Video: Gulf of Mexico jellyfish swarms

Jellyfish swarms in the Gulf of Mexico can be 100 miles (160 km) long. At their thickest, there can be more jellyfish than there is water.

Diverse microbes found deep beneath Antarctic ice sheet

Nearly 4,000 species of microorganisms were found in the cold, dark waters of Lake Whillans, which sits about half a mile below Antarctica’s ice sheet.

Large section of Aral Sea completely dried up for first time in modern history

The Aral Sea - once the fourth largest inland sea in the world - has been shrinking markedly since the 1960s. Now its eastern basin has completely dried.

35,000 walrus come ashore in Alaska

Pacific walrus that can't find sea ice for resting in Arctic waters are coming ashore in record numbers on a beach in northwest Alaska.

Lifeform of the week: Fishing cats

Boldly going where few cats have gone before: into the water.

2014 State of the Birds report: Mixed marks for U.S. birds

While some wetland birds in the U.S. appear to be doing well because of conservation programs, other birds are experiencing steep declines in population numbers.

California drought linked to climate change, say scientists

Stanford researchers report that the drought now crippling California is likely linked to human-caused climate change. Other researchers disagree.

World population unlikely to stabilize in this century

Experts used “scenarios” to suggest global human population will stabilize around 9 billion by about 2050. A new statistical analysis tells a different story.

Clues to the rapid rise of birds

"There was no moment in time when a dinosaur became a bird, and there is no single missing link between them," said Steve Brusatte, who led the study.

The water in your bottle might be older than the sun

Up to half of the water on Earth and throughout our solar system likely originated as ices that formed in interstellar space.