Wikipeda : The Siamese fighting fish (Betta splendens), also known as the betta, is a freshwater fish native to Thailand (formerly Siam) and present in neighboring Cambodia, Laos, Malaysia, and Vietnam. While colloquially known and marketed in the global aquarium trade as the "betta", it is one of 73 species in the genus Betta.
Siamese fighting fish are among the most popular and widely available aquarium fish in the world, due to their varied and vibrant colour, diverse morphology, and relatively low maintenance
Mostly concentrated in Thailand's Chao Phraya river basin, bettas were discovered in the still waters of canals, rice paddies and floodplains, where they are still found; they have been kept and bred since at least the mid-19th century, and possibly much earlier.[4] Their famously vibrant colours, large and flowy fins, and aggressive behaviour are the result of generations of intensive artificial selection, for which they are sometimes known as "designer fish of the aquatic world".
Bettas are well known for being highly territorial, with males prone to attacking each other if housed in the same tank; without a means of escape, this will usually result in the death of one or both fish. Female bettas can also become territorial towards one other in too small of an aquarium. Bettas are exceptionally tolerant of low oxygen levels and poor water quality, owing to their special labyrinth organ, a characteristic unique to the suborder Anabantoidei that allows for the intake of air.
