Poriferans (phylum Porifera) are sponges. These aquatic, asymmetrial animals are also sessile (unlike most animals). They are simple creatures, having no tissues. Jellyfish, hydra, coral, and sea anemones belong to phylum Cnidaria.

Buttercups

Sea anemones are classified as being animals, but two new genetic studies have found that these water-dwelling creatures are technically half plant and half animal.

Sea Anemones Are Half-Plant, Half-Animal, Gene Study Finds The sea anemone is an oddball: half-plant and half-animal, at least when it comes to its genetic code, new research suggests.

At least half of Earth’s oxygen comes from the ocean. Scientists estimate that 50-80% of the oxygen production on Earth comes from the ocean. The majority of this production is from oceanic plankton — drifting plants, algae, and some bacteria that can photosynthesize.

A Future Without Corals Without corals and the ocean species that rely on them, the ecosystem crashes, and a seaweed-dominated ecosystem takes its place. Once coral reefs disappear, we will lose everything they provide, including marine biodiversity, productive fisheries and potential source of medicines.

Despite their importance, warming waters, pollution, ocean acidification, overfishing, and physical destruction are killing coral reefs around the world. Genetics is also becoming a larger area of coral research, giving scientists hope they might one day restore reefs with more heat tolerant coral.

the Great Barrier Reef

Here are five of the biggest challenges our oceans face, and what we can do to solve them.

• Climate change. Climate change arguably presents the greatest threat to ocean health.
• Plastic pollution.
• Sustainable seafood.
• Marine protected areas.
• Fisheries subsidies.

Global warming is causing sea levels to rise, threatening coastal population centers. Many pesticides and nutrients used in agriculture end up in the coastal waters, resulting in oxygen depletion that kills marine plants and shellfish.

Globally, 100,000 marine mammals die every year as a result of plastic pollution. This includes whales, dolphins, porpoises, seals and sea lions. There are two principle ways that encountering marine debris can be fatal for these creatures: ingestion (eating) or entanglement in plastic-based fishing gear.

Humans Eating Plastic – Over 40 Pounds In A Lifetime.

Plastic Pollution By Country 2021

• China. Based on information from 2010, China produced the largest quantity of plastic at 59.08 tons of plastic.
• United States. The United States is the second-largest producer of plastic waste in the world.
• Germany.
• Brazil.
• Japan.
• Pakistan.
• Nigeria.
• Russia.