Asian mainland during Pleistocene glacial periods with low sea levels. In any case, the phylogeny and biogeography of the basal peacock-pheasants agrees with the idea of reproductive isolation due to rising sea levels during the last ice age's interglacials, whereas the more advanced Polyplectron species are limited to today's mainland Southeast Asia. Ecology A shy and elusive bird, the Malay peacock-pheasant is endemic to lowland forests of the Malay Peninsula from the Isthmus of Kra region southwards. At one time, this species was widespread in Malaysia and Thailand, and reported from southern Myanmar, Sumatra and Singapore, but it probably never occurred in the former two at least in historic times. It has since disappeared from most of its former range, with the remaining population being confined to the lowlands of central Malaysia, perhaps extending barely into Thailand. Although nothing certain is known, there is nothing to suggest that this species is anything other than a sedentary bird; individuals probably do not move a long distance from their place of hatching. They are somewhat territorial, but the ranges of several birds probably overlap except for the core areas. Males move about in an area of approximately 10–60 hectares, while the ranges of females are half that size. The average population density in suitable habitat is estimated as slightly less than seven adult birds per square kilometer. It inhabits mainly dipterocarp rainforest up to 150 m ASL, rarely occurring even as low as 300 m ASL. While it can utilize secondary forest, such habitat does not seem to be optimal. Its feeding habits are little-studied, but it probably eats a mix of plant matter (particularly fruits) and small arthropods as do its better-known relatives. It forages in typical galliform fashion, utilising its feet and bill to uncover invertebrates from forest litter. Recorded food items include insects such as Diptera, Orthoptera and Hymenoptera (e.g. carpenter ants), mollusks, isopods Camponotus, and fruits and seeds of Annonaceae, Fabaceae and Fagaceae (e.g. stone oaks, Lithocarpus). Other items found in Malay peacock-pheasant stomachs were probably not ingested deliberately; they include moss, twigs, rootlets and part of an Apocynaceae flower. Reproduction While captive Malay peacock-pheasants may sometimes appear to polygynous or promiscuous, not forming lasting pair bonds, this is probably atypical as peacock-pheasants are as a rule monogamous with males participating in nest defense and chick rearing. The mating season is not well resolved; recently used nests have