From the food on our tables to the fuel in our cars, crude oil seeps invisibly into almost every part of our modern lives. Yet many of us have little idea of the incredible journey it has made to reach our petrol tanks and plastic bags from its origins millions of years ago.
Our planet was once populated by megafauna, big top-of-the-food-chain predators that played their part in balancing our ecosystems. When those megafauna disappear, the result is a "trophic cascade," where every part of the ecosystem reacts to the loss. How can we stay in balance? George Monbiot suggests rewilding: putting wolves, lions and other predators back on top -- with surprising results.
In which John Green and Hank Green teach you about how human primates moved out of Africa and turned Earth into a real-life Planet of the Apes. And the apes are people! John and Hank teach you about how humans evolved, and the sort of tricks they picked up along the way like complex tool use, big brains, and fighting. Learn more: http://www.bighistoryproject.com
Is it possible that plants are smarter than we think? They are among the world's oldest and most successful organisms and represent some of the strangest and longest living life forms on the planet. Stunningly diverse, plants have served us in many critical ways, from providing food, shelter and clothing to life-saving medicine. And yet we know very little about them. A luscious exploration of the natural world, Smarty Plants effortlessly integrates pioneering science with a light hearted look at how plants behave, revealing a world where plants are as busy, responsive and complex as we are. From the stunning heights of Utah's Great Basin Desert to the rainforests of Canada's west coast, Smarty Plants follows lead scientist and ecologist JC Cahill as he treks the green world and discovers that plants are a lot more like animals than we ever imagined. The world he reveals is one where plants eavesdrop on each other, talk to their enemies, call in insect allies to fight those enemies, recognize their relatives and nurture their young.
Sharks are among the most misunderstood predators on the planet, but an international team of scientists is trying to change that. Their research is revealing that sharks can be sociable and intelligent, and they could even help solve some of the toughest medical challenges of the 21st century. However, their breakthroughs come just as many sharks face extinction. Science may now be the only way to save them.
Human mothers raise fetuses inside their wombs and breast feed their babies for a long time after birth. What made humans evolve so that we raise our children so affectionately? The latest research reveals an unexpected origin of mothers' affection toward their children. Scientists believe that our ancestors experienced unforeseen dramatic changes in DNA under threats of extinction. These DNA changes caused humans to be devoted to raising children. Learn about the scientific interpretation of the evolutionary roots of your affectionate bonds with your kids.
The episode begins in the South American rainforest whose rich variety of life forms is used to illustrate the sheer number of different species. Since many are dependent on others for food or means of reproduction, David Attenborough argues that they couldn't all have appeared at once. He sets out to discover which came first, and the reasons for such diversity. He starts by explaining the theories of Charles Darwin and the process of natural selection, using the giant tortoises of the Galapagos Islands (where Darwin voyaged on HMS Beagle) as an example. Fossils provide evidence of the earliest life, and Attenborough travels a vertical mile into the Grand Canyon in search of them.