Head to head
Medaka vs Zebrafish
The medaka and the zebrafish are both small, unassuming fish that became scientific superstars, each earning a landmark distinction in a different corner of biology, one in the history of spaceflight, the other in the study of regeneration and genetics.
| Medaka | Zebrafish | |
|---|---|---|
| Scientific name | Oryzias latipes | Danio rerio |
| Claim to fame | First fish bred successfully in space | Leading vertebrate model organism, regrows its heart |
| Native range | Japan and parts of East Asia | Ganges and Brahmaputra basins, South Asia |
| Traditional habitat | Rice paddies and irrigation channels | Rice paddies, ditches, and floodplain pools |
| Organ regeneration | Not a defining trait | Regrows heart tissue, fins, and retina |
| Research use | Genetics and environmental toxicology | Genetics, development, and regenerative medicine |
| Diet | Omnivore | Omnivore |
| Conservation status | Near Threatened | Least Concern |
Medaka vs Zebrafish: common questions
Which fish was the first to breed in space, the medaka or the zebrafish?
The medaka, which became the first fish to successfully breed in orbit during a Japanese space shuttle experiment, with offspring completing their life cycle in microgravity.
Which fish can regrow its own heart, the medaka or the zebrafish?
The zebrafish, which can regenerate a significant portion of its heart within weeks of injury, a remarkable regenerative ability the medaka is not particularly known for.
Are both the medaka and zebrafish important to scientific research?
Yes, both are widely used as model organisms, the medaka especially in genetics and environmental toxicology research, and the zebrafish as one of the leading vertebrate models in genetics, development, and regenerative medicine.