The evolution of carotenoid coloration in estrildid finches: a biochemical analysis

The estrildid finches (Aves: Passeriformes: Estrildidae) of Africa, Asia, and Australia have been the focus of several recent tests of sexual selection theory. Many estrildids display bright red, orange, or yellow colors in the beak or plumage, which typically are generated by the presence of carotenoid pigments. In this study, we used high-performance liquid chromatography to investigate the carotenoid content of feathers and other colorful tissues in seven species of estrildids. Star finches (Neochmia ruficauda) and diamond firetails (Stagonopleura guttata) circulated two main dietary carotenoids (lutein and zeaxanthin) through the blood and liver and used both to acquire a yellow plumage color. However, five other estrildids (common waxbill, Estrilda astrild; black-rumped waxbill, Estrilda troglodytes; zebra waxbill, Amandava subflava; red avadavat, Amandava amandava; and zebra finch, Taeniopygia guttata) circulated these same dietary carotenoids along with two metabolites (dehydrolutein and anhydrolutein) through the blood and/or liver and used all four as yellow plumage colorants. We subsequently tracked the distribution of these pigments using a published phylogeny of estrildid finches to determine the evolutionary pattern of carotenoid metabolism in these birds. We found that finches from the most ancient tribe of estrildids (Estrildini) possessed the ability to metabolize dietary carotenoids. Although carotenoids from the most ancestral extant estrildid species have yet to be analyzed, we hypothesize (based on their relationships with other songbirds known to have such metabolic capabilities) that these finches inherited from their ancestors the capability to metabolize carotenoids. Interestingly, later in estrildid evolution, certain taxa lost the ability to metabolize dietary carotenoids (e.g., in the Poephilini), suggesting that the occurrence of carotenoid metabolism can be labile and is likely shaped by the relative costs and benefits of color signaling across different species.     

Evolution of the ovenbird-woodcreeper assemblage (Aves: Furnariidae) - major shifts in nest architecture and adaptive radiation

The Neotropical ovenbirds (Furnariidae) form an extraordinary morphologically and ecologically diverse passerine radiation, which includes many examples of species that are superficially similar to other passerine birds as a resulting from their adaptations to similar lifestyles. The ovenbirds further exhibits a truly remarkable variation in nest types, arguably approaching that found in the entire passerine clade. Herein we present a genus-level phylogeny of ovenbirds based on both mitochondrial and nuclear DNA including a more complete taxon sampling than in previous molecular studies of the group. The phylogenetic results are in good agreement with earlier molecular studies of ovenbirds, and supports the suggestion that Geositta and Sclerurus form the sister clade to both core-ovenbirds and woodcreepers. Within the core-ovenbirds several relationships that are incongruent with traditional classifications are suggested. Among other things, the philydorine ovenbirds are found to be non-monophyletic. The mapping of principal nesting strategies onto the molecular phylogeny suggests cavity nesting to be plesiomorphic within the ovenbird–woodcreeper radiation. It is also suggested that the shift from cavity nesting to building vegetative nests is likely to have happened at least three times during the evolution of the group. We suggest that the shifts in nest architecture within the furnariine and synallaxine ovenbirds have served as an ecological release that has facilitated diversification into new habitats and new morphological specializations.     

An endemic radiation of Malagasy songbirds is revealed by mitochondrial DNA sequence data

The bird fauna of Madagascar includes a high proportion of endemic species, particularly among passerine birds (Aves: Passeriformes). The endemic genera of Malagasy songbirds are not allied obviously with any African or Asiatic taxa, and their affinities have been debated since the birds first were described. We used mitochondrial sequence data to estimate the relationships of 13 species of endemic Malagasy songbirds, 17 additional songbird species, and one species of suboscine passerine. In our optimal trees, nine of the 13 Malagasy species form a clade. although these birds currently are classified in three different families. In all optimal trees, the sister to this endemic clade is a group of Old World warblers including both African and Malagasy birds. The endemic Malagasy songbird clade rivals other island radiations, including the vangas of Madagascar and the finches of the Galapagos, in ecological diversity.     

