DMT was first synthesized in 1931 by chemist Richard Helmuth Fredrick Manske (born 1901 in Berlin, Germany – 1977). In general, its discovery as a natural product is credited to Brazilian chemist and microbiologist Oswaldo Gonçalves de Lima (1908–1989) who, in 1946, isolated an alkaloid he named "nigerina" (nigerine) from the root bark of "jurema preta", that is, "Mimosa tenuiflora". However, in a careful review of the case Jonathan Ott shows that the empirical formula for nigerine determined by Gonçalves de Lima, which notably contains an atom of oxygen, can match only a partial, "impure" or "contaminated" form of DMT. It was only in 1959, when Gonçalves de Lima provided American chemists a sample of "Mimosa tenuiflora" roots, that DMT was unequivocally identified in this plant material. Less ambiguous is the case of isolation and formal identification of DMT in 1955 in seeds and pods of "Anadenanthera peregrina" by a team of American chemists led by Evan Horning (1916–1993). Since 1955, DMT has been found in a host of organisms: in at least fifty plant species belonging to ten families, and in at least four animal species, including one gorgonian and three mammalian species (including humans).