Social mimicry, a relatively rare evolutionary event in nature, is seen in this group. The green toucanets ( Aulacorhynchus) are represented by seven species the aracaris ( Pteroglossus) by 12 species the black toucanets ( Selenidera) by six species the saffron toucanet ( Baillonius) is monotypic and in Peters is lumped into genus Andigena the mountain toucans ( Andigena) are represented by four species and the true toucans ( Ramphastos) by 11 species. Species derived from drier biomes later became sympatric (inhabiting the same range but not interbreeding) when tropical forest expanded in Amazonia, forcing the dry forest specialists to adapt to tropical forest or perish. The rapid formation and disappearance of new Pleistocene biomes enhanced speciation rates in this region. Toucan speciation apparently occurred during Pleistocene glaciations (characterized by dry forest expansions) and interglaciations (characterized by tropical forest expansions). Haffer proposed the most widely accepted theory of speciation in toucans, and his model has since been applied to other Amazonian bird groups. The toucans' closest relatives are barbets (Capitonidae), and the two groups are thought to have evolved from a common ancestor in their landmark 1993 study, Sibley and Ahlquist describe toucans as "New World barbets with big bills." Woodpeckers (Picidae) are closely allied to the toucans, which are also similar to hornbills (Bucerotidae), albeit more distantly related. No fossilized remains of this family are known recent remains of a toco toucan ( Ramphastos toco), from the Pleistocene (20,000 years old) have been found, in Minas Gerais, Brazil. The toucans (Ramphastidae) are a very striking group. South America south to northern Argentina Evolution and systematics Predominately tropical and montane rainforest We find it Brazil, Guiana’s, Paraguay, Bolivia and northern Argentina.Medium-sized to large birds, instantly recognizable by their strikingly large and colorful bills often associate in small flocks when foraging Toco Toucan occurs in large parts of centre and eastern South America where this species is resident, only performing local movements according to the food sources. It prefers semi-open habitats, coastal forest edges, forest patches, savannahs with palm groves, plantations, wooded islands, streamsides, scrubs and orchards. Unlike the other toucans, the Toco Toucan is a non-forest species. During displays and fights, the wings produce much noise. It sings by stretching the head out and up, and swinging from side to side. It also gives rattling calls and uses its fine tongue inside the closed bill to produce clacking sounds and with the bill too. Toco Toucan utters deep, coarse, grunting “groomkk” notes in series. But there are numerous variations in both races. albogularis, has shorter bill, less yellow on the white bib and very thin red breast band. The shorter bill has irregular brownish markings and lacks the black spot on tip. Immature is duller, rather sooty-black with paler colours and whitish eye-ring.
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