Animal Pictures Archive
Animal Photo Album

New Photos Animal News Animal Sounds Animal Movies Upload Photo Copyright Korean
Funny Animal Photos Monsters in Animalia Wiki Articles   Fun Facts about Animals Links Home Mobile A.P.A.
Delete Modify    
Dichromatic Toucanets (Genus: Selenidera) - Wiki latin dict size=94   common dict size=512
Image Info Original File Name: Guianan Toucanet, Selenidera culik.jpg Resolution: 576x795 File Size: 101652 Bytes Upload Time: 2007:12:10 14:13:45
Author Name (E-mail): Unknown
Subject Dichromatic Toucanets (Genus: Selenidera) - Wiki

Dichromatic Toucanets (Genus: Selenidera) - Wiki; Image ONLY
Email : E-Card | Poster | Web Master    Delete   Edit Info   Admin

Dichromatic Toucanets (Genus: Selenidera) - Wiki

From Wikipedia, the free encyclopedia

Order: Piciformes
Family: Ramphastidae
Genus: Selenidera

[Photo] Guianan Toucanets (Selenidera culik), from Monograph of the Ramphastidae by John Gould (1804-1881). Female above, male below.

Selenidera is a bird genus containing five to seven species of dichromatic toucanets in the toucan family Ramphastidae. They are found in lowland rainforest (below 1500m) in tropical South America with one species reaching Central America.

All the species have green upperparts, red undertail-coverts and a patch of bare blue or blue-green skin around the eye. Unlike most other toucans, the sexes are different in colour (sexually dichromatic; hence the name dichromatic toucanets). The males all have a black crown, nape, throat and breast and an orange/yellow auricular streak. The females of most species have the black sections in the male replaced by rich brown and a reduced/absent auricular streak, while the female of one species, the Guianan Toucanet, has grey underparts and a rufous nuchal collar, and the female of another, the Yellow-eared Toucanet, resemble the male except for its brown crown and lack of an auricular streak. The calls are low-pitched and croaking. Most species are relatively small toucans with a total length of 30-35 cm (12-14 in), but the Yellow-eared Toucanet typically has a total legnth of approx. 38 cm (15 in).

They tend to forage alone or in pairs, feeding mainly on fruit. They are fairly quiet and elusive birds which generally keep to dense cover. The nest is a cavity in a tree which the birds enlarge by excavating with their bills. The white eggs are incubated by both parents.

Species list
Guianan Toucanet, Selenidera culik
Tawny-tufted Toucanet, Selenidera nattereri
Gold-collared Toucanet, Selenidera reinwardtii
- Langsdorff's Toucanet or Green-billed Toucanet, Selenidera (reinwardtii) langsdorffii
Gould's Toucanet, Selenidera gouldii - sometimes included in S. maculirostris
Spot-billed Toucanet, Selenidera maculirostris
Yellow-eared Toucanet, Selenidera spectabilis

Speciation in Selenidera
The genus Selenidera was used by the German biologist J??rgen Haffer as an example of the "refugia" hypothesis of speciation. He suggested that the different species evolved from one common ancestor whose population was fragmented by the retreat of the rainforest into the wettest areas during periods of dry climate in the Pleistocene epoch. The single species developed into several species in these isolated refugia. When the forest expanded again during a wetter period, the ranges of the different species expanded until they came into contact with each other, forming a complementary pattern of distributions.

The refugial hypothesis is somewhat disputed as there is little field data to support or reject it. In any case it is simply one of several competing hypotheses to explain Amazonian biodiversity, each of which may or may not be provide a good explanation for the geographical pattern found in any one group of taxa. In the present case, the refugia hypothesis is probably correct, as the Amazonian Selenidera have distributions centered on major river systems; they might be considered a superspecies. Some other birds from the region, in contrast, have sister species that are separated by the major rivers, which thus apparently acted as natural barriers to gene flow. Whether a refugia or a barrier model describes superspecies distribution in the Amazonian basin most appropriately thus seems to be a direct consequence of the animals' ability to cross major waterways. But even in the Selenidera toucanets which, though largely sedentary, are technically able to disperse widely, the Amazon River forms a barrier that was simply too wide to cross in significant numbers as to inhibit speciation.
The text in this page is based on the copyrighted Wikipedia article shown in above URL. It is used under the GNU Free Documentation License. You may redistribute it, verbatim or modified, providing that you comply with the terms of the GFDL.

Copyright Info does not have the copyright for this image. This photograph or artwork is copyright by the photographer or the original artist. If you are to use this photograph, please contact the copyright owner or the poster.

Search Major Animal Websites
Need further identification?
Any comment?
Leave your message here.
Name :    PASSWORD :
Email :
Back List Upload Home Korean
CopyLeft © since 1995, Animal Pictures Archive. All rights may be reserved.