In the fourth episode, Dromaeosaurs stalk a hadrosaur herd as they cross a freezing river. Male Ornithomimus raid rival nests to bolster their own. Olorotitan raise their offspring on fertile volcanic fields but contend with biting mosquitoes.
Troodontids hunt mammals flushed out by a forest fire. A juvenile Antarctopelta scours the forest for a new winter den. Within the snow-covered forest, a tense standoff develops between ancient rivals, Pachyrhinosaurus and Nanuqsaurus.

Sixty-six million years ago, an asteroid wiped out the dinosaurs in a fiery global catastrophe. But we know little about how their successors, the mammals, recovered and took over the world. Now, hidden inside ordinary-looking rocks, an astonishing trove of fossils reveals a dramatic new picture of how rat-sized creatures ballooned in size and began to evolve into the vast array of species.

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.

This episode explores the palaeogeography of Earth over millions of years, and its impact on the development of life on the planet. Tyson starts by explaining that the lignin-rich trees evolved in the Carboniferous era about 300 million ago, then explains on the nature of plate tectonics that would shape the landmasses of the world and the asteroid impact that initiated the Cretaceous–Paleogene extinction event, leaving small mammals as the dominate species on earth. Earth's landmasses are expected to change in the future and postulates what may be the next great extinction event.

The series ‘Life on Our Planet’ brought to life by Steven Spielberg and narrated by Morgan Freeman, unfolds the remarkable and epic four-billion-year journey of life on Earth. Its captivating narrative explores the continuous battle of life to conquer and survive, delving into the history of the 20 million species that exist today. However, what we witness is merely a snapshot in time; 99% of Earth's inhabitants are buried in our deep past. This series weaves the tales of these dynasties, chronicling their rise and fall in a story that is as incredible as it is enlightening, sparking a profound interest in the history and resilience of life on Earth.
The first episode traces the evolution of life on our planet and highlights the diversity of life, from ancient sharks to the reign of dinosaurs and the emergence of mammals. The episode showcases the constant struggle for survival and adaptation across different eras, illustrating the dynamic and often brutal nature of Earth's evolution.

Moving on to the Late Eocene period 36 million years ago and mammals have prospered and are now the largest creatures on land and sea. This is an era of animals like andrewsarchus, the biggest mammal carnivore ever to walk on land, and the brontotheres, small-brained herbivores. It is in the sea, however, that the most monstrous mammals of all can be found. We follow the fate of a female basilosaurus, a huge serpent-like early whale, but nothing like the gentle filter feeding whales of the 21st century. Four times the length of the great white shark, with jaws to match, she is every inch a killer.