Nature rarely hands over her secrets without a fight. Solving our planet's mysteries means doggedly following clues that may only reveal a small part of the story.

The Sargasso Sea is an ocean within an ocean, bounded not by land masses but by a vortex of swirling ocean currents—a place where mats of seaweed drift on the high seas and shelter a unique community of open ocean animals.

Dead whales that sink down to the seafloor provide a feast for deep-sea animals that can last for years. Previous research suggested that such "whale falls" were homes for unique animals that lived nowhere else.

Off the coast of Central California, in the inky darkness of the deep sea, a bright orange metal pyramid about the size of two compact cars sits quietly on the seafloor. Nestled within the metal pyramid is the heart of the Monterey Accelerated Research System (MARS)—the first deep-sea cabled observatory offshore of the continental United States.

Squids are some of the most fascinating and diverse deep-sea animals. In this collection of short video clips, MBARI biologists highlight some of their favorite video clips of deep-sea squids.

Deep-sea animals have evolved a variety of ways of moving through the water. Some are graceful. Some are improbable. But all are fascinating. This new video prepared by MBARI's Video Lab staff shows just a few of these approaches to underwater locomotion.

Suppose you're walking along the beach and you see a jellyfish washed up on the sand. Then you see another and then another. It's a jellyfish invasion! What do you do? Who do you call? If MBARI researcher Steve Haddock has his way, you'll take some photos and maybe a few notes, and send them in to his new Jellywatch website (www.jellywatch.org), to share your discovery with the world.

With dimensions comparable to the Grand Canyon, it's no surprise that Monterey Canyon harbors a variety of different seafloor habitats. But even on the flat, muddy floor of the canyon, animal communities vary considerably, according to a new paper by marine biologists Craig McClain and James Barry.

When most people think about the deep sea, they picture broad expanses of muddy seafloor. However, the majority of deep-sea animals, and perhaps the majority of all animals on Earth, live in the "deep pelagic zone"--the dark waters between the ocean surface and the seafloor.

Creeping slowly across the deep seafloor on long, spindly legs, giant sea spiders are found in many deep-sea areas. But, as with many deep-sea animals, we know very little about how sea spiders live. A recent paper by MBARI-affiliated researchers shows that sea spiders suck the juices out of deep-sea anemones.

Julie Packard was presented with a plaque containing photos of a new species of deep-sea coral that was recently named after her.

A new paper shows that animal communities on the abyssal seafloor are affected in a variety of ways by climate change.

Deep-sea worms have evolved an amazing array of body types and survival strategies. The latest addition to this collection of oddities is a group of swimming worms with small oval sacs of fluid hanging from their bodies, just behind their heads.

New calculations made by marine chemists from MBARI suggest that low-oxygen "dead zones" in the ocean could expand significantly over the next century.

Many animals (including humans) spend a great deal of time selecting and fighting to keep their mates. Octopuses, which tend to be loners, have never been shown to engage in such complicated reproductive strategies. However, a new research paper by MBARI postdoctoral fellow Christine Huffard shows that at least one type of octopus (and probably others) do engage in elaborate "mating games."

Over the last five years, large, predatory Humboldt squid have moved north from equatorial waters and invaded the sea off Central California, where they may be decimating populations of Pacific hake, an important commercial fish.

According to a new study in this week’s journal Science these floating islands of ice—some over 20 kilometers (12 miles) across—are having a major impact on the ecology and chemistry of the ocean around them.

It sounds like a junior high school riddle—"What lives 3,000 feet below the ocean surface, is about the size of a marble, and looks like the back side of a pig?" MBARI biologist Karen Osborn and her colleagues recently came up with an answer to this riddle by combining modern DNA analysis with traditional methods of scientific observation.

On September 17, 2006, researchers from NOAA's National Marine Sanctuary program and MBARI will embark on a expedition to study the submerged wreck of the airship USS Macon, the largest and last U.S.-built, rigid lighter-than-air craft.

A unique paper by researchers at MBARI and the Monterey Bay National Marine Sanctuary describes how a deep-sea communications cable affects animals living on and within the seafloor.