Bearded Dragons have broad triangular heads and flattened bodies, with adults reaching approximately 24 inches head-to-tail. When threatened or aroused, they will expand a spiny pouch under their jaw to make them appear larger. This pouch, especially in its expanded state, resembles a beard, lending the animal their name, this pouch will also turn black, also contributing to the "bearded look". Males are often slightly larger than females, with a larger head in proportion to their bodies, but females are often slightly more heavily set. Males also typically have darker "beards," and have two bulges just posterior to the cloaca, where only a single, medially-located lump is present in a female. Bearded Dragons have a distinctive series of lateral spines (specialized scales) radiating horizontally from the head to the base of the tail. Their colour ranges from light tan to dark brown or green, depending on their native soil, often with highlights of black, or brilliant red or gold, and can change somewhat depending upon their internal condition. Some captive populations have been selectively bred for more brilliant red and gold colorations. As juveniles, they are semi-arboreal. As adults, they are mostly terrestrial, but will climb to bask and search for prey. Bearded Dragons occupy a large range of habitats from the desert to dry forests and scrublands.