A Molecular Phylogeny of Warbling-Finches (Poospiza): Paraphyly in a Neotropical Emberizid Genus

We investigated the phylogenetic relationships of 12 species within a single genus of neotropical passerine (Poospiza) using 849 bp (283 codons) of the cytochrome b mitochondrial gene. We further explored evolutionary affinities of these taxa using sequence from an additional 47 thraupine (tanagers) and 7 emberizine (sparrows and buntings) genera, members of the predominantly New World family Emberizidae. Poospiza have traditionally been considered part of the emberizine radiation. However, our analyses suggest that members of this genus are more closely related to some thraupine lineages than they are to the other neotropical emberizine genera included in our study (Atlapetes, Embernagra, Melopyrrha, Phrygilus, Saltatricula, Tiaris). Although member taxa are closely related, the genus Poospiza appears to be paraphyletic with representatives of 6 thraupine genera (Cnemoscopus, Cypsnagra, Hemispingus, Nephelornis, Pyrrhocoma, Thylpopsis) interspersed among four well-supported Poospiza clades. The majority of species within this Poospiza–thraupine clade have geographic ranges that are exclusive to, or partially overlap with, the Andes Mountains. It is probable that these mountains have played an important role in driving cladogenesis within this group. Sequence divergence (transversions only; mean 4.7 ± 1.3%) within the clade suggests that much of this diversification occurred within the late Miocene and Pliocene, a period coincident with major orogenic activity in central-western South America.     

Duplication of accelerated evolution and growth hormone gene in passerine birds

We report the discovery of a duplication of the growth hormone (GH) gene in a major group of birds, the passerines (Aves: Passeriformes). Phylogenetic analysis of 1.3-kb partial DNA sequences of GH genes for 24 species of passerines and numerous outgroups indicates that the duplication occurred in the ancestral lineage of extant passerines. Both duplicates and their open-reading frames are preserved throughout the passerine clade, and both duplicates are expressed in the zebra finch brain, suggesting that both are likely to be functional. The estimated rates of amino acid evolution are more than 10-fold higher in passerine GH genes than in those of their closest nonpasserine relatives. In addition, although the 84 codons sequenced are generally highly conserved for both passerines and nonpasserines, comparisons of the nonsynonymous/synonymous substitution ratios and the rate of predicted amino acid changes indicate that the 2 gene duplicates are evolving under different selective pressures and may be functionally divergent. The evidence of differential selection, coupled with the preservation of both gene copies in all major lineages since the origin of passerines, suggests that the duplication may be of adaptive significance, with possible implications for the explosive diversification of the passerine clade.     

A molecular phylogeny of warbling-finches (Poospiza): paraphyly in a neotropical Emberizid genus

We investigated the phylogenetic relationships of 12 species within a single genus of neotropical passerine (Poospiza) using 849 bp (283 codons) of the cytochrome b mitochondrial gene. We further explored evolutionary affinities of these taxa using sequence from an additional 47 thraupine (tanagers) and 7 emberizine (sparrows and buntings) genera, members of the predominantly New World family Emberizidae. Poospiza have traditionally been considered part of the emberizine radiation. However, our analyses suggest that members of this genus are more closely related to some thraupine lineages than they are to the other neotropical emberizine genera included in our study (Atlapetes, Embernagra, Melopyrrha, Phrygilus, Saltatricula, Tiaris). Although member taxa are closely related, the genus Poospiza appears to be paraphyletic with representatives of 6 thraupine genera (Cnemoscopus, Cypsnagra, Hemispingus, Nephelornis, Pyrrhocoma, Thylpopsis) interspersed among four well-supported Poospiza clades. The majority of species within this Poospiza-thraupine clade have geographic ranges that are exclusive to, or partially overlap with, the Andes Mountains. It is probable that these mountains have played an important role in driving cladogenesis within this group. Sequence divergence (transversions only; mean 4.7+/-1.3%) within the clade suggests that much of this diversification occurred within the late Miocene and Pliocene, a period coincident with major orogenic activity in central-western South America.     

