SummaryFrith, C. B.&Frith, D. W. (1990). Nesting biology and relationships of the Lesser MelampittaMelampitta lugubris. Emu90, 65–73.Four active nests of the Lesser MelampittaMelampitta lugubriswere studied in mixed lower montane forest at Tari Gap, Southern Highlands, Papua New Guinea. Nests, eggs, sexual dimorphism and parental care of this species are described for the first time. Iris colour is red in males, dark brown in females. Only females incubate and brood young but both sexes feed the nestling, male participation increasing with nestling age. The male regularly feeds the female close to and on the nest. Incubation period is at least 27–28 days and nestling period 35 days in one nest and at least 31 and 32 days in two others. DNA-DNA hybridisation studies suggest this species is a bird of paradise of the subfamily Paradisaeinae closest toManucodia.Lesser Melampitta biology indicates, however, that it is unlike paradisaeine birds of paradise in most respects but is more like cnemophilineCnemophilus macgregoriito which it would seem closest if its placement within Paradisaeidae is correct.