What triggered the incredible diversity of life on Earth, and how have complex life forms, including humans, evolved? Is there direction to evolution? And is human intelligence inevitable? This program focuses on evolution's 'great transformations' —among them the development of a standard four-limbed body plan, the journey from water to land, the return of marine mammals to the sea, and the emergence of humans. Driven by a combination of opportunism and a genetic 'toolkit', these astounding leaps forward define the arc of evolution. And they suggest that every living creature on earth today, and every species that has ever existed, is a variation on a grand genetic theme—a member of one, and only one, tree of life

The final episode explores dinosaurs' extraordinary ability to survive. Featured dinosaurs include the bizarre magyarosaurus, which lived in the shadow of the biggest flying animal - hatzegopteryx - and showed an amazing adaptation to island life; and the weird nothronychus, a carnivore that gave up meat eating. This astonishing capacity to evolve into ever more diverse and bizarre forms meant that dinosaurs not only spread throughout the world, but also dominated life upon it for more than 160 million years. It was only an unprecedented extraterrestrial event that finally saw the end of planet dinosaur.

The Tyrannosaurus Rex is known as the king of the dinosaurs, but how did its reign begin? Meet Moros Intrepidus, a 180 lb., deer-sized ancestor to the T-Rex. Learn how the latest in palaeontology can now link this small dinosaur to the 19,000-pound Scotty, the largest T-Rex ever discovered.
We're filling in gaps in the history of well-known dinosaurs and we're finding specimens of even the most famous dinosaur that are telling us new things about their biology, about their growth, about their size, that we didn't know before. We are nowhere at the end of learning about dinosaurs and in generations to come, we will be knowing things about the lives of these ancient creatures that would probably blow our minds.

One animal embodies all that is amazing about survival. It has adapted to wildly varying habitats and evolved unique weapons of survival; its greatest asset is its ferocious bite and it is evolutions ultimate survivor, but what species is it? Find out if a new bear species could be about to evolve before our very eyes.

Female Isisaurus traverse the Deccan Traps to reach their nesting site. A mixed herd of sauropods and Prenocephale navigate a maze of canyons, but are ambushed by a pack of Velociraptor and a trio of Tarbosaurus. A colony of male Corythoraptor protect their eggs from the scorching sun by day, and a female Kuru kulla at night, who has offpsring of her own.
Trudging through a scorching desert, two young Tarchia find relief at an oasis and encounter an adult twice their size, ready to lay claim. Several Isisaurus hatchlings fall prey to Rajasaurus in an attempt to reach their ancestral home.

Survival of the fittest: Raw competition? Intense cooperation? Both are essential. Interactions between and within species are among the most powerful evolutionary forces on Earth, and understanding them may be a key to our own survival.