Small World, Smaller Creatures2

Loligo pealei (squid embryos), 5 days (80x),

Courtesy Nikon Small World Photo Micrography Competition: Photographed by Dr. Rachel Fink

These adorable little creatures look like a trio of dapper dandies stuffed into acorns, but they’re actually mini-squids. The gestation period of squid eggs varies according to the temperature of the water in which they were laid (in warm climes, they can hatch in around 11 days; in colder waters, it can take up to 27). The embryos here are still young, but they’re already differentiated enough to have eyestalks and mouths, and you can just make out the budding tentacles.

Embryonated eggs of Oryzias latipes (Japanese rice fish) in Java moss (12x)

Courtesy Nikon Small World Photo Micrography Competition; Photographed by Alex Griman

Here’s a fun fact about the Japanese rice fish: it was the first vertebrate to mate in outer space. On a 1994 mission of the Space Shuttle Columbia, four carefully selected rice fish, including a lusty young “playboy,” were placed in a sealed aquarium and left alone to do their thing (click here for a play-by-play). After some missteps—the playboy apparently struggled to keep his balance in zero-g and mistakenly executed “a circle dance of courtship” around another male—the proper rice fish finally managed to connect. A few days later, a fry of baby fish was hatched from fertilized eggs much like the ones pictured above.

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