Are levels of digestive enzyme activity related to the natural diet in passerine birds?

Digestive capabilities, such as the rates nutrient hydrolysis and absorption, may affect energy intake and ultimately feeding behavior. In birds, a high diversity in gut biochemical capabilities seems to support the existence of a correlation between the morphology and physiology of the intestinal tract and chemical features of the natural diet. However, studies correlating the activity of digestive enzymes and the feeding habits at an evolutionary scale are scarce. We investigated the effect of dietary habits on the digestive physiological characteristics of eight species of passerine birds from Central Chile. The Order Passeriformes is a speciose group with a broad dietary spectrum that includes omnivorous, granivorous and insectivorous species. We measured the activity of three enzymes: maltase, sucrase and aminopeptidase-N. Using an autocorrelation analysis to remove the phylogenetic effect, we found that dietary habits had no effect on enzymatic activity. However, we found that granivorous and omnivorous species had higher levels of disaccharidase activities and insectivores had the lowest. The major difference in enzymatic activity found at the inter-specific level, compared to the reported lower magnitude of enzyme modulation owing to dietary acclimation, suggests that these differences to some extent have a genetic basis. However, the lack of a clear association between diet categories and gut physiology suggested us that dietary categorizations do not always reflect the chemical composition of the ingested food.     

The phylogenetic position of the world's smallest passerine,the Pygmy Bushtit Psaltria exilis

The Pygmy Bushtit is confined to the montane forests of Java. It is the world's smallest passerine and morphologically resembles a small, drab long‐tailed tit or bushtit (Aegithalidae). In its behaviour the Pygmy Bushtit show similarities with the members of the Aegithalidae, but owing to its small size and isolated geographical distribution relative to the other members of the Aegithalidae, it has always been placed in a monotypic genus within the family. The affinities of the Pygmy Bushtit have never been tested in a phylogenetic context and the species has to date not been included in any molecular studies. In this study we use sequence data from four different genetic markers to place it in the passerine phylogenetic tree. Our results confirm the inclusion of the Pygmy Bushtit in the Aegithalidae, but rather than being an isolated lineage, our results strongly suggest that it is nested in the Aegithalos clade, and most closely related to the Black‐throated Bushtit Aegithalos concinnus. The range of the Black‐throated Bushtit extends south into subtropical Indochina, with an isolated subspecies occurring in southern Vietnam. The Black‐throated Bushtit contains several morphologically and genetically distinct lineages, which could represent distinct species, but the phylogenetic relationships within this complex are poorly resolved and partly in conflict with current taxonomic treatment based on morphology.     

Molecular systematics of a speciose, cosmopolitan songbird genus: defining the limits of, and relationships among, the Turdus thrushes

The avian genus Turdus is one of the most speciose and widespread of passerine genera. We investigated phylogenetic relationships within this genus using mitochondrial DNA sequence data from the ND3, ND2 and cytochrome b genes. Our sampling of Turdus included 60 of the 65 extant species currently recognized, as well as all four species from three genera previously shown to fall inside Turdus (Platycichla, Nesocichla, and Cichlherminia). Phylogenetic trees based on maximum likelihood and maximum parsimony algorithms were congruent. Most of the Turdus taxa sampled fall into one of four clades: an African clade, a Central American-Caribbean clade, a largely South American clade, and a Eurasian clade. Still other taxa are placed either at the base of Turdus, or as links between clades. In no instance is any continent reciprocally monophyletic for the species distributed on it. A general lack of nodal support near the base of the phylogeny seems related to a rapid intercontinental establishment of the major clades within Turdus very early in the history of the genus. The monotypic genus Psophocichla is distantly related to, but clearly the sister of, Turdus rather than a constituent member of it.     

