancient seabed. There, Attenborough discovers fossils of the earliest fish to have developed jaws. These evolved into two shapes of creature with cartilaginous skeletons: wide ones (like rays and skates) and long ones (like sharks).
Losing a parent in the wild can be deadly for young animals, but these orphans got lucky when conservationists stepped in. Meet clouded leopard cub sisters taken in by the Nashville Zoo, a baby wombat raised in an artificial pouch at Tasmania's Bonorong Wildlife Sanctuary, and more.
Mammals' ability to learn new tricks is the key to survival in the knife-edge world of hunters and hunted. In a TV first, a killer whale off the Falklands does something unique: it sneaks into a pool where elephant seal pups learn to swim and snatches them, saving itself the trouble of hunting in the open sea. Slow-motion cameras reveal the star-nosed mole's newly-discovered technique for smelling prey underwater: it exhales then inhales a bubble of air ten times per second. Young ibex soon learn the only way to escape a fox - run up an almost vertical cliff face - and young stoats fight mock battles, learning the skills that make them one of the world's most efficient predators.
In this second episode we travel from January to the March equinox. Kate Humble gets closer to the Sun than she has ever been before, whilst Helen Czerski visits a place that gets some of the biggest and fastest snowstorms on Earth.