The world's largest species of marine algae is giant kelp, which can grow as much as two feet per day from depths of about 100 feet up to the ocean surface.

Despite being multicellular and photosynthetic, organisms such as kelp and sea moss are macroalgae, not plants, because they lack specialized roots and stems to pump water.

Algae can capture carbon dioxide at rates up to 50 times faster than land-based plants and can be grown in tanks that use one-tenth the land footprint of terrestrial plants.

Scientists have collected critical minerals from ocean water using seaweed, a type of algae that leaves behind a mineral-rich powder called bio-ore after being processed into biofuels.

Massive blooms of microscopic algae called dinoflagellates produce the neon blue light seen in glowing tides.

Deep water corals—located throughout the world's ocean basins at depths beyond 200 meters (660 feet)—slowly build small coral gardens in the dark with the help of underwater worms.

Harmful algal blooms can occur in warm, nutrient-rich, stagnant waters and are often associated with the rapid reproduction of blue-green algae—a misnomer for cyanobacteria, not algae.

Over 1 million fish, marine mammals, and invertebrate species depend on coral reefs for habitats, camouflage, and food.

Green algae have lived on Earth for about one billion years, roughly twice as long as the first plants.

The Amazon rainforest is considered the 'lungs of the Earth,' but it contributes less than a quarter of the oxygen of phytoplankton—microscopic plants, algae, and bacteria capable of photosynthesis.

Acetabularia jalakanyakae is one of the largest known single-celled organisms and is nicknamed the 'mermaid's wineglass' for its umbrella-shaped cap.

Molecules derived from algae can be found in foods such as ice cream, salad dressings, brownie mix, and gravies, as well as in products such as toothpaste, multivitamins, and egg substitutes.

The deep-sea fangtooth has the largest teeth of any marine species relative to body size

From transparent fish to the heaviest worms on the planet, these seven creepy creatures lurk in the deep sea. Learn all about them and the unique traits that help them survive and hunt.

Plastic debris across the ocean aids the spread of invasive species

The durable, long-lasting material can serve as a platform for living organisms to latch onto and ride over vast distances. After the 2011 earthquake and tsunami in Japan, a large dock carrying 100 tons of living organisms native to Japan washed up on Oregon's coastline, confirming the ecological threat.

Whale falls—dead whales that have fallen to the ocean's floor—can provide enough food to spawn a local ecosystem of deep-sea organisms that lasts for decades.

The ocean's ability to store carbon long-term is being hindered by marine heatwaves

More than 4,000 robotic floats with biogeochemical data sensors, including oxygen, pH, nitrate, suspended particles, chlorophyll, temperature, and conductivity, have been deployed as part of the Global Ocean Biogeochemical Array. They have identified changes to ecosystem structure affecting the ocean's ability to transport carbon from surface waters into the deep.

The first coral reefs formed hundreds of millions of years ago from the carbonate skeletons deposited by hard corals.

What happens when a whale dies and falls to the ocean floor

A large whale's body can blanket more than 538 square feet of ocean floor. That's an enormous amount of organic matter, providing food for the ecosystem for centuries. Researchers have discovered bones on the seafloor from whale species that have been extinct for over 100,000 years.

Some algae have helped remove microplastics from water after being bioengineered to clump together with these contaminants, forming an easily collectible microplastic-algae sludge.

Carbon sinks absorb more greenhouse gases than they produce

The largest on Earth are oceans, which capture 25% of all carbon emissions and 90% of excess atmospheric thermal radiation while generating half of the world's oxygen. Wildfires and deforestation have reduced forests' net sink capacity, though fungi are believed to capture and store over a third of global carbon emissions.

The world's largest waterfall is in the ocean

In the Denmark Strait between Greenland and Iceland, a series of cataracts descend from 2,000 to 10,000 feet beneath the surface. The underwater waterfall is possible because cold water is denser than warm water and quickly sinks in the region.

The 10 most amazing deep sea creatures

In this video, researchers from the world-renowned Monterey Bay Aquarium discuss the most fascinating deep sea creatures, and how they developed some of their strangest features.

The cells of spotted salamander embryos and early-stage larvae harbor algae that support embryonic development by increasing oxygen levels and removing waste.

The world’s largest waterfall is hidden underwater

The Denmark Strait cataract is an underwater waterfall in the ocean channel between Iceland and Greenland. It’s also the world’s largest waterfall. Standing 11,500 feet tall, the incredible natural landmark is more than three times the height of Angel Falls, the largest waterfall on land. Discover more about the features of this cataract, which, despite its massive size, is totally undetectable above water.

How marine debris accumulates in giant garbage patches

National Geographic breaks down everything you need to know about The Great Pacific Garbage Patch, along with pictures. The Great Pacific Garbage Patch is a collection of marine debris in the North Pacific Ocean. Marine debris is litter that ends up in the ocean, seas, and other large bodies of water.

Aerial photos of red tide off the Gulf Coast

The toxic algae grows naturally in warmer oceans in small amounts and is typically harmless. With extended warm periods and unusually-high additions of nutrients from run-off, the algae blooms extensively, posing health risks to wildlife and humans...

About 1,500 species of tardigrades have been identified by their unique physiology

Freshwater-bound eutardigrades live on mosses and lichens and are distinguished by variations in the shape and number of claws at the end of their legs. Marine heterotardigrades, which live on algae and deep-sea sediments, have been observed to possess feathers, inflatable appendages, and flagpole-like tails.

