Seen up close, each polyp has a tube-like body and an opening ringed with dozens of “transparent” tentacles. These “sand-encrusted” polyps form “small groups embedded and assembled in a common tissue” ...

Among the myriad creatures that populate our ocean, some stand out as having an outsized impact on the marine environment—shaping and maintaining habitats that themselves sustain countless other forms ...

The Portuguese man-of-war is a siphonophore, an animal made up of a colony of organisms working together. The man-of-war comprises four separate polyps. It gets its name from the uppermost polyp ...