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Over the past half-century, North America has lost more than a quarter of its entire bird population, or around 3 billion birds.

That's according to a new estimate published in the journal Science by researchers who brought together a variety of information that has been collected on 529 bird species since 1970.

When a rocket carrying the first module of the International Space Station blasted off from Kazakhstan in November of 1998, NASA officials said the station would serve as an orbiting home for astronauts and cosmonauts for at least 15 years.

The brains of dead pigs have been somewhat revived by scientists hours after the animals were killed in a slaughterhouse.

The Yale University research team is careful to say that none of the brains regained the kind of organized electrical activity associated with consciousness or awareness. Still, the experiment described Wednesday in the journal Nature showed that a surprising amount of cellular function was either preserved or restored.

Suicide rates have increased in nearly every state over the past two decades, and half of the states have seen suicide rates go up more than 30 percent.

Suicide is a major public health issue, accounting for nearly 45,000 deaths in 2016 alone. That is why the Centers for Disease Control and Prevention in Atlanta decided to take a comprehensive look at suicides from 1999 to 2016.

Government health agencies have spent more than two decades shying away from gun violence research, but some say the new spending bill, signed by President Trump on Friday, will change that.

That is because, in agency instructions that accompany the bill, there is a sentence noting that the Centers for Disease Control and Prevention has the authority to conduct research on the causes of gun violence.

Having police officers wear little cameras seems to have no discernible impact on citizen complaints or officers' use of force, at least in the nation's capital.

That's the conclusion of a study performed as Washington, D.C., rolled out its huge camera program. The city has one of the largest forces in the country, with some 2,600 officers now wearing cameras on their collars or shirts.

For the first time, scientists have caught two neutron stars in the act of colliding, revealing that these strange smashups are the source of heavy elements such as gold and platinum.

The day of the long-awaited coast-to-coast solar eclipse has arrived — and if history is any guide, it's likely that somebody's eyes are going to get hurt.

A small, faint star relatively close by is home to seven Earth-size planets with conditions that could be right for liquid water and maybe even life.

The discovery sets a record for both the most Earth-size planets and the most potentially habitable planets ever discovered around a single star.

Last year, global warming reached record high temperatures — and if that news feels like déjà vu, you're not going crazy.

The planet has now had three consecutive years of record-breaking heat.

President-elect Donald Trump intends to nominate Oklahoma Attorney General Scott Pruitt to head the Environmental Protection Agency, announcing his decision in a statement Thursday.

As attorney general, Pruitt has made no secret of his disdain for the EPA.

A potentially habitable planet about the size of Earth is orbiting the star that is nearest our solar system, according to scientists who describe the find Wednesday in the journal Nature.

Scientists have discovered the fossilized remains of an unusual human-like creature that lived long ago. Exactly how long ago is still a mystery — and that's not the only mystery surrounding this newfound species.

The bones have a strange mix of primitive and modern features, and were found in an even stranger place — an almost inaccessible chamber deep inside a South African cave called Rising Star.

Rip open a little package of baker's yeast from the supermarket, peer inside, and you'll see your distant cousin.

That's because we share a common ancestor with yeast, and a new study in the journal Science suggest that we also share hundreds of genes that haven't really changed in a billion years.

Edward Marcotte, a biologist at the University of Texas at Austin, knew that humans and yeast have thousands of similar genes. But, he wondered, how similar are they?

As space shuttle Atlantis orbits the Earth on NASA's last shuttle mission, it's worth remembering that key parts of this high-tech spaceship were handmade by people back here on Earth.

Five years ago, NPR profiled a few of the workers who make pieces of NASA's shuttles, using everyday tools like sewing needles and X-ACTO knives. With the shuttle program ending, NPR revisited those people to see how their lives are changing now that the shuttles will no longer need them.