辽宁老铁山雀形目鸟类秋季迁徙初探

2000~2004年秋在辽宁旅顺老铁山自然保护区,通过鸟类环志和直接观察的方法,对该地区雀形目(Passeriformes)鸟类秋季迁徙规律进行了研究。5年共环志11 040只雀形目鸟类,发现8种保护区新记录种。结果表明,鸟类迁徙高峰大都集中在10月中下旬;气候条件与鸟类迁徙关系密切;不同年份优势种及种群数量均不同;鸟类的迁徙具有一定的顺序性和集群现象,但不同种类迁徙的种群大小又有差别;2004年雀形目鸟类的种类和数量都明显少于前4年,略有下降趋势。     

Evolution, biogeography, and patterns of diversification in passerine birds

This paper summarizes and discusses the many new insights into passerine evolution gained from an increased general interest in avian evolution among biologists, and particularly from the extensive use of DNA sequence data in phylogenetic reconstruction. The sister group relationship between the New Zealand rifleman and all other passerines, indicates the importance of the former southern supercontinent Gondwana in the earliest evolution of this group. Following the break-up of Gondwana, the ancestors of other major passerine groups became isolated in Australia (oscines), South America (New World suboscines), and possibly, the then connected Kerguelen Plateau/India/Madagascar tectonic plates (Old World suboscines). The oscines underwent a significant radiation in the Australo-Papuan region and only a few oscine lineages have spread further than to the nearby Southeast Asia. A remarkable exception is the ancestor to the vast Passerida radiation, which now comprises 35% of all bird species. This group obviously benefitted greatly from the increased diversity in plant seed size and morphology during the Tertiary. The lyrebirds (and possibly scrub-birds) constitute the sister group to all other oscines, which renders "Corvida" ( sensu Sibley and Ahlquist 1990) paraphyletic. Sequence data suggests that Passerida, the other clade of oscines postulated based on the results of DNA–DNA hybridizations, is monophyletic, and that the rockfowl and rock-jumpers are the most basal members of this clade. The suboscines in the Old World (Eurylamides) and the New World (Tyrannides), respectively, are sister groups. A provisional, working classification of the passerines is presented based on the increased understanding of the major patterns of passerine evolution.     

Global diversification rates of passerine birds

The distribution of species richness in families of passerine birds suggests that the net rate of diversification was significantly higher than average in as many as 7 out of 47 families. However, the absence of excess species richness among the 106 tribes within these families indicates that these high rates were transient, perhaps associated in some cases with tectonic movements or dispersal events that extended geographical ranges. Thus, large clade size among passerine birds need not represent intrinsic key innovations that influence the rate of diversification. Approximately 17 families and 30 tribes have too few species relative to other passerine taxa. Many of these are ecologically or geographically marginal, being especially overrepresented in the Australasian region. Observed intervals between lineage splitting suggest that extinction has occurred ca. 90% as frequently as speciation (waiting times of 1.03 and 0.93 Myr) and that the 47 modern families comprising 5712 species descended from approximately 430 passerine lineages extant 24 Myr ago. Speciation and extinction rates among small, marginal families might be 1-2 orders of magnitude lower.     

A single ancient origin of brood parasitism in African finches: implications for host-parasite coevolution

