Why they're awesome: The largest animal on Earth is thought to be the blue whale, but these strange sea creatures can grow ...

Not only is it not a jellyfish, it's not even an "it," but a "they." The Portuguese man-of-war is a siphonophore, an animal made up of a colony of organisms working together. The man-of-war ...

The siphonophore is known as Rhizophysa eysenhardtii. Siphonophores are fascinating marine organisms belonging to the phylum Cnidaria, which includes jellyfish, corals, and sea anemones.