Marine biology is the scientific study of living organisms in the ocean or other marine or brackish bodies of water.
World Marine Environment.
Given that in biology many phyla, families and genera have some species that live in the sea and others that live on land, marine biology classifies species based on the environment rather than on taxonomy. Marine biology differs from marine ecology as marine ecology is focused on how organisms interact with each other and environment and biology is the study of the animal itself.
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