Laura L. Payne

BIOLOGICAL AND CULTURAL SUCCESS OF SONG MEMES IN INDIGO BUNTINGS

Song behavior, breeding success, and survival of individuals and the survival of their local song traditions or memes were compared in two populations of Indigo Buntings (Passerina cyanea) in southern Michigan. First-year males were less successful than older males. First-year males with the song of a neighboring adult tended to be more successful in mating and in fledging young than were 1st-yr males that retained an individualistic song. Adults that were members of a local song neighborhood tended to be more successful than adults that were not. Reproductive and survival success of individual birds did not vary with the number of males in the meme. The different song traditions (memes) are equivalent in biological terms to mating success, breeding success, and survival of their bearers. Memes are successful in a cultural sense if they survive from year to year. Meme survival is determined largely by the number of individual birds in the song group; chances are high that at least one male with the song will return in the larger groups. Songs are learned outside the family context, kin usually do not have the same song, and a female selects a mate independently of whether his song is the same as her fathers. The change over time in the local meme pool is independent of any obviously associated genetic traits, and cultural extinction of song memes is described in probabilistic terms of meme size.

Parental care in estrildid finches: experimental tests of a model of Vidua brood parasitism

To assess the potential success of a brood parasite with a novel host, we tested whether three species of African estrildid finches provide foster parental care only to young with normal conspecific appearance and behaviour or also to other young in their nests. One (red-billed firefinch, Lagonosticta senegala) has a mimetic brood parasite in the field, one (goldbreast, Amandava subflava) has a nonmimetic brood parasite and one (blue-capped cordon-bleu, Uraeginthus cyanocephalus) has no brood parasite. All three species sometimes reared nestlings of other species to fledging, and all three reared the brood parasite of the firefinch, the village indigobird, Vidua chalybeata. Finches were more successful in rearing young of their own than young of other species, however, firefinches were as likely to rear young indigobirds as to rear their own young. Nestling mimicry gives young Vidua brood parasites a survival advantage in receiving care from firefinch foster parents. Firefinches were more likely to rear their own young in a mixed-species brood if the other species matched the appearance of their own young. There was no difference in reproductive success between novice and experienced pairs of finches rearing a brood of their own or the other species. Because these nesting species reared alien young, which were vicariant experimental stand-ins of young brood parasites, and these nesting species also reared the young indigobird, we conclude that the nestling appearance and behaviour does not completely prevent the colonization of a new host species by a brood parasite. The experimental results are consistent with molecular genetic estimates of colonization histories of estrildid hosts by Vidua brood parasites.

Splendid wren Malurus splendens response to cuckoos: an experimental test of social organization in a communal bird

A population of cooperatively breeding, group-living splendid wrens was tested with a mounted parasitic cuckoo. At all nests with incubated eggs or nestlings, wrens attacked the cuckoo. The timing and intensity of attacks was independent of the nest day and of the age and breeding experience of the wrens. The breeding female usually spotted and attacked the cuckoo first. Her mate and the nonbreeding helpers responded to her call and mobbed and attacked the cuckoo. Response was no quicker in groups with nonbreeding auxiliaries than in single pairs. Discovery time was independent of the number of birds in a group and depended on the movements of the breeding female. Most wrens fed the young and mobbed the cuckoo. When a wren did not attack, it usually was caring for the young of another breeding female or an earlier brood. Variance in helping behavior was not closely associated with variance in the genetic relationship between helper and the breeding female or the young beneficiaries of mobbing. Use of a common territory, attendance at a nest, feeding the young, and mobbing and hitting a cuckoo were all associated cooperative activities. The main limitation of cooperative behavior in defense against the cuckoo is the same as the observed constraint on care of the young during the prolonged period of parental feeding-a conflict of interest among breeding females for care of their own young.

Kin and social relationships in splendid fairy-wrens: recognition by song in a cooperative bird

Abstract Cooperatively breeding splendid fairy-wren,s Malurus splendens, were tested with songs recorded from individuals of known social and kin relationships. Both males and females sang and responded aggressively to songs of wrens from other social groups. Wrens responded similarly to songs of non-kin and songs of close kin in the absence of social familiarity with them. Breeding females responded more intensely to songs of helpers from other groups than to songs of helpers in their own group. The songs of male and female helpers elicited similar responses by breeding females. The response to other females may be associated with competition for breeding status and helpers. Two females sometimes breed in social groups with two older females; no interference was observed. Song may allow individuals to recognize other wrens in their group and to direct their behaviour towards non-dispersing relatives by location and social familiarity rather than by kinship identifiers.

