Marine life is organized in the form of a tree, better known as a phylogenetic tree, where each branch, called a phylum, groups together marine species that share common characteristics.

In turn, the phyla are divided into classes and families.

The different phyla are arranged from the least to the most evolved, meaning that phyla containing the least evolved marine species are represented by the lower branches of the tree, while those containing the most evolved are found at the higher branches.

Consequently, the higher we climb in the branches of the marine life tree, the more evolved the species become.

If you're looking for information on a specific alga, sponge, shellfish, crab, sea star, sea urchin, sea anemone or fish, we invite you to explore the full range of marine flora and fauna in our marine life guide !

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