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Avian Families (avian + family)
Selected AbstractsOccurrence and life history correlates of vocal duetting in North American passerinesJOURNAL OF AVIAN BIOLOGY, Issue 1 2008Lauryn Benedict Vocal duetting, where two birds produce temporally coordinated vocalizations, has been reported in a taxonomically and geographically diverse set of avian species. Researchers have suggested a number of potential correlates of duetting, including long term monogamy, year-round territory defense and sexual plumage monomorphism. Because the majority of duetting species are tropical, they have been the focus of the most comprehensive studies to date. There is, therefore, a real need for data regarding avian duets in temperate species. I used the recently completed Birds of North America species reports to examine the frequency, evolutionary origins and potential life history correlates of duetting behavior in North American passerines. "Duetting" behavior was reported in 7% of species from 12 avian families, likely representing 17 separate evolutionary origins. Duetting species showed apparent long term monogamy and year-round territoriality at frequencies more than double those of non-duetting passerines: 65% of duetting species were long term monogamous, compared to 27% of non-duetting species, and 50% of duetting species defended the same territory throughout the year, compared with only 11% of non-duetting species. Duetting and non-duetting species showed statistically indistinguishable frequencies of sexual plumage monomorphism. Comparative analyses of duetting species and their sister taxa revealed that the shift to duetting is accompanied by a gain of long term monogamy and year-round territoriality more often than it is associated with a loss of those traits. This study provides intriguing summary evidence that selective factors promoting duetting may be associated with a sedentary, monogamous lifestyle, and may operate similarly across taxonomic groups. Furthermore, vocal duetting may be considerably more common among temperate-zone species than previously recognized. [source] Differential rates of morphological divergence in birdsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2004F. Bokma Abstract There are more small-bodied bird species than there are large-bodied, even on a logarithmic scale. In birds this pattern, which is also found in other higher taxa, appears not to be due to neutral evolution. It has often been suggested that the skew of body size frequency distributions is the result of a relationship between body size and the net rate of speciation, but phylogenetic analyses so far have rejected the hypothesis that small-bodied species are subject to higher net rates of speciation. On the contrary, we show that there exists a relationship between body size and its own evolutionary variability: avian families of small body size show less interspecific variation in body size than large-bodied families of similar age and species richness. [source] Fig-eating by vertebrate frugivores: a global reviewBIOLOGICAL REVIEWS, Issue 4 2001MIKE SHANAHAN ABSTRACT The consumption of figs (the fruit of Ficus spp.; Moraceae) by vertebrates is reviewed using data from the literature, unpublished accounts and new field data from Borneo and Hong Kong. Records of frugivory from over 75 countries are presented for 260 Ficus species (approximately 30% of described species). Explanations are presented for geographical and taxonomic gaps in the otherwise extensive literature. In addition to a small number of reptiles and fishes, 1274 bird and mammal species in 523 genera and 92 families are known to eat figs. In terms of the number of species and genera of fig-eaters and the number of fig species eaten we identify the avian families interacting most with Ficus to be Columbidae, Psittacidae, Pycnonotidae, Bucerotidae, Sturnidae and Lybiidae. Among mammals, the major fig-eating families are Pteropodidae, Cercopithecidae, Sciuridae, Phyllostomidae and Cebidae. We assess the role these and other frugivores play in Ficus seed dispersal and identify fig-specialists. In most, but not all, cases fig specialists provide effective seed dispersal services to the Ficus species on which they feed. The diversity of fig-eaters is explained with respect to fig design and nutrient content, phenology of fig ripening and the diversity of fig presentation. Whilst at a gross level there exists considerable overlap between birds, arboreal mammals and fruit bats with regard to the fig species they consume, closer analysis, based on evidence from across the tropics, suggests that discrete guilds of Ficus species differentially attract subsets of sympatric frugivore communities. This dispersal guild structure is determined by interspecific differences in fig design and presentation. Throughout our examination of the fig-frugivore interaction we consider phylogenetic factors and make comparisons between large-scale biogeographical regions. Our dataset supports previous claims that Ficus is the most important plant genus for tropical frugivores. We explore the concept of figs as keystone resources and suggest criteria for future investigations of their dietary importance. Finally, fully referenced lists of frugivores recorded at each Ficus species and of Ficus species in the diet of each frugivore are presented as online appendices. In situations where ecological information is incomplete or its retrieval is impractical, this valuable resource will assist conservationists in evaluating the role of figs or their frugivores in tropical forest sites. [source] Mating system, philopatry and patterns of kinship in the cooperatively breeding subdesert mesite Monias benschiMOLECULAR ECOLOGY, Issue 11 2005N. SEDDON Abstract In the first molecular study of a member of the threatened avian family, Mesitornithidae, we used nine polymorphic microsatellite loci to elucidate parentage, patterns of within-group kinship and occurrence of extra-group paternity in the subdesert mesite Monias benschi, of southwest Madagascar. We found this cooperatively breeding species to have a very fluid mating system. There was evidence of genetic monogamy and polygynandry: of the nine groups with multiple offspring, six contained one breeding pair with unrelated helpers and three contained multiple male and female breeders with related helpers. Although patterns of within-group kinship varied, there was a strong positive relationship between group size and relatedness, suggesting that groups form by natal philopatry. There was also a strong positive correlation between within-sex and between-sex relatedness, indicating that unlike most cooperatively breeding birds, philopatry involved both sexes. In contrast to predictions of kin selection and reproductive skew models, all monogamous groups contained unrelated individuals, while two of the three polygynandrous groups were families. Moreover, although between-group variation in seasonal reproductive success was related to within-group female relatedness, relatedness among males and between the sexes had no bearing on a group's reproductive output. While kin selection may underlie helping behaviour in females, factors such as direct long-term fitness benefits of group living probably determine helping in males. Of the 14 offspring produced by fully sampled groups, at least two were sired by males from neighbouring groups: one by a breeding male and one by a nonbreeding male, suggesting that males may augment their reproductive success through extra-group paternity. [source] TWO NEW PARROTS (PSITTACIFORMES) FROM THE LOWER EOCENE FUR FORMATION OF DENMARKPALAEONTOLOGY, Issue 3 2008DAVID M. WATERHOUSE Abstract:, Two new fossil psittaciform birds from the Lower Eocene ,Mo Clay' (Fur Formation) of Denmark (c. 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudasturidae (genus and species incertae sedis), while a second (Mopsitta tanta gen. et sp. nov.) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic position of Mopsitta is unclear (it is classified as family incertae sedis), this form is phylogenetically closer to Recent Pstittacidae than to other known Palaeogene psittaciforms and may, therefore, represent the oldest known crown-group parrot. [source] | ||||||||||