Heritability estimates and behaviour observations: extra-pair matings in indigo buntings

Abstract About 2% of 156 behaviourally complete copulations observed in indigo buntings, Passerina cyanea, were extra-pair matings between a female and a male other than her mate. Morphometric similarities between parents and offspring indicated a significant heritability of body size (wing length, h2± se =0·44±0·13 for offspring and mid-parent values). Females were more similar to their offspring than were their mates. The incidence of effective extra-pair matings was estimated from the difference of offspring-father and offspring-mother regressions. The morphometric data suggest a much higher incidence of extra-pair fertilizations (40%, with wide error bounds) than did the field observations: males are not always closely related to the offspring produced on their territory. Full siblings were significantly more similar than half-siblings when the half-siblings shared a father, and not when the half-siblings shared a mother. Maternal half-siblings were more similar than paternal half-siblings, and siblings from the same nest were more similar than siblings from different nests, though not significantly so. Differences in season of birth, natal microhabitat (nest plant) and natal brood size did not affect the adult size of the buntings; no environmental traits were discovered that might explain the results as a non-genetic maternal effect. The approximately tenfold difference in the incidence of observed extra-pair copulations and of extra-pair fertilizations estimated by quantitative genetic methods is similar to the difference reported in other observational and protein electrophoretic studies in the same population.

SONG MIMICRY AND SPECIES STATUS OF THE GREEN WIDOWFINCH VIDUA CODRINGTONI

Summary Payne, R. B., Payne, L. L. & Nhlane, M. E. D. 1992. Song mimicry and species status of the Green Widowfinch Vidua codringtoni. Ostrich 63:86-97. The Green Widowfinch Vidua codringtoni mimics the songs of the Redthroated Twinspot Hypargos niveoguttatus, its apparent foster species, in Zimbabwe, Zambia and Malaŵi. Of 38 male Green Widowfinches, 37 mimicked the twinspot; one mimicked a firefinch and not the twinspot. A wild-captured juvenile developed mimicry of twinspot song after six months and retained its mimicry through the next year. Male Green Widowfinches have glossy breeding plumage (green to blue), black wings, white bill and bright orange feet, a colour combination unlike other widowfinches in their range in southern Africa. Females are marginally distinguishable from other widowfinch species. Green Widowfinches occur together locally with Black V. funerea nigerrima, Purple V. purpurascens and Steelblue V. chalybeata Widowfinches and do not interbreed with them. The four species of widowfi...

Begging for Parental Care from Another Species: Specialization and Generalization in Brood-Parasitic Finches

African indigobirds (Vidua species) are species-specific brood parasites of estrildid finches. Although the mouth patterns of nestlings mimic their host nestlings, the begging calls of young indigobirds are not host-specific, and in only some species do they resemble begging calls of the host. Adult male indigobirds mimic calls and songs of their host species. Their song incorporates two kinds of begging call, an innate call like that used by nestling indigobirds, and a second learned one when males imprint and then mimic the foster species’ begging calls in male song. We recorded young and adult indigobirds in the field, and the begging calls of young and adult song mimics reared under alternative foster species. The innate begging calls in all indigobird species matched the begging calls of only certain firefinch(Lagonosticta) host species, even in indigobirds that normally parasitized other hosts. This innate call is used by nestlings to gain parental care. Both kinds of begging calls are used by adults in mate choice. Host-specific begging call in mimicry songs of adult male indigobirds would allow females to assess whether males were reared by their own foster species.

Song mimicry, song dialects, and behavioural context of songs in brood-parasitic Straw-tailed Whydahs, Vidua fischeri

Straw-tailed Whydahs, Vidua fischeri, mimic the songs and calls of their host species, the Purple Grenadier, Granatina ianthinogaster, and they also have songs that do not mimic the hosts. Neighbouring male whydahs match song themes with each other, while males a few km distant have another set of song themes. Certain song themes were given associated with aggressive contexts and sexual displays (three themes in sustained chase of an intruding male, four other themes in display to a visiting female). Song matching among neighbouring male whydahs is similar to that in Village Indigobirds, V. chalybeata, and suggests that social organisation is similar in the whydahs and indigobirds. A few males have songs like those of distant males and those songs are apparent markers of dispersal. The distribution of song behaviour traits among species points to early phylogenetic origins of the elaborate song repertoires and the mimicry of songs of their host species in brood-parasitic Vidua finches.