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Extreme Endemic Radiation of the Malagasy Vangas (Aves: Passeriformes)
Abstract
Phylogenetic relationships of the family Vangidae and representatives of several other passeriform families were inferred from 882 base positions of mitochondrial DNA sequences of 12S and 16S rRNA genes. Results indicated the monophyly of the Vangidae, which includes the genus Tylas, hitherto often placed in the family Pycnonotidae. Our results also revealed the Malagasy endemic Newtonia, a genus never previously assigned to the Vangidae, to be a member of this family. These results suggest the occurrence of an extensive in situ radiation of this family within Madagascar, and that the extant high diversity of this family is not the result of multiple colonizations from outside. The extremely high morphological and ecological diversification of the family seems to have been enhanced through the use and ultimate occupancy of vacant niches in this island.
... Schetba, or the Rufous Vanga, is a monotypic genus within an endemic Malagasy radiation of songbirds, the Vangidae (Yamagishi et al., 2001;Reddy et al., 2012;Jønsson et al., 2012). The current taxonomy of the genus comprises a single species, S. rufa, with two subspecies: S. r. rufa (Linnaeus, 1766) and S. r. occidentalis (Delacour, 1931). ...
... However, the degree of divergence between these subspecies, which are based on slight differences in bill dimensions and plumage, has not been corroborated with genetic or ecological data. Previous genetic studies each included only a single representative of S. rufa (Yamagishi et al., 2001;Jønsson et al., 2012;Reddy et al., 2012). Furthermore, the distributional limits of S. r. occidentalis and S. r. rufa are somewhat ill-defined and might be attributed to clinal variation (Delacour, 1932;Schulenberg, 2013). ...
Madagascar is known as a biodiversity hotspot, providing an ideal natural laboratory for investigating the processes of avian diversification. Yet, the phylogeography of Madagascar's avifauna is still largely unexamined. In this study, we evaluated phylogeographic patterns and species limits within the Rufous Vanga, Schetba rufa, a monotypic genus of forest-dwelling birds endemic to the island. Using an integrative taxonomic approach, we synthesized data from over 4000 ultra-conserved element (UCE) loci, mitochondrial DNA, multivariate morphometrics, and ecological niche modeling to uncover two reciprocally monophyletic, geographically circumscribed, and morphologically distinct clades of Schetba. The two lineages are restricted to eastern and western Madagascar, respectively, with distributions broadly consistent with previously described subspecies. Based on their genetic and morphological distinctiveness, the two subspecies merit recognition as separate species. The bioclimatic transition between the humid east and dry west of Madagascar likely promoted population subdivision and drove speciation in Schetba during the Pleistocene. Our study is the first evidence that an East-West bioclimatic transition zone played a role in the speciation of birds within Madagascar.
... The few systematic studies of Malagasy birds have produced astounding findings, most prominently the discovery of the spectacular in situ radiation of the Malagasy Vangidae (Jønsson et al., 2012;Reddy et al., 2012). This monophyletic assemblage consists of at least 22 species, many of which were originally placed in other families, and is nearly as morphologically diverse as all passerines combined (Jønsson et al., 2012;Reddy et al., 2012;Yamagishi et al., 2001). Furthermore, a group of 11 species previously placed in three different families was found to represent another monophyletic avian assemblage endemic to Madagascar (Cibois et al., 2001), and now comprises the recently described family Bernieridae (Cibois et al., 2010). ...
... The genus Newtonia is a group of small, forest-dwelling songbirds endemic to Madagascar. Newtonia were originally classified as either Old World warblers (Sylviidae) or flycatchers (Muscicapidae), but are now known to belong to the Vangidae radiation (Reddy et al., 2012;Yamagishi et al., 2001). The current taxonomy delineates four species. ...
... Transitions to novel habitats have catalyzed a highlight reel of biological diversification (Simpson 1953;Schluter 2000;Stroud and Losos 2016). Bellflowers (subfamily Lobelioideae) radiating on the Hawaiian archipelago, cichlids (subfamily Pseudocrenilabrinae) in African rift lakes, and vanga birds (family Vangidae) on Madagascar are classic examples (Yamagishi et al. 2001;Seehausen 2006;Givnish et al. 2009). