Gallery: You Know Who Has to Deal with Rio’s Toughest Event? Horses

Seven of 16 planetary vital signs are in their most extreme state ever recorded, and El Niño is here to make matters even worse.

Here’s what we know about the record-setting El Niño on a record-hot planet, and the most important questions scientists are trying to answer.

Tropical Storm Isaias is set to become the basin’s first hurricane of the season, bringing life-threatening rain and storm surge to the Gulf Coast.

Warhound came out of stealth on Wednesday with $200 million in funding and a mission to create “elite working dogs” equipped with "advanced body armor."

As coastlines change, so do surf breaks. That may spell the end for premier waves and the tourist economies that depend on them.

Redwoods adapted to a cool, foggy climate. Now a new study shows they slow down photosynthesis when their environment warms.

The comedian sees being online as similar to visiting the zoo. “I don’t need to interact with that,” he says. “It’s just a thing that I enjoy, and then I walk away.”

The death of a lab worker in Russia has authorities looking at whether plague played a role. Even if it did, though, the odds of it spreading are very low.

Two orbiters have long outlasted their expected lifespans and completely reshaped our understanding of the Red Planet, all while operating 140 million miles from Earth.

Although the case is considered exceptional, investigators are working to determine how the infection occurred and whether the pathogen played a role in the patient’s death.