As they do in the wild, the young male indigobirds picked up the songs of their foster parents.
Indigobirds that grew up in a novel nest could accept the songs of their new foster parents and prefer mates with the same oddball background.
A small genetic analysis 5 years ago found some support for the idea that indigobirds diverged from other birds much more recently than their hosts did, a finding that favors the song scenario over cospeciation of indigobirds and hosts.
Differences in gene frequencies made it clear that the species of indigobirds are distinct, even though the entire group is unusually similar genetically, Sorenson says.
In the field, occasional males (1% of 484 males, in areas where two or more species of indigobirds live together) have songs mimicking a species of estrildid that is not the normal host of this species of indigobird (Payne et al.
Genetic distances between species of Vidua other than those within the paradise whydah and indigobird species complexes are comparable to distances between the estrildid finch species (2-4%).
Song mimicry by the village indigobird (Vidua chalybeata) of the red-billed firefinch (Lagonosticta senegala).
A new species of firefinch Lagonosticta from northern Nigeria, and its association with the Jos Plateau indigobird Vidua maryae.
The models were tested in two species groups of Vidua finches, the indigobirds and the paradise whydahs, and in their host species.
Brood parasite/song mimic Host Indigobirds Firefinches and twinspots Vidua chalybeata Lagonosticta senegala V.
Cleavage sites for each taxon were independently mapped (Appendix 2) (but with only two independent maps representing indigobirds due to the high genetic similarity among all indigobirds) using double and triple digests (Brown and Vinograd 1974; Dowling et al.
Haplotypes defined as unique associations of restriction sites were the units of analysis (taxa) except that an additional analysis of relationships within Vidua was done treating individual indigobirds as taxa.
- To test the relationships within the species complexes of the indigobirds and the paradise whydahs, and whether these two species groups each were monophyletic, we estimated the phylogenetic relationships among all Vidua.
The following estrildid finches were included as outgroups for rooting the phylogenetic tree: (1) cut-throat finch, Amadina fasciata, a species that in another molecular genetics study (Kakizawa and Watada 1985) was determined to represent the basal split of the set of African estrildid finches that includes all host species of the viduas; (2) orange-winged pytilia, Pytilia afra, a host of the paradise whydahs; (3) redbilled firefinch, Lagonosticta senegala, a host of the indigobirds; and (4) green twinspot, Mandingoa nitidula, which is not known to be a host.
For the indigobirds and their hosts the comparisons were made only within the same geographic region of Africa.