Robust phylogenies for brood-parasitic birds, their hosts, and nearest nesting relatives provide the framework to address historical questions about host-parasite coevolution and the origins of parasitic behavior. We tested phylogenetic hypotheses for the two genera of African brood-parasitic finches, Anomalospiza and Vidua, using mitochondrial DNA sequence data from 43 passeriform species. Our analyses strongly support a sister relationship between Vidua and Anomalospiza, leading to the conclusion that obligate brood parasitism evolved only once in African finches rather than twice, as has been the conventional view. In addition, the parasitic finches (Viduidae) are not recently derived from either weavers (Ploceidae) or grassfinches (Estrildidae), but represent a third distinct lineage. Among these three groups, the parasitic finches and estrildids, which includes the hosts of all 19 Vidua species, are sister taxa in all analyses of our full dataset. Many characters shared by Vidua and estrildids, including elaborate mouth markings in nestlings, unusual begging behavior, and immaculate white eggs, can therefore be attributed to common ancestry rather than convergent evolution. The host-specificity of mouth mimicry in Vidua species, however, is clearly the product of subsequent host-parasite coevolution. The lineage leading to Anomalospiza switched to parasitizing more distantly related Old World warblers (Sylviidae) and subsequently lost these characteristics. Substantial sequence divergence between Vidua and Anomalospiza indicates that the origin of parasitic behavior in this clade is ancient (approximately 20 million years ago), a striking contrast to the recent radiation of extant Vidua. We suggest that the parasitic finch lineage has experienced repeated cycles of host colonization, speciation, and extinction through their long history as brood parasites and that extant Vidua species represent only the latest iterations of this process. This dynamic process may account for a significantly faster rate of DNA sequence evolution in parasitic finches as compared to estrildids and other passerines. Our study reduces by one the tally of avian lineages in which obligate brood parasitism has evolved and suggests an origin of parasitism that involved relatively closely related species likely to accept and provide appropriate care to parasitic young. Given the ancient origin of parasitism in African finches, ancestral estrildids must have been parasitized well before the diversification of extant Vidua, suggesting a long history of coevolution between these lineages preceding more recent interactions between specific hosts and parasites.     

Complete mitochondrial genomes of prasinophyte algae Pyramimonas parkeae and Cymbomonas tetramitiformis

Mitochondria are archetypal eukaryotic organelles that were acquired by endosymbiosis of an ancient species of alpha‐proteobacteria by the last eukaryotic common ancestor. The genetic information contained within the mitochondrial genome has been an important source of information for resolving relationships among eukaryotic taxa. In this study, we utilized mitochondrial and chloroplast genomes to explore relationships among prasinophytes. Prasinophytes are represented by diverse early‐diverging green algae whose physical structures and genomes have the potential to elucidate the traits of the last common ancestor of the Viridiplantae (or Chloroplastida). We constructed de novo mitochondrial genomes for two prasinophyte algal species, Pyramimonas parkeae and Cymbomonas tetramitiformis, representing the prasinophyte clade. Comparisons of genome structure and gene order between these species and to those of other prasinophytes revealed that the mitochondrial genomes of P. parkeae and C. tetramitiformis are more similar to each other than to other prasinophytes, consistent with other molecular inferences of the close relationship between these two species. Phylogenetic analyses using the inferred amino acid sequences of mitochondrial and chloroplast protein‐coding genes resolved a clade consisting of P. parkeae and C. tetramitiformis; and this group (representing the prasinophyte clade I) branched with the clade II, consistent with previous studies based on the use of nuclear gene markers.     

Molecular characterization of isosporoid coccidia (Isospora and Atoxoplasma spp.) in passerine birds

Prevalence and disease caused by isosporoid coccidia in passerine birds are well recognized, but confusion about the life cycles of the parasites has led to taxonomic inconsistencies. In this study, we characterized segments of the chromosomal small and large-subunit ribosomal RNA (rRNA) genes of coccidial parasites from 23 species of passerine birds, as well as heat shock protein 70, apicoplast rRNA, and chromosomal 5.8s rRNA genes from a subgroup of these animals, and we correlated genetic data with morphologic findings for different parasite developmental stages, host phylogeny, and overall taxonomic relations within the phylum Apicomplexa. Our findings indicate that isosporoid coccidia of passerine birds are monophyletic but exhibit substantial diversity, with most avian species having one or several unique parasite lineages that underwent synchronous speciation with their hosts, interrupted by sporadic episodes of lateral transmission across species and families. Molecular analyses support a homoxenous life cycle, with sexual forms occurring chiefly in the intestines and asexual merozoites present systemically. Rarely, extraintestinal sexual stages can occur. The passerine coccidia are genetically most closely related to species of Eimeria rather than Isospora. We suggest that these parasites, whether identified from blood merozoite stages or fecal oocysts, be provisionally grouped as a homogeneous clade of individual species in a single taxon and formally named when reliable criteria allowing reclassification of related genera in the suborder Eimeriina are clarified.     

