|Other names||Instant Life|
|Type||novelty aquarium pet|
|Inventor||Harold von Braunhut|
Sea-Monkeys is a brand name for brine shrimp—a group of crustaceans that undergo cryptobiosis—sold in hatching kits as novelty aquarium pets. Developed in the United States in 1957 by Harold von Braunhut, the product was heavily marketed, especially in comic books, and remains a presence in popular culture. May 16 is National Sea-Monkey Day in the United States.
Ant farms had been popularised in 1956 by Milton Levine. Harold von Braunhut invented a brine-shrimp-based product the next year, 1957. Von Braunhut collaborated with marine biologist Dr. Anthony D’Agostino to develop the proper mix of nutrients and chemicals in dry form that could be added to plain tap water to create a purified habitat for the shrimp to thrive. Von Braunhut was granted a patent for this process on July 4, 1972.
They were initially called "Instant Life" and sold for $0.49, but von Braunhut changed the name to "Sea-Monkeys" in 1962. The new name was based on the supposed resemblance of the animals' tails to those of monkeys, and their salt-water habitat.
Sea-Monkeys were intensely marketed in comic books throughout the 1960s and early 1970s  using illustrations by the comic-book illustrator Joe Orlando. These showed humanoid animals that bear no resemblance to the crustaceans. Manyas stating: "I think I bought something like 3.2 million pages of comic book advertising a year. It worked beautifully."
A colony is started by adding the contents of a packet labelled "Water Purifier" to a tank of water. This packet contains salt, water conditioner, and some brine shrimp eggs. After 24 hours, this is augmented with the contents of a packet labelled "Instant Life Eggs", containing more eggs, yeast, borax, soda, salt, some food and sometimes a dye. The Sea-Monkeys that hatched from the original eggs seem to appear instantly. "Growth Food" containing yeast and spirulina is then added every few days.
The animals sold as Sea-Monkeys are an artificial breed known as Artemia NYOS (New York Ocean Science), formed by hybridising different species of Artemia. They undergo cryptobiosis or anhydrobiosis, a condition of apparent lifelessness which allows them to survive the desiccation of the temporary pools in which they live.
Astronaut John Glenn took Sea-Monkeys into space on October 29, 1998 aboard Space Shuttle Discovery during mission STS-95. After nine days in space, they were returned to Earth, and hatched eight weeks later apparently unaffected by their travels. However, earlier experiments on Apollo 16 and Apollo 17, where the cysts travelled to the Moon and back and were exposed to significant cosmic rays, observed a high sensitivity to cosmic radiation on Artemia salina eggs; only 10% of the embryos which were induced to develop from hit eggs survived to adulthood.
- The Amazing Live Sea Monkeys
- "Simpsons Already Did It", a South Park episode that prominently features a parody of Sea Monkeys called Sea People.
- Hitt, Jack (April 15, 2016). "The Battle Over the Sea-Monkey Fortune". The New York Times. Retrieved April 16, 2016.
- Coopee, Todd. "Sea-Monkeys". ToyTales.ca.
- May Berenbaum (2000). "Sea monkey see, sea monkey do". Buzzwords: a Scientist Muses on Sex, Bugs, and Rock 'n' Roll. Joseph Henry Press. pp. 45–49. ISBN 978-0-309-06835-2.
- Tim Walsh (2005). "Ant Farm and Sea-Monkeys". Timeless Toys: Classic Toys and the Playmakers who Created Them. Andrews McMeel Publishing. pp. 124–129. ISBN 978-0-7407-5571-2.
- Sharon M. Scott (2010). "Sea-Monkeys". Toys and American Culture: an Encyclopedia. ABC-CLIO. pp. 282–284. ISBN 978-0-313-34798-6.
- H. Bücker & G. Horneck (1975). "The biological effectiveness of HZE-particles of cosmic radiation studied in the Apollo 16 and 17 Biostack experiments". Acta Astronautica. 2 (3–4): 247–264. doi:10.1016/0094-5765(75)90095-8.