Ocean Larvaceans as complex and airy as a thought: Particle flow filmed.

Stunning up-close underwater imagery of a life form new to me. (Ignore the sound track).
From Wikipedia:

Larvaceans (Class Appendicularia) are solitary, free-swimming tunicates found throughout the world's oceans. Like most tunicates, appendicularians are filter feeders. Unlike most other tunicates, they live in the pelagic zone, specifically in the upper sunlit portion of the ocean, or sometimes deeper. They are transparent planktonic animals, generally less than 1 cm (0.39 in) in body length,