Effects of maternal diet on fecundity and larval development in the 'primitive' granivorous carabid Amara (Curtonotus) macronota

Granivory is one of the most specialized food habits in the Carabidae and has been reported for species from the tribes Zabrini and Harpalini. Most studies of carabid granivory have been conducted using specialized granivorous species, and few have examined primitive ones. This study examined effects of maternal diet on fecundity and larval development in Amara ( Curtonotus ) macronota (Solsky) (Coleoptera: Carabidae), a member of the most basal clade of the tribe Zabrini; a previous study indicated that larvae of this species are omnivores with a tendency toward carnivory. Three diet types, Tenebrio molitor L. larvae, mixed seeds [ Bidens frondosa L. (Asteraceae), Setaria spp., and Digitaria ciliaris (Retz.) Koeler (both Poaceae)], and T. molitor larvae + mixed seeds, were used as maternal diets, and larvae were reared on T. molitor larvae + mixed seeds (optimal diet) or T. molitor larvae (suboptimal diet). Fecundity differed significantly among treatments, with individuals fed the T. molitor larvae + mixed seeds diet having the highest fecundities and the mixed seeds diet producing the lowest values. Larval development [survival and duration of development through pre-overwintering stages (first and second instars)] was not significantly affected by either maternal or larval diets, but the addition of seeds to the maternal diet had a weak negative effect on larval survival. These results are in contrast with findings from specialized granivorous carabids, in which both adults and larvae performed best with pure-seed diets. Recent molecular phylogenies indicate that these specialized granivorous carabids belong to derived lineages, while A. macronota is the most basal clade of each tribe. These results are compatible with the hypothesis that carabid granivory has evolved gradually from ancestral carnivory, with omnivorous habits occurring as a transient state.     

A phylogeny for the Cisticolidae (Aves: Passeriformes) based on nuclear and mitochondrial DNA sequence data, and a re-interpretation of an unique nest-building specialization

Based on some general similarities in feeding adaptations, a large number of Old World passerine birds were in the past lumped in one broad family, the Sylviidae. Recent molecular studies, starting with the DNA-DNA hybridization work by Sibley et al. [Sibley, C.G., Ahlquist, J.E., 1990. Phylogeny and Classification of Birds: A Study in Molecular Evolution, Yale University Press, New Haven, CT], have revealed that this group is in fact a paraphyletic assemblage, mainly in the superfamily Sylvioidea, and within this assemblage a distinct group (the Cisticolidae) can be identified around the genus Cisticola. In this study we try to define natural lineages within it, based on DNA sequence data from 35 ingroup taxa representing 12 putative genera. Both nuclear myoglobin intron II (630 bp in our study) and mitochondrial ND2 (1041 bp) genes were sequenced, and 1671 bp were aligned and subjected to parsimony, maximum likelihood and Bayesian analyses. The results strongly support the monophyly of a cisticolid clade, with the Malagasy warblers Neomixis constituting the deepest branch within the clade. Three major clades receive statistical support, but not all relationships between and within these are well resolved. All species of the genus Bathmocercus belong to the Cisticolidae but in two different clades. The tailorbirds appear also polyphyletic with most species of the genus Orthotomus (but O. cucullatus falling in the outgroup) and the African metopias being in two different clades. Also the genus Apalis is polyphyletic, but all other included genera seem to be confirmed as natural units. Based on these findings we resurrect the genera Scepomycter and Artisornis. Calamonastes is confirmed to be in the Cisticolidae and grouped with Camaroptera. Main basic nest types do not follow the phylogenetic branching, and notably the peculiar "tailorbird" technique of stitching leaves together around the nest is found in different parts of the phylogeny. The basic types of nests seem to be found in particular environments, and the sewing may therefore have evolved in some ancestor of the Cisticolidae and was later lost or modified in some genera or species following the spread of drier habitats from the mid-Miocene.     

