By far the best known and most popular of
home aquarium fish, aside from the goldfish, is the guppy or rainbow fish
(lepistes reticulates, also called the millions fish). Guppies take their
name from R. J.
Lechmere Guppy, president of the Scientific Association of
Trinidad, who presented the British Museum with specimens of the species
in the late nineteenth century. Since then many handsome exotic types have
been developed. In courtship the smaller males (one inch long) are
particularly interesting, fanning out their colorful tails to attract the
females. Guppies bear their young live, giving birth to from an average of
50 to as many as 185 babies at a time and bearing offspring every four
weeks. Abundant in South America, the fish devour mosquito larvae and so
help to prevent malaria. They have also proved useful in genetic
experiments.
The streamlined guppy submarine developed toward the end of World War II
is named for the guppy, but its name is also an acronym, the first four
letter standing for "greater underwater propulsion power." The guppy was
twice as fast as any old-style sub.