Moving on to Ethiopia 3.2 million years ago, we witness the beginnings of mankind via a group of australopithecus - a type of ape which, like us, walks upright on two legs. But unlike us, these early members of the human family weren't predators, they were prey. Things get worse for the group as they are hunted by a sabre-tooth cat called dinofelis and fall victim to other dangers such as malaria, rival australopithecus and a rampaging 14-tonne deinotherium.

The First Amendment and the very idea of free speech are under attack in America today. A growing number of Americans don't believe you have the right to speak your mind if what you have to say might offend someone, somewhere. They advocate for 'safe spaces' in which people won't be offended by ideas they may find troubling. But is that what America is about?
In No Safe Spaces, comedian and podcast king Adam Carolla and radio talk show host Dennis Prager travel the country, talking to experts and advocates on the left and right, tour college campuses, and examine their own upbringings to try to understand what is happening in America today and what free speech in this country should look (and sound) like.

In the summer of 1983, just days before the birth of his first son, writer and theologian John Hull went blind. In order to make sense of the upheaval in his life, he began keeping a diary on audiocassette. Upon their publication in 1990, Oliver Sacks described the work as 'the most extraordinary, precise, deep and beautiful account of blindness I have ever read. It is to my mind a masterpiece.'
With exclusive access to these original recordings, Notes On Blindness encompasses dreams, memory and imaginative life, excavating the interior world of blindness.

Mathematician Dr Hannah Fry explores the mystery of maths. It underpins so much of our modern world that it's hard to imagine life without its technological advances, but where exactly does maths come from? Is it invented like a language or is it something discovered and part of the fabric of the universe? It's a question that some of the most eminent mathematical minds have been wrestling with. To investigate this question, Hannah goes head first down the fastest zip wire in the world to learn more about Newton's law of gravity, she paraglides to understand where the theory of maths and its practice application collide, and she travels to infinity and beyond to discover that some infinities are bigger than others.
In this episode, Hannah goes back to the time of the ancient Greeks to find out why they were so fascinated by the connection between beautiful music and maths. The patterns our ancestors found in music are all around us, from the way a sunflower stores its seeds to the number of petals in a flower. Even the shapes of some of the smallest structures in nature, such as viruses, seem to follow the rules of maths. All strong evidence for maths being discovered. But there are those who claim maths is all in our heads and something we invented. To find out if this is true, Hannah has her brain scanned. It turns out there is a place in all our brains where we do maths, but that doesn't prove its invented.
Experiments with infants, who have never had a maths lesson in their lives, suggests we all come hardwired to do maths. Far from being a creation of the human mind, this is evidence for maths being something we discover. Then along comes the invention of zero to help make counting more convenient and the creation of imaginary numbers, and the balance is tilted in the direction of maths being something we invented. The question of whether maths is invented or discovered just got a whole lot more difficult to answer

The human eye can see extraordinary detail, but the eye of a needle held at arm's length is pretty much at the limit of our vision. Anything smaller is simply invisible, at least to the naked eye. But what if we could see this hidden world all around us in greater detail and magnification than ever before? How different would our familiar surroundings then seem? Richard Hammond explores the astonishing miniature universe all around us, revealing that small is not only beautiful, it can also be very, very powerful. From seeing the microscopic changes to ice crystals that can trigger an avalanche to watching in horror the invisible aftermath of a sneeze on a commuter train and learning how the surface of an ordinary-looking plant hides an astounding secret that will make walking on the moon safer, Richard harnesses cutting-edge technologies to transport the viewer into a spectacular micro realm.

Sagan discusses the story of the Heike crab and artificial selection of crabs resembling samurai warriors, as an opening into a larger discussion of evolution through natural selection (and the pitfalls of intelligent design). Among the topics are the development of life on the Cosmic Calendar and the Cambrian explosion; the function of DNA in growth; genetic replication, repairs, and mutation; the common biochemistry of terrestrial organisms; the creation of the molecules of life in the Miller-Urey experiment; and speculation on alien life (such as life in Jupiter's clouds). In the Cosmos Update ten years later, Sagan remarks on RNA also controlling chemical reactions and reproducing itself and the different roles of comets (potentially carrying organic molecules or causing the Cretaceous–Paleogene extinction event).