The tinamous are one of the most ancient groups of bird, members of a South American bird family of about 47 species in 9 genera. Although they look similar to other ground-dwelling birds like quail and grouse, they have no close relatives and are classified as a single family Tinamidae within their own order, the Tinamiformes.
Of Gondwanan origin, they are distantly related to the ratites (order Struthioniformes), that includes the rheas, emu, and kiwi. Although the fossil record in South America is generally poor, the known tinamou fossil record goes back 10 million years.
Together with the ratites, they make up the Paleognathae, or “Old Jaws”, as distinct from the vast majority of modern birds in the Neognathae, or “New Jaws”.
There are 47 species of tinamou in South America and north to Mexico, occurring in a wide range of habitats. They eat a variety of food including insects and berries. The smallest species, the Dwarf Nothura, is about 42 grams (1.4 oz) and 15 cm (6 inches) long. The largest tinamou, the Gray Tinamou, weighs 1.6 kg (3.6 lbs) and measures up to 50 cm (20 inches) long.
Tinamou are rarely seen. Most inhabit the tropical lowlands of South America, typically in dark, dense forest, but some species range as far north as Mexico and occur in a wide range of habitats.
Although some species are quite common, they are shy and secretive. A small number of species live in more open, grassy country, but even these are wary. Tinamous lay several eggs which are attractively coloured and have a hard gloss like porcelain. The young are precocial, and can run almost as soon as they hatch.