The roof rat (Rattus rattus) is a species of house rat native to Southeast Asia that lives around human dwellings. It prefers high places such as attics, is strongly arboreal, and spread worldwide via coastal areas and ships. Many individuals are dark-colored and the tail is often longer than the head and body. Omnivorous but preferring plant material, it commonly feeds on fruit and grain. It is nocturnal, forms multi-male multi-female colonies, and breeds year-round. The IUCN lists it as Least Concern.