Scientists have long debated whether the Earth's water was here when the planet formed or whether it arrived later. A study suggests much of the water originated in rocks from which Earth is built.

The Food and Drug Administration's chief said Sunday the therapy reduces deaths among COVID-19 patients by 35%. On Monday he apologized, acknowledging that statistic greatly exaggerates any benefit.

Researchers hope the study can provide insight as to how COVID-19 spreads in large stadiums — and how to prevent it.

Doctors are researching why some patients remain unconscious for days or weeks, even after sedating drugs are withdrawn. They also worry that these patients aren't being given time to recover.

The side-by-side tracks of two ancient animals have been called "by far the oldest vertebrate tracks in Grand Canyon."

The coronavirus appears to transmit unevenly: A few people can infect many, while others don't pass the virus on at all. Researchers are working to understand the factors that drive superspreading.

The stripes on zebras have been found to repel flies. But now researchers have found a black-and-white checkered pattern will, too — making them question the optical effect behind the phenomenon.

New research suggests that penguins' ancestors originated not in frozen Antarctica but, instead, off the coasts of Australia and New Zealand, adapting to new climes over 22 million years.

A study out Monday found that Hispanic and nonwhite workers made up 73% of cases associated with workplace outbreaks in certain industries, despite representing 24% of the workforce in those sectors.

To owners of bars and nightclubs, pandemic restrictions on the industry can feel punitive. But there are important differences, virus hunters say, between a bar and a restaurant that serves alcohol.

Researchers at Yale University are seeking emergency use authorization from the Food and Drug Administration for a coronavirus saliva test. This streamlined test can offer results faster and easier.

Contrary to the image of sharks as lone predators, new research has found evidence that some species are social creatures who return repeatedly to the same fellow sharks, often for years.

Scientists found that grey reef sharks in the central Pacific Ocean form social groups — and they say those connections can last for years.

It's the first country to approve a COVID-19 vaccine, but it has not finished Phase III trials to assess safety and effectiveness in the general population.

A new study reveals there were multiple species of Deinosuchus, the giant crocodylians that lived 75 million years ago. They were among the largest predators in the ecosystem and ate dinosaurs.