Marine Biology

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Marine Biology is the study of marine, also called otherwise as aquatic animals, about their life cycle, activities, different facts related to the marine aquatic ecosystem along with its habitats, and their interactions with the environment. It is said that in biology, many families, genera, phyla have a few species living in the sea, and others living on land and marine biology classifies species depending on the environment rather than based on taxonomy.

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Charles Darwin is suitably the best known for his evolution theory, and James Cook is best known as the father of marine biology or modern marine biology. He also performed several significant research to advance the study of marine biology during the 18th Century, which encouraged other scientists also in their inventions.

What is Marine Biology?

Marine biology is the marine ecosystem's scientific study, including various types of tidal zones, saltwater swamps, oceans, mangroves, rivers, streams, and so on along with their features, depth of the ocean beds, various types of marine life, which primarily involves a vast number of species, from the zooplankton and microscopic phytoplankton to massive organisms such as aquatic plants, various types of fish, sharks, and whales that survives, lives, and exists, under the surface of the ocean. Overall, in addition, Marine biology also includes the study of the inter-relationship between ecology, environment, and marine life.

The study of Marine biology explains a wide range of adaptations that involve the physiological, structural, life cycle, and behavioural adaptations of marine habitats. The taxonomy records say that marine habitats are older than terrestrial habitats, as life originated in the oceans was around 3.1 billion to 3.4 billion years ago.

Why is Marine Biology Important?

As the growing global population agitating our society's ability to produce food, water, shelter, and we will continue to look at the oceans to help sustain our basic needs.

Technology advances, added with demand, will improve our ability to derive food, energy sources, drinking water, transportation, and waste disposal from the ocean.

It will be up to the present and future generations to build upon our existing ocean knowledge and its potential to help meet the world's needs and its inhabitants.

Marine Biology vs. Biological Oceanography

The difference between these two terms, "marine biology" and "biological oceanography" is subtle, and are often used interchangeably. Marine biology is the marine species' study that lives in saltwater environments and in oceans. Biological oceanography also studies marine species, but only in the oceanography context. So a marine biologist might study the reproductive behavior of anchovies, where biological oceanographers might study the impact of cold upwellings on anchovy populations off the coast of South America.

Marine Life

Microscopic Life

Inhabitants, as the largest environment on Earth, marine microbial systems drive changes in every global system. Microbes are primarily responsible for all the photosynthesis that virtually occurs in the ocean, and the cycling of carbon, phosphorus, nitrogen, and many other nutrients and trace elements as well.

Incredibly the microscopic life undersea is diverse and still understood poorly. For suppose, the virus's role in the marine ecosystems is being explored barely even at the beginning of the 21st Century.

The phytoplankton role is understood better due to its critical position as the most numerous primary producers on Earth. Phytoplankton is divided into cyanobacteria (also known as blue-green bacteria/algae), different types of algae (red, brown, yellow-green, and green), diatoms, euglenoids, dinoflagellates, coccolithophorids, cryptomonads, chlorophytes, chrysophytes, silicoflagellates, and prasinophytes.

Plants and Algae

Microscopic algae and plants give important habitats for life and sometimes act as a hiding place for invertebrates for larval forms of larger fish and foraging places.

Algal life is very diverse and widespread under the ocean. Microscopic photosynthetic algae contribute a bigger proportion of the world's photosynthetic output compared to all the combined terrestrial forests. Actually, most of the niche occupied by sub plants on land is occupied by macroscopic algae in the ocean, like Sargassum and kelp, which are usually known as seaweeds, which create kelp forests.

Plants surviving in the sea are often found in shallow waters, like the seagrasses (examples of which are Zostera, eelgrass, and Thalassia, turtle grass). These plants have adapted to the high range of salinity of the environment of the ocean. Also, the intertidal zone is a good place to find plant life in the sea, where cordgrass or mangroves or beach grass might grow.


Invertebrates make up a considerable portion of all life in the sea as on land. Invertebrate sea life involving Cnidaria like the sea anemones, jellyfishes; sea worms including Nemertea, Echiura, phyla Platyhelminthes, Sipuncula, Phoronida, and Chaetognatha; Mollusca including shellfish, squid; Ctenophora; Arthropoda including Crustacea and Chelicerata; Bryozoa; Porifera; Echinodermata including starfish; and Urochordata including tunicates or sea squirts. The invertebrates have no backbone, and there are over a million species count.

FAQ (Frequently Asked Questions)

1. Explain the Marine Habitats?

Ans. Marine habitats can be further divided into:

  • Coastal Habitats

  • Open Ocean habitats

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Coastal habitats are found in the extended area from the shoreline to the edge of the continental shelf. Most marine life is appeared to found in coastal habitats, even though the shelf area occupies only 7% of the total ocean area.

Whereas the Open ocean habitats are happened to found in the deep ocean, beyond the edge of the continental shelf. Marine habitats alternatively can be divided into demersal and pelagic habitats. Demersal habitats stay near or on the bottom while the Pelagic habitats are found in the open water column or near the surface, away from the bottom of the ocean, and affected by ocean currents.

2. Mention a few differences between Marine Biology and Marine Science?

Ans. Marine Biology is importantly a subdiscipline of Marine Science. Marine Biology covers mostly living organisms, and they are found generally in marine systems. It does not fully address the physical and chemical aspects of the oceans, like climate, currents, tidal effects, wave action, and so on, except in relation to how these things affect the biological organisms directly. Marine Science essentially covers everything from marine biology, marine chemistry, marine ecology, marine geology, and more related fields. Marine Science is a much-encompassing field, and also Marine Science is more marketable.