Physical characteristics

Weaverfinches are relatively quite small in size ranging from the 3.5 in (9 cm) quailfinches (Ortygospiza spp.) to the 6.7 in (17 cm) Java sparrow (Padda oryzivora). There are about 29 genera with about 129 species. Particularly characteristic of the weaverfinches are the projections or swellings of thickened connective tissue known as tubercles or papillae shown by the young at the edges of the bill and at the gape. These are a striking white, blue, or yellow color, often emphasized by black surroundings. In the Gouldian finch (Chloebia goul-diae) and the parrotfinches (Erythrura spp.) the tubercles have developed into organs which seem to reflect light and thus show up in the semi-darkness of the nest. A characteristic of the weaverfinches that varies according to the genus and species is the gape pattern of the nestlings. These patterns consist of dark spots or lines on the palate, the tongue, and the floor of the mouth. In contrast to the colored bulges at the angles of the gape, the patterns in the interior of the mouth are, in many cases, retained for life.

The plumage is sometimes inconspicuous, but often very attractively colored. It is never, as in many weavers, striped in a sparrow or bunting-like fashion. Adult plumage is attained over a period of six to eight weeks without a distinguishable intermediate phase as in the fringillid finches. As in the whydahs, the outermost primary is generally very much shortened. Using the physical characteristics of an individual's plumage, one can usually place it in one of the many Estrildidae groups. For example, the parrotfinches usually display combinations of vibrant greens, blues, and reds in contrast to the munias and mannikins (Lonchura spp.), which are usually characterized by various shades of browns and tans. For some of the groups, the name is descriptive and indicates that group's distinguishing feature, such as in the olive-backs (Nesocharis spp.), the crimson-wings (Cryptospiza spp.), and the bluebills (Spermophaga spp.). Sometimes, however, a group's name can be misleading, such as with the firefinches (Lagonos-ticta spp.) whose plumage usually contains colors ranging from pink to crimson red, but never what most would consider a "fiery" red. The patterning of the plumage can also help place estrildids into groups. The twinspots have white spots on their underparts and sides with each feather containing two spots, the characteristic for which they are named. The pytilias (Pytilia spp.), on the other hand, have barring in these areas in addition to a bright red face in the males. The firetails (Emblema spp.) can have either barring or spots on their sides and underparts, but their distinguishing characteristic is their bright red rump and tail.

Nestlings of species found within the family Estrildidae exhibit a combination of mouth, tongue, and palate patterns that help identify them as a particular species. Species of whydahs and indigobirds (Vidua spp.), brood parasites, have evolved to exhibit mouth patterns similar to their corresponding estrildid host species, thereby increasing the chances that the host parents will accept their new "adopted" chicks. 1. Red-billed fire-finch (Lagonosticta senegala); 2. Gouldian finch (Chloebia gouldiae); 3. White-headed munia (Lonchura maja); 4. African silverbill (Lonchura cantans). (Illustration by Joseph E. Trumpey)

Lonchura Cantans White

Nestlings of species found within the family Estrildidae exhibit a combination of mouth, tongue, and palate patterns that help identify them as a particular species. Species of whydahs and indigobirds (Vidua spp.), brood parasites, have evolved to exhibit mouth patterns similar to their corresponding estrildid host species, thereby increasing the chances that the host parents will accept their new "adopted" chicks. 1. Red-billed fire-finch (Lagonosticta senegala); 2. Gouldian finch (Chloebia gouldiae); 3. White-headed munia (Lonchura maja); 4. African silverbill (Lonchura cantans). (Illustration by Joseph E. Trumpey)

The bill of the almost exclusively insectivorous species, such as the negro-finches (Nigrita spp.) and the flowerpecker weaver-finches (Parmoptila spp.), is as slim as that of warblers. In species that eat large seeds, like the bluebills and the seed-crackers (Pyrenestes spp.), it is almost as thick and strong as that of hawfinches. The waxbills (Estrilda spp.) fall somewhere in the middle of this size range with their often bright red "waxy" bills. Tail size is also quite variable, ranging from the long central tail feathers of the grassfinches (Poephila spp.) to the unusually short tail of the quailfinches.

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