[[Evolution]]ært har melatonin en 700 millioners års historie bag sig, idet det har vist sig at [[gen]]er for biosyntesen af melatonin ud over dyr ( både [[vertebrat]]er og [[invertebrat]]er) deles af planter og mikrober.<ref>[http://www.nytimes.com/2014/10/02/science/the-evolution-of-sleep-700-million-years-of-melatonin.html The Evolution of Sleep: 700 Million Years of Melatonin. The New York Times. Science]</ref><ref name="Caniato2003">{{cite journal | author = Caniato R, Filippini R, Piovan A, Puricelli L, Borsarini A, Cappelletti EM | title = Melatonin in plants | journal = Adv. Exp. Med. Biol. | volume = 527 | issue =  | pages = 593–7 | year = 2003 | pmid = 15206778 | doi = 10.1007/978-1-4615-0135-0_68 | url =  | isbn = 978-0-306-47755-3 | series = Advances in Experimental Medicine and Biology }}</ref><ref name="Paredes2009">{{cite journal | author = Paredes SD, Korkmaz A, Manchester LC, Tan DX, Reiter RJ | title = Phytomelatonin: a review | url = https://archive.org/details/sim_journal-of-experimental-botany_2009_60_1/page/57 | journal = J. Exp. Bot. | volume = 60 | issue = 1 | pages = 57–69 | year = 2009 | pmid = 19033551 | doi = 10.1093/jxb/ern284 }}</ref>
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