title: Introduction. Melatonin and the light-dark zeitgeber in vertebrates, invertebrates and unicellular organisms.
authors.affiliation: Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio 78284-7762.
authors.forename: B
authors.initials: B
authors.lastname: Poeggeler
mesh_terms: D000375:Aging; D000818:Animals; D001683:Biological Clocks; D005075:Biological Evolution; D002940:Circadian Rhythm; D003624:Darkness; D008027:Light; D008550:Melatonin / Q000032:analysis / Q000502:physiology*
chemical_list: D008550:Melatonin