Menu Close

Why do most organisms live near the surface of the ocean?

Why do most organisms live near the surface of the ocean?

Marine animals breathe air or extract oxygen from the water. Some float on the surface and others dive into the ocean’s depths. There are animals that eat other animals, and plants generate food from sunlight. Because they need sunlight, phytoplankton live in the photic zone.

Why is 90% of the ocean life found in the top layer?

Sunlit Zone: This is the top layer, nearest the surface. It is also called the euphotic zone. Here there is enough light penetrating the water to support photosynthesis. Because photosynthesis occurs here, more than 90 percent of all marine life lives in the sunlit zone.

Where in the oceans do we tend to find the most life?

Explanation: Areas just off of the coast, from the shoreline to the edge of the continental shelf tend to have the most marine life. This area is called the neritic zone. It extends from the intertidal zone to the edge of the continental shelf where the oceanic zone begins.

Where is there more life in the ocean near the surface or down deep?

The question has held for the two decades since, even as humans have explored more and more of the deep ocean. Scientists now estimate that 80 percent of Earth’s species live on land, 15 percent in the ocean, and the remaining 5 percent in freshwater.

What kind of life can be found in the ocean?

The variety and number of invertebrates, animals without a backbone, is truly remarkable. Marine invertebrates include sea slugs, sea anemones, starfish, octopi, clams, sponges, sea worms, crabs, and lobsters. Most of these animals are found close to the shore, but they can be found throughout the ocean.

What kind of life lives in the ocean?

Ocean Life But most of them—95 percent—are invertebrates, animals that don’t have a backbone, such as jellyfish and shrimp. The most common vertebrate (an animal with a backbone) on Earth is the bristlemouth, a tiny ocean fish that glows in the dark and has needlelike fangs.

Why does about 90% of all marine organisms live in the upper 180m of the ocean?

About 90% of all marine organisms live in the upper 180 m of the ocean. The ocean’s sunlit environment is generally much richer in marine life closer to the continents than is the open sea. Explain why the open sea is sometimes called the “blue desert.”

Why is there little life at the bottom of the ocean?

Answer: Lack of sunlight means no algae or plants to support the food chain, so food is scarce. Deep-sea animals must survive on the decaying scraps of dead organisms from the upper layers of the ocean, which sink to the bottom.

Why is there so little life at the bottom of the ocean?

Why is ocean life so diverse?

“The oceans we see today are filled with a dizzying array of species in groups like fishes, arthropods, and mollusks, not because they had higher origination rates than groups that are less common, but because they had lower extinction rates over very long intervals of time.”

How much life lives in the ocean?

An estimated 50-80% of all life on earth is found under the ocean surface and the oceans contain 99% of the living space on the planet. Less than 10% of that space has been explored by humans.

How does life survive in the deep ocean?

Organisms living in the deep ocean must be adapted to survive under extreme pressure, limited light, cold temperatures, and other factors. This means, for example, at 100 meters (328 feet), you would experience one atmosphere of air pressure and 10 atmospheres of water pressure, for a total of 11 atmospheres.