Ocean

At least 90 mysterious blobs of underwater jelly have been sighted near Norway and the Mediterranean Sea, and researchers finally know what they are.

Scientists propose that the circling could calibrate the animals' magnetic biosensors, in much the same way as submarines circle.

Every few years, millions of by-the-wind sailor jellyfish wash up on beaches and die. What is causing so many of them to become stranded? The blob could be to blame.

Octopuses can "see" light with their arms, even when their eyes are in the dark, researchers have found.

Two species of sacoglossan sea slugs have been found to be able to sever their heads from their bodies and regrow a replacement by researchers in Japan.

The Gulf Stream, one of Earth's major climate-regulating currents, is flowing slower now than it has in 1600 years. Climate change could kill it.

A new study reveals pirate attacks are more common in waters experiencing destructive and illegal fishing, suggesting the two may be linked.

Scientists recently animated the hazards of being a blue whale that's trying to avoid collisions with ships at sea.

Frequently mistaken for discarded piles of beach trash, ropelike sea whips are a type of colorful coastal coral.

Octopuses sometimes partner with fish to hunt, but the partnership comes with risks (for the fish, that is).

A new species of comb jelly was identified in a deep trench near Puerto Rico.

The Chinese submarine Fendouzhe has completed a months-long expedition to the deepest part of the ocean, a feat matched by only James Cameron, a hobbyist investor and the U.S. Navy.

Before we start mining for precious metals in the darkness of the deep sea, we might try switching on the light first and observing our surroundings.

Researchers found and measured a group of rare Bigfin Squids congregating off the Australia coast for the first time ever.

When mantis shrimp find a burrow that's just right, they'll fight brutal battles to steal it.

Scientists have discovered a free-standing reef near Australia's Great Barrier Reef, which stands taller than the Empire State Building.

A new report finds that microplastic debris is twice as abundant in the deep ocean as it is on the sea surface.

A new study evaluates massive Megalodon alongside all sharks in the lamniform group — living and extinct. Even among its extinct relatives, Megalodon was unequalled in length and mass.

A seven-armed octopus unexpectedly washed ashore on Whidbey Island, Washington, even though these cephalopods aren't native to the area.

However, one expert says we need more proof these organisms actually eat viruses.