Trogoniformes are an order comprising 40 bird species common to warm regions. Trogons occur in the New World from the extreme southwestern United States and the West Indies to Argentina; throughout sub-Saharan Africa; and from India to Malaya and the Philippines. The fossil record of the trogons dates back 49 million years to the mid-Eocene.

Trogons are the only bird with a heterodactyl toe arrangement, with digits 3 and 4 pointing forward and digits 1 and 2 pointing back. Their legs and feet are weak and short. The ratio of leg muscle to body weight is only 3%, the lowest of any bird. Their skin is very thin, making preparation of study skins very difficult.

Trogons feed primarily on insects, notably caterpillars, of which they are, with cuckoos, among the most frequent predators. They catch insects like flycatchers do, watch from their perch, then dart out, grab the insect and return to their perch. Violaceous Trogons eat wasps and their larvae while digging their nests.

When breeding, females Quetzals lay two pale blue eggs in a nest placed in a hole which they carve in a rotten tree. The availability of suitable trees in the required state of decomposition may limit the Quetzal population. Both parents take turns at incubating, with their long tail-covert feathers folded forwards over the back and out of the hole. The incubation period lasts about 18 days. Both parents take care of the young, but the mortality rate of the chicks is very high, about 80 percent, with many of them dying without ever leaving the nest.

http://en.wikipedia.org/wiki/Trogon

Hackett SJ et al (2008): Phylogenomic Study of Birds

"Quetzalcóatl." Encyclopædia Britannica Ultimate Reference Suite.  Chicago: Encyclopædia Britannica, 2011.

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