Evolution and systematics

With their brilliant colors and energetic ways, jacamars resemble hummingbirds but are actually related to puffbirds, toucans, and woodpeckers. Like all members of the order Piciformes, jacamars and their relatives have zygodactyl feet, with two toes pointing forward and two facing back. Jacamars evolved with this toe arrangement, which helps them grasp branches while hunting in trees. Jacamars, like woodpeckers and other piciform birds, are cavity nesters: they tunnel into the ground to build nests. Scientists believe jacamars are closely related to Old World bee-eaters, which also prey on flying insects, have similar plumage, and raise their young in the same manner.

Jacamars tend to live near lush tropical rainforests, which have a dazzling variety of large, colorful butterfly species. Ja-camars have become highly selective predators. They often make their homes near streams, drilling nest cavities into steep banks and upturned tree roots.

Because 13 of the 17 Galbulidae species belong to super-species complexes, researcher J. Haffer concludes that jaca-mars had a relatively recent Pleistocene radiation of the family. Jacamars are believed to have originated in the Ama zon region where they are most common, and spread to other parts of Central and South America. Unique anatomical features of this family include a long appendix, no gall bladder, a bare preen gland, and a long, thin tongue.

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