Piciformes

Piciformes are an order of birds containing about 67 living genera with a little over 400 species, of which the Picidae (woodpeckers and relatives) make up about half. Amost all live in woods (arboreal).
In general, the Piciformes are insectivorous, though the barbets and toucans mostly eat fruit and the honeyguides are unique among birds in digesting beeswax (though insects make up most of their diet).
Nearly all Piciformes have parrot-like zygodactyl feet—two toes forward and two back, an arrangement that has obvious advantages for birds that spend much of their time on tree trunks. An exception are a few species of three-toed woodpeckers. The jacamars aside, Piciformes do not have down feathers at any age, only true feathers. They range in size from the rufous piculet at 8 centimetres in length, and weighing 7 grams, to the toco toucan, at 63 centimetres long, and weighing 680 grams. All nest in cavities (holes) and have altricial young, meaning they have to look after their chicks for quite a long time.
Classification.
Order: PICIFORMES