Christopher Joyce

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KELLY MCEVERS, HOST:

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ARI SHAPIRO, HOST:

Climate scientists agree that this century is getting much warmer and that such warming will likely bring economic pain to the U.S., but economists aren't sure how much. Now, a team of scientists and economists, writing in the upcoming issue of the journal Science, says it can at least tell which parts of the country are likely to suffer the most.

One of nature's most efficient life-support systems is the egg. Eggs evolved over 300 million years ago as vertebrate animals adapted to living on land. And since then, they've taken on numerous shapes, especially among birds.

Biologists have long wondered why there are so many shapes, and what determines each one. Hummingbirds, for example, have eggs like Tic Tacs. Birds called murres produce eggs shaped like big teardrops. Some eggs are more like pingpong balls.

Now, an international team of scientists believes it has solved the mystery of the eggs.

A team of European and Moroccan scientists has found the fossil remains of five individuals who they believe are the most ancient modern humans (Homo sapiens) ever found.

In a remote area of Morocco called Jebel Irhoud, in what was once a cave, the team found a skull, bones and teeth of five individuals who lived about 315,000 years ago. The scientists also found fairly sophisticated stone tools and charcoal, indicating the use of fire by this group.

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RACHEL MARTIN, HOST:

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ROBERT SIEGEL, HOST:

I'm Robert Siegel in Washington where President Trump announced that he is withdrawing the United States from the Paris climate agreement.

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SCOTT SIMON, HOST:

For 51 years, a small federal program has been paying scientists to keep American waterways healthy. It's called Sea Grant — part of the National Oceanic and Atmospheric Administration — and President Donald Trump"s proposed budget for next year would eliminate it.

There are thousands of parks, refuges and wilderness areas in the U.S. that are kept in something close to their natural state. But one form of pollution isn't respecting those boundaries: man-made noise.

New research based on recordings from 492 protected natural areas reveals that they're awash in noise pollution.

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