When sick, Nile tilapia seek warmer water. That behavioral fever triggers a specialized immune response, hinting the connection evolved long ago.

High radiation during a time of frenzied star formation in the Milky Way left one stellar population with few chances to form planets, a study reports.

As wildfires burn the landscape, they prime slopes for debris flows: powerful torrents of rock, mud and water that sweep downhill with deadly momentum.

Genetic analyses have solved the riddle of where a marsupial mole fits on the tree of life: It’s a cousin to bilbies, bandicoots and Tasmanian devils.

When Trump’s move to leave WHO takes effect in a year, it may gut funding for global public health and limit U.S. access to crucial data, experts warn.

A Jurassic pterosaur fossil, known to paleontologists for over 160 years, isn’t a new species. It is an odd specimen of Rhamphorhynchus muensteri.

Thanks to climate change, thawing permafrost in the Canadian Arctic has revealed the buried remnant of a glacier that’s 770,000 years old.

The first study of copycat urination in an animal documents how one chimpanzee peeing prompts others to follow suit. Now researchers are exploring why.

Even as firefighters are starting to gain ground on the devastating wildfires in Los Angeles, residents there are just beginning to grapple with the emotional trauma of the disaster. The fires ...

If cigarettes contained very little of the chemical that keeps people smoking, it could help smokers move away from these deadly products. That’s the rationale behind a new rule proposed on ...

It’s a pivotal moment for nuclear weapons. Tensions between the United States and Russia, the two major nuclear powers, are high. Longstanding nuclear pacts have crumbled. China, which trails ...