Cameroon Indigobird
Vidua camerunensis
A nest parasite that lays its eggs in the nests of African and Black-bellied Firefinches and Brown and Dybowski's Twinspots. Breeding males are glossy black with blue iridescence and a pale brownish panel in the wings. Females and non-breeding males are streaky and brown on the back and pale below, with a bold facial pattern. The bill is whitish and the legs very pale purplish. Found locally in lush woodland, savanna, and cultivated areas. Given current knowledge, can only be confidently identified by mimicked vocalizations. Each male parasitizes only one of the four host species and imitates its vocalizations, often mixing them into a scratchy jumble of high-pitched notes.
分类信息
- 学名
- Vidua camerunensis
- 命名信息
- (Grote, 1922)
- 目
- Passeriformes
- 科
- Viduidae
- 属
- Vidua
分布与栖息地
- 迁徙
- Resident species
行为
Cameroon indigobirds are known for song determination and mimicking the songs of other bird species. The males pick which songs to mimic; however, when one male chooses a song from a host bird, the other males mimic other songs from a different host species. This is an effective way to differentiate males when mimicking the songs. There are several distinct host species that the indigobirds mimic from; the most common are the black-bellied firefinch (Lagonosticta rara) and African firefinch (L. rubricata).<p>The variation in how indigobirds mimic different songs is based on the host species. Researchers have thought that because different indigobird species sing different songs, they must be reproductively isolated. However, when a paternity test was done between the different species, it was found that the birds were not reproductively isolated. They concluded that indigobirds switch songs among several different hosts, but that this switching does not mean that the species are biologically different. In fact, they are very much related to one another in which they are not isolated from other species. Reproductive isolation cannot be determined just by the shifts of song mimicry from different hosts.<p>The indigobirds also use song mimicry for sexual and natural selection. Male indigobirds are most territorial and aggressive when they hear their own song or the host song that they mimic. These birds know and recognize which song is the one they mimic, compared to what other species mimic. For natural selection, it is in the bird's favor to mimic another song compared to other species. They save resources because they do not have to fight with others to mark their territory, thus decreasing their aggressiveness. As for sexual selection, females are attracted to males that master the art of mimicry. A female decides to mate with the male who sings the song that is most known to the females. The eggs are laid in another host's nest instead of their own.<p>Song discrimination is also very important in the young. They learn to sing and mimic songs in their sensitive period. It is very important in establishing their mimicry for the best fit in natural selection and reproduction with sexual selection.
保护状况
- 种群趋势
- stable
照片
分布
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