Aquatic ecosystems support plankton in the form of tiny aquatic animals called zooplankton.
Zooplankton are conveyed by currents, but many species have a means of locomotion. Locomotion is often used by zooplankton to forage and to avoid predatory consumption. Zooplankton move by the paddling of cilia, antennae, and jointed appendages, or by muscle contractions creating jet propulsion.
Zooplankton by Cindy Jo Mendoza |
Light-induced migration of zooplankton in arctic marine environments during winter's absence of sunlight was once believed to be non-existent. Recently marine scientists have observed reflected moonlight and lunation causing predictable zooplankton migration cycles.
"During the permanently dark and extremely cold Arctic winter, these tiny marine creatures, like mythical werewolves, respond to moonlight by undergoing mass migrations."During sunlight-starved winter months, zooplankton use their means of locomotion to travel downward to greater depths on a daily cycle as the moon rises above the horizon. The zooplankton also sink en masse from the surface to depths of about 50 meters (164 ft) every 29.5 days corresponding to the reflected light of the full moon.
― Kim S. Last, Scottish Association for Marine Science
It is believed this downward moonlit journey gives zooplankton the cloak of darkness to avoid predation by carnivorous marine life and birds.
Ctenophores, commonly known as comb jellies source: University of California Museum of Paleontology |
"[...] it is a strange thing that most of the feeling we call religious, most of the mystical outcrying which is one of the most prized and used and desired reactions of our species, is really the understanding and the attempt to say that man is related to the whole thing, related inextricably to all reality, known and unknowable. This is a simple thing to say, but the profound feeling of it made a Jesus, a St. Augustine, a St. Francis, a Roger Bacon, a Charles Darwin, and an Einstein. Each of them in his own tempo and with his own voice discovered and reaffirmed with astonishment the knowledge that all things are one thing and that one thing is all things—plankton, a shimmering phosphorescence on the sea and the spinning planets and an expanding universe, all bound together by the elastic string of time. It is advisable to look from the tide pool to the stars and then back to the tide pool again."
― John Steinbeck
REFERENCES
- In Arctic winter, marine creatures migrate by the light of the moon, ScienceDaily, 7 January 2016.
- Moonlight Drives Ocean-Scale Mass Vertical Migration of Zooplankton during the Arctic Winter, Kim S. Last, Laura Hobbs, Jørgen Berge, Andrew S. Brierley, Finlo Cottier, Cell Press, 7 January 2016.
- The Log from the Sea of Cortez, John Steinbeck, Penguin Books, 18 January 2001.
- Zooplankton, Wikipedia.