Pethia tiantian Pethia tiantian Pethia tiantian is a species of cyprinid fish that has only been recorded from streams in the vicinity of Putao in the far north of Myanmar. It grows to a length of SL. It is generally brownish with a dark vertical bar just behind the operculum and a round dark blotch on the caudal peduncle. Other "Pethia" species are similarly marked but "P. tiantian" can be distinguished by its longer lateral line, reaching all the way back to the base of the caudal fin. "P. didi", a similarly marked species found in the same drainage basin, differs from
History of model organisms respective work on natural selection and the genetics of heredity. These early works in finding standards to compare organisms against continued into the 20th century as the first model organisms were brought into laboratories. Beginning in the early 1900s "Drosophila" entered the research laboratories and opened up the doors for other model organisms like Tobacco mosaic virus, E. coli, C57BL/6 (lab mice), etc. These organisms have led to many advances in the past century. Some of the first work with what would be considered model organisms started because Gregor Johann Mendel felt that the views of Darwin were insufficient in