Zebra Danio

🌍 Overview

The zebra danio is a small, fast-swimming schooling fish native to the shallow streams, ditches, and monsoon-flooded rice paddies of South Asia. Unlike livebearing guppies and mollies, danios are egg-scatterers: a spawning pair releases eggs into open water or fine-leaved plants, with no nest built and no parental care afterward. Outside the aquarium hobby, the zebra danio is best known as zebrafish, the most widely used non-mammalian vertebrate model organism in developmental biology and genetics research. Its embryos develop transparently outside the mother's body, and roughly 70 percent of human genes have a working counterpart in its genome, a combination that has made it a mainstay of labs studying development, disease, and drug discovery since the 1990s.

📋 Quick Facts

📜 History

Francis Hamilton, a Scottish physician working under the East India Company, described the fish in 1822 from specimens collected in Bihar, calling it a beautiful fish with blue and silver stripes along each side. Its second life began at the University of Oregon, where George Streisinger spent the 1970s adapting a pet shop fish to genetics work. In 1981 he published a paper in Nature reporting the first large-scale production of genetically uniform clones of a vertebrate. Early laboratory strains were founded with animals bought from the pet trade or collected in the wild, and Streisinger's methods went on to spread to more than 500 labs in 32 countries.

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🤩 Fun Facts