Chromosomal evolution within the family Estrildidae (Aves) III. The Estrildae (waxbill finches)

The C- and G-banded karyotypes of five species of waxbill finches belonging to the Estrildidae were examined. Extensive chromosomal variation including inversions and fissions was found to differentiate the species, showing the waxbills to be the most chromosomally diverse group of estrildid finches. None of the variation, however, matched that recorded in related species of Pytilia (Christidis, 1983). By comparing the G-banded karyotypes of species belonging to all three estrildid lineages it was possible to reconstruct the presumed ancestral karyotype for the Estrildidae as a whole. This was found to approximate the karyotype of the Australian peophilid species, Poephila guttata most closely. From it chromosomal relationships within the three estrildid lineages, Poephilae, Lonchurae, Estrildae, can be determined.     

Multi-locus phylogeny clarifies the systematics of the Australo-Papuan robins (Family Petroicidae, Passeriformes)

The Australo-Papuan family Petroicidae (Aves: Passeriformes) has been the focus of much systematic debate about its relationships with other passerine families, as well as relationships within the family. Mostly conservative morphology within the group limits the effectiveness of traditional taxonomic analyses and has contributed to ongoing systematic debate. To assess relationships within the family, we sampled 47 individuals from 26 species, representing the majority of genera and species, for four loci: 528 base pairs (bp) of C-myc, 501 bp of BA20454 and 336 bp of BA23989 from nuclear DNA and 1005 bp of the mitochondrial ND2 gene. There was consensus between individual loci and overall support for major lineages was strong. Partitioned Bayesian analyses of all four loci produced a fully resolved and very well-supported phylogeny that addresses many of the previous systematic debates in this group. The Eopsaltriinae as construed is monophyletic with the exception of Eopsaltria flaviventris, which is nested within Microeca as an unremarkable member of that genus. This relationship is corroborated by morphology and egg color and pattern. Petroicinae as currently construed was not monophyletic and comprised two lineages that are paraphyletic with respect to each other. The third subfamily, Drymodinae, remains incertae sedis. The mangrove robin, Peneonanthe pulverulenta, of tropical Australia and New Guinea is nested within a clade that also contained the sampled species of Peneothello and Melanodryas, a novel relationship. Preliminary biogeographic and divergence time estimates from these results are discussed and a new subfamily arrangement proposed.     

Passerine abundance and diversity in a polluted oasis habitat in south-eastern Tunisia

Gabès region, in south-eastern Tunisia, is nowadays considered as one of the most remarkable pollution hotspots in the Mediterranean due to the emissions of the Gabès-Ghannouche factory complex of phosphate treatment. However, because of the lack of detailed studies, the impact of such pollution on the terrestrial wildlife inhabiting this area still remains unknown. In this work, we checked whether the proximity to Gabès-Ghannouche factory complex was associated with a decreased abundance of passerines breeding in the neighbouring oasis habitat. Overall, passerine abundance was found to decrease in the proximity of the factory complex, but this decrease was more pronounced in insectivorous species than in granivorous ones. The latter species seemed to be more dependent on vegetation structure. Moreover, we found that in the sites close to the factory complex, the studied passerine community was dominated by the Sparrow Passer domesticus × hispaniolensis, which seemed to be the less sensitive species to pollution. However, in the more distant sites, passerine abundance was more equitably distributed among species due to the increase in the densities of pollution-sensitive ones. Our findings give support to those reported in polluted European forest habitats and stress once again the usefulness of passerines as reliable biomonitors of polluted terrestrial environments.