Zebrafish their larval stages. In 2011, the British Heart Foundation ran an advertising campaign publicising its intention to study the applicability of this ability to humans, stating that it aimed to raise £50 million in research funding. Zebrafish have also been found to regenerate photoreceptor cells and retinal neurons following injury, which has been shown to be mediated by the dedifferentiation and proliferation of Müller glia. Researchers frequently amputate the dorsal and ventral tail fins and analyze their regrowth to test for mutations. It has been found that histone demethylation occurs at the site of the amputation, switching the zebrafish's cells
Tropical fish knowledge on how to maintain marine fish as well as the increasing number of aquarium-bred species is seeing a gradual rise in their popularity. Many marine tropical fish, particularly those of interest to fishkeepers, are those that live among or in close relation to coral reefs. Coral reefs form complex ecosystems with tremendous biodiversity. Among ocean inhabitants, tropical fish stand out as particularly colorful. Hundreds of species can exist in a small area of a healthy reef, many of them hidden or well camouflaged. Reef fish have developed many ingenious specialisations adapted to survival on the reefs. Some recreational SCUBA