Marine phycology deals with the scientific study of algae living exclusively in marine ecosystems. Majority of algae are eukaryotic, photosynthetic organisms that thrive in moist habitats. They are simpler plant species which differ from the higher plants by being deficient in true roots, stems or leaves.
Marine biology is the scientific study of marine life, organisms in the sea. 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.
Lamouroux and William Henry Harvey to create significant groupings within the algae. Harvey has been called "the father of modern phycology" in part for his division of the algae into four major divisions based upon their pigmentation.