About 340 million years ago a brand new family of animals was evolving in the primeval swamps. They were to go one step further than the amphibians who had emerged onto dry and before them. For they would eventually completely cut their ties with water. They were the ancestors of todays lizards. They evolved scaly impermeable skins and moved up into the forests. They diversified into a multitude of different shapes and sizes. They developed signalling systems to communicate with one another. And they squabbled as animals do. For food they hunted insects that were already well established on the land in great numbers. And here without returning to water they produced their families. They powered their bodies not only with food but with the heat that they drew directly from the sun.
As they diversified so they spread into the harshest of the lands habitats. The baking waterless deserts which eventually they would come to dominate. Discover jacky lizards that wave, wrestling beaded lizards and the the world's smallest chameleon, which is no bigger than his thumbnail, and the biggest lizard in Australia.

Is mankind alone, or are there aliens out there, either waiting to be discovered, or on their way to find Earth? Professor Brian Cox spends this episode asking such questions, and what he discovers may raise a few eyebrows. He begins by exploring the human race's efforts to find neighbours in outer space, including the launch of two golden discs containing a greeting from Earth in the 1970s; they are still travelling and are now the most distant man-made objects from the planet. Brian also meets members of the Search for Extra-Terrestrial Intelligence, who have been monitoring radio signals for 50 years without success, before discussing the ingredients needed to make an intelligent civilisation with astrophysicist Dr Frank Drake.

A group of Egyptian revolutionaries battle leaders and regimes, risking their lives to build a new society. The Egyptian Revolution has been an ongoing rollercoaster over the past two and a half years. Through the news, we only get a glimpse of the bloodiest battle, an election, or a million man march. At the beginning of July 2013, we witnessed the second president deposed within the space of three years. The Square is an immersive experience, transporting the viewer deeply into the intense emotional drama and personal stories behind the news. It is the inspirational story of young people claiming their rights, struggling through multiple forces: from a brutal army dictatorship willing to crush protesters with military tanks, to a corrupt Muslim Brotherhood using mosques to manipulate voters. Directed by Jehane Noujaim, the film was nominated for the Academy Award and also won three Emmy Awards.

Since the dawn of civilization, humans have wondered who or what created the universe. Religion offers a spiritual answer, but do the latest discoveries in physics show evidence of a transcendent intelligence, or simply that the laws of physics by themselves could have led to the universe in which we live? This episode embarks on a mind-bending scientific search for God, asking physicists and theologians if the seemingly miraculous way the universe has been calibrated to support life is evidence of a creator...whether string theory will eventually be able to rule out the existence of God...why Stephen Hawking says the universe could have been created spontaneously...and how an advanced civilization in another universe could have conceivably created our own.

David Attenborough continues his search for the origins of flying animals, as he charts the rise of new, larger creatures – extinct reptiles that flew on wings of skin, dinosaurs that sprouted feathers to become the ancestors of birds, and gliding mammals that emerged from a life in the trees to dominate the night as bats. His journey spans the globe – from the rainforests of Borneo to see bizarre gliding animals, to China and its new discoveries of dinosaur fossils. Stunning CGI brings to life creatures that disappeared over 200 million years ago, and new filming techniques bring us closer than ever to the secrets of flight itself.

Scientists around the world are asking themselves the same questions. Over the decades the focus on dolphin research has changed from asking 'how intelligent are dolphins?' to 'how are dolphins intelligent?' and we look at research from the world's foremost dolphin experts for the answers.