Some 500 years after Columbus first encountered cocoa beans, scientists are discovering new, wild cacao flavors in the Amazon rainforest. Turns out, we've barely begun to sample the many flavors nature has to offer.

Under most laws, young people are recognized as adults at age 18. But emerging science about brain development suggests that most people don't reach full maturity until the age 25. Guest host Tony Cox discusses the research and its implications with Sandra Aamodt, neuroscientist and co-author of the book Welcome to Your Child's Brain.

Imagine the U.S. government saying to the people living around Yellowstone, "You know what? All those wild animals in the park — the grizzlies, the bison, the wolves — they belong to you." This is exactly what the government of Namibia has done in a radical experiment to save wildlife — and the people who share their land.

It's known as the Viagra of the Himalayas, and it can cost as much as $50,000 a pound. The world's most expensive fungus is known in Tibetan as yartsa gunbu and has become a status symbol in China.

It's time to celebrate millimeters, kilograms, liters and hectares! it's National Metric Week, and the U.S. stands almost alone in its lack of affection for the Système international d'unités. Serious repercussions have resulted; just ask NASA about their Mars Orbiter.

Plans for a bio-defense animal laboratory at Fort Detrick have scientists and lawmakers concerned for the community's safety.

Many migratory birds travel thousands of miles every year, over land and sea and, sometimes, through hurricanes. Host Scott Simon talks to Dr. Bryan Watts from the College of William and Mary, who used satellite transmitters to track shorebirds as they flew through Hurricane Irene.

NASA gives us a look at the center of the galaxy, in the form of an infrared image that penetrates the dust clouds that obscure the core in the visible spectrum. The result shows "the glow of hot hydrogen in space," the space agency says.