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Researchers estimate that the bird population has fallen by a quarter since 1970. More than 90% of the loss can be attributed to just a dozen bird families, including sparrows, blackbirds and finches.

Around 20% of U.S. adults live with chronic pain. Medical schools traditionally haven't dedicated much time to teaching about pain and pain control, but one top school now has a mandatory course.

Alternative tests are emerging, the agency says, such as computer modeling and tissue studies of cells grown in the lab. Environmental advocates say the move is too quick, and disregards human health.

A squirrel wondering if it's safe enough to forage for food apparently listens for the reassuring chatter of nearby birds, a study finds.

Historic portraits of revered scientists and doctors can be found all over medical schools and universities — and, as it happens, most feature white men. Some say this sends the wrong message.

The scientists captured the acrobatic jumps of a tiny maggot-like creature with high-speed cameras to figure out how it does this trick with no arms, legs, or wings.

Congress has told the Centers for Disease Control and Prevention not to "advocate or promote gun control." That directive complicates the public health agency's efforts to prevent suicide.

New research shows that young children have a negative reaction to beards, but that changes as they get older. Children with bearded fathers did feel more warmly toward facial hair.

Many shark species tend to congregate in the same areas as industrial fishing ships, a study finds. As a result, tens of millions of sharks in the open ocean end up caught either as food or bycatch.

Many shark species tend to congregate in the same areas as industrial fishing ships, a study finds. As a result, tens of millions of sharks in the open ocean end up caught either as food or bycatch.

Comedy shows on TV often use recorded laughter in combination with a live audience. A new study shows that hearing laughter, especially spontaneous laughter, makes a bad joke seem funnier.

NASA is building its most powerful rocket ever, a moon rocket, which will cost billions of dollars. But the effort has sparked debate about whether NASA should rely on cheaper, commercial rockers.

Fifty years ago, Apollo astronauts collected their first moon rocks. Those samples are still being studied to mine lunar secrets. And scientists are hoping to get access to more of them soon.

The International Space Station is getting older, and NASA is hoping that commercial businesses will take over so that the space agency can focus its efforts on a return to the moon.

The space agency wants to learn more about Titan, an icy body that fascinates scientists because of its similarity to Earth.

Scientists often share their latest research on posters displayed at big conferences. Posters are a long-standing tradition, but one reformer says they're mostly terrible and need to change.

Move over, fruit flies, rats and zebrafish. Squid and octopuses have elaborate brains and behaviors, and scientists say studying them in the laboratory could yield important biological insights.

In the 1970s, Rich Isaacson was presented with what seemed like a crazy idea: using lasers to detect gravitational waves. It became the biggest project the National Science Foundation had ever funded.

Asteroid experts have been simulating a large asteroid heading towards Earth. Friday is the conclusion to the realistic simulation and will reveal how well planetary defense efforts work in this scenario.

A fictitious asteroid is the focus of a realistic exercise, as experts at the Planetary Defense Conference run through how they would respond to news of a looming asteroid strike.