This episode focuses on the Jurassic period, a time when the first giant killers stalked the Earth and lurked in the seas; a time when the slightest advantage meant the difference between life and death. In North America the iconic allosaurus, an ambush hunter with a lethal bite, dominated. Not even the heavily-armoured stegosaurus was safe from this killer, and incredible evidence reveals a glimpse of a vicious battle between these two giants. Life in Jurassic oceans was no easier; in 2008, a fossil was dug out of a frozen island high in the Arctic. It was a colossal marine reptile, twice as big as most ocean predators, at 15 metres long and weighing about 45 tonnes. This was Predator X. Its skull alone was nearly twice the size of a tyrannosaurus rex's, and its bite force unmatched by anything in the Jurassic seas. The balance of power between predator and prey is a fine one, as prey continually evolves different ways to avoid predators. But for the most successful and enduring predators, the battle to survive has always been tipped in their favour

Having explained the science behind global warming, and addressed the arguments of the climate change sceptics earlier in the series, Dr Iain Stewart concludes the series by looking at the biggest challenge now facing climate scientists - Just how can they predict exactly what changes global warming will bring?
It's a journey that takes him from early attempts to model the climate system with dishpans, to supercomputers, and to the frontline of climate research today: Greenland. Most worryingly he discovers that scientists are becoming increasingly concerned that their models are actually underestimating the speed of changes already underway.

For more than 80 years, Solenopsis Invicta has been on a ceaseless march across the United States, racking up six billion dollars every year in crop damage, equipment repair, and pest control. They have conquered more than 320 million acres in 13 states and killed at least 80 people. And the invader is still on the move. Globally. Now, scientists are cracking the ant's ancient secrets to success and breeding winged assassins to hunt them down. Stunning 3D macro photography explores the secret world of the fire ant and the cutting-edge research into stopping it

Horses. Powerful, graceful, and thunderously fast. No animal has made a greater impact on society or given humans more freedom and mobility. In a spectacular adventure, the film unlocks the mystery of the first horse warriors on the vast, grassy plains of Kazakhstan, where horses still roam free, and nomadic herders follow their traditional way of life.
Investigating clues from archaeology and genetics, researchers reveal vivid evidence of the very first horsemen. They also discover warriors who swept across Europe and turn out to be the ancestors of millions today.

The first second of the Universe, the creation of everything when space, time, matter and energy burst into existence. It is the most important second in history, which seals the Universe's fate and defines everything that comes after - including us.

Heart disease is the number one cause of deaths worldwide, killing more than eight million people each year. Cardiac infarction, more commonly known as a heart attack, can happen without warning, killing heart muscle cells immediately. Even if the patient recovers, the damage to their heart may not.
But there are researchers frantically working to change that. Meet the people inventing the future of cardiac health, from new ways of imaging the body, to the possibility of 3D printing a functioning heart.