An analysis of fossilized reefs from northern Africa and Germany suggests that shallow water corals and photosynthetic algae formed the mutualistic partnership seen today between 419 and 359 million years ago.

Feeding grazing cattle seaweed cut their methane emissions by almost 40%

The largest share of the 12% of global greenhouse gas emissions from livestock comes from methane released when cows burp. A study found that introducing a seaweed supplement in pellet form significantly reduced these emissions without affecting cattle's health or weight.

View a gallery of animals found on abyssal plains, hydrothermal vents, seamounts, and other deep-sea habitats.

Meet siphonophores, breathtaking jellyfish-like organisms

Siphonophores are colonial jelly-like creatures made up of specialized segments that work together as one. They're fairly unknown despite being a significant sea predator. Sink into their strange beauty with this video.

What animals live in the ocean?

The oceans host an incredible diversity of fascinating species. Oceana's Marine Life Encyclopedia beautifully presents facts and photos of ocean animals from Atlantic Cod to Zebra Sharks.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

Bioluminescence became common in the ocean to support survival in dark environments

Despite seeming like a rare ability in land animals and unseen in plants, bioluminescence has evolved at least 29 times across marine species, indicating its necessity for survival where hiding spots are rare and highlighting how environments provide evolutionary pressure.

Alaska's Bristol Bay hosts the world's largest self-sustaining wild salmon runs

Nearly 50 million of the fish return to the area each year to spawn, sometimes in the same spot they were born. A journalist tracked the supply chain journey of one sockeye salmon from the sea to the customer's plate.

Watch underwater photosynthesis make water look like champagne

In shallow waters where sunlight can reach, photosynthetic reactions absorb water and dissolved carbon dioxide, producing bubbles of oxygen at the surface of plants. As these bubbles rise to the water's surface, a fizzy appearance is created.

Coral reefs are built by thousands of coral polyps—tiny animals whose mouths both consume food and expel waste.

Biosphere 2 is the largest Earth science experiment ever built

The vivarium—an enclosed system including animals and plants—is sealed from below with 454 metric tons of stainless steel liner and includes an ocean habitat with more than 700,000 gallons of seawater. B2 is visited by 100,000 people yearly, including more than 10,000 K-12 students.

Invasive species are the third biggest threat to Earth's biodiversity

According to the World Wildlife Fund's Living Planet Report 2020, changes in land and sea use account for about half of all recorded threats to the diversity of the planet's species. Species overexploitation is the second-largest proportional threat at 24%, while invasive species make up 13%.

Our favorite visualization of the depths of the ocean and the various animals species within it.

The largest river on Earth is actually in the sky

High above the canopy of the Amazon rainforest drifts an airborne river fed by the towering trees below. The trees pull water from their roots into their trunks, pushing any excess water out of their leaves and into the atmosphere as vapor. Watch this six-minute video to learn how.

What makes the world's biggest waves?

Some of the world’s biggest waves, routinely reaching 100 feet high, are formed near the town of Nazaré, Portugal. But what makes this area so prone to massive swells? While a number of factors are involved, the key feature is the Nazaré Canyon,...

Underwater nighttime photos capture the ocean's diversity

Self-taught photographer Steven Kovacs explores Palm Beach's ocean after sunset, capturing tiny sea creatures in deep waters. Over eight years, he's dived into Florida's eastern coast, drifting from 0 to 100 feet, photographing rarely seen larval fish. Lacking formal marine biology training, Kovacs collaborates globally to identify species like cusk eels and the female blanket octopus, known for its revealing membrane. Check out his photos here.

Data-packed infographic on Earth's oceans

Did you know more than 200 million people live on land that could be flooded by rising sea levels? Learn fascinating facts about the ocean from this data-filled infographic from the Woods Hole Oceanographic Institute.

An interactive of the deep sea

Explore the deepest parts of the ocean

The deeps of the Earth's oceans are some of the most extreme environments on the planet. Take a trip 36,000 feet to the deepest parts of the sea in this informative, 10-minute animated video.

Turning some invasive species into cash crops has helped control their spread

In Mexico, some companies are transforming sargassum seaweed blooms into paper, bricks, and shoes, while in Cambodia, water hyacinths are dried and woven into baskets, rugs, and other crafts. Lionfish and green crabs have been hunted for culinary dishes, with the latter also being used to make crab whiskey in New England.

Watch a time-lapse from space of photosynthesis across Earth

Using NASA satellite imagery, carbon absorption can be tracked and serves as a proxy for photosynthetic activity on land and in the oceans. Over the course of a year, seasonal changes can be observed as plants become dormant in the fall and active again in the spring.

38 thought-provoking facts about the ocean

Coral produces its own sunscreen, tsunamis move at 500 miles per hour, one of the loudest sounds ever recorded came from an ice quake, and other interesting facts collected from sources such as National Geographic and NASA.

See an anamorphic illusion of a massive crashing wave in South Korea

An enormous aquarium with perpetually crashing waves has popped up amidst an urban landscape in South Korea, but don’t expect to hear the water sloshing around if you walk by. Designed by District, the elevated tank is actually a massive anamorphic illusion. The digital media company created the pub

A submarine canyon helps produce the biggest ocean waves in the world

Off the shores of Nazaré, Portugal, the canyon is nearly three times as deep as the Grand Canyon in places. This creates a rare convergence of fast and slow swells that erupt into towering walls of water over 100 feet high.