f all the groups of birds in the world, few fit our ideas of “tropical forest birds” as well as the trogons and quetzals. They are found almost entirely between the Tropics of Cancer and Capricorn, from northern Mexico to northern Argentina. Furthermore, nearly all of them depend on hollows in large trees for nest sites, except for a few species that excavate cavities in the paper-mache-like homes of tree-dwelling termites or arboreal wasp nests.Beyond that, trogons and quetzals conform to our ideas of how exotic tropical birds should appear. Nearly all of the approximately 40 species are colored iridescent forest green to bluish violet above and brilliant red, orange, or yellow below—colors as intense as those of the brightest orioles or tanagers. Yet these brilliant hues so effectively hide the birds from the human eye amid their surrounding forest vegetation that they are like one of those picture puzzles designed to test a person’s visual abilities, in which you must discern a familiar shape in a confusing maze of intersecting lines and colors. The birds often remain maddeningly motionless, occasionally uttering monotonous repeated notes or, if you are very lucky, briefly spreading or defiantly flicking their tails up and down, as if certain that no mere human could possibly see them.
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