Since the 1930s, Louisiana has lost roughly as much land as makes up the state of Delaware.
"If you put the state of Delaware between New Orleans and the ocean, we wouldn't need any levees at all," says John Barry, vice president of the Southeast Louisiana Flood Protection Authority-East. "There is this large buffer of land that has disappeared, and that buffer makes New Orleans much more vulnerable to hurricanes."
If you want to protect rare species, first you have to find them. In the past few years, biologists have developed a powerful new tool to do that. They've discovered that they can often find traces of animal DNA in streams, ponds — even oceans.
The idea took root just five years ago, when biologists in France found they could detect invasive American bullfrogs simply by sampling pond water and looking for an exact genetic match to the frogs' DNA.
In general terms, there are two eras that characterize the 200,000 years or so of human presence on Earth: first, and for most of this time, the hunter-gatherers, nomadic groups that roamed the land in search of food and shelter. Then came what we call "civilization," product of the fixation of larger groups around fertile areas. Presumably, the first were the Natufians some time around 10,000 BCE, along the swath of land between Israel and Jordan.
Professor William Barklow was on vacation when this happened. He was in Tanzania sitting on a river bank gazing about, when all of a sudden a hippopotamus pushed its head out of the river right in front of him, opened its huge mouth and bellowed.
It was really loud. Barklow could feel sound waves hitting his chest, his neck; he could hear the cry echoing along the riverbank. He knew next to nothing about hippos being himself a bird man, a specialist on the North American loon, but he was intrigued by what happened next.
The racial wage gap in the United States — the gap in salary between whites and blacks with similar levels of education and experience — is shaped by geography, according to new social science research.
The larger the city, the larger the racial wage gap, according to researchers Elizabeth Ananat, Shihe Fu and Stephen L. Ross, whose findings were recently published by the National Bureau of Economic Research.
When they come — and they are coming — will the robots we deploy into human culture be capable of evil? Well, perhaps "evil" is too strong a word. Will they be capable of inflicting harm on human beings in ways that go beyond their programing?
While this may seem like a question for the next installment of The Terminator franchise (or The Matrix or whatever, pick your favorite), it's a serious question in robotics and it's being taken up by researchers now.
This week, NASA is trying to do its part to raise science literacy. To give people a better understanding of Earth's position in the solar system, the agency's posted a picture of our planet taken from a billion miles away, give or take 100 million miles or so. And joining me now to talk about the picture, and why NASA took it, is NPR's Joe Palca. Joe, good to see you.
The line to see the thing that was supposed to smell like rotting flesh wrapped around the U.S. Botanic Garden in Washington, D.C., on Monday night. Most folks who braved the heat and hourlong wait weren't greeted with the overwhelming stench of death, but rather the smell of sweat and intense, intense humidity.