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Juvenile Jacana Bird Downies
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Eight species of jacana are known from six genera. The fossil record of this family is restricted to a recent fossil of the wattled jacana from Brazil and a Pliocene fossil of an extinct species, Jacana farrandi, from Florida. A fossil from Miocene rocks in the Czech Republic was assigned to this family, but more recent analysis disputes the placement and moves the species to the Coraciidae.
They are identifiable by their huge feet and claws which enable them to walk on floating vegetation in the shallow lakes that are their preferred habitat. They have sharp bills and rounded wings, and many species also have wattles on their foreheads.
In terms of sexual size dimorphism, female Jacanas are larger than the males. The latter, as in some other wader families like the phalaropes, take responsibility for incubation, and some species (notably the northern jacana) are polyandrous. However, adults of both sexes look identical, as with most shorebirds. They construct relatively flimsy nests on floating vegetation, and lay eggs with dark irregular lines on their shells, providing camouflage amongst water weeds.
Their diet consists of insects and other invertebrates picked from the floating vegetation or the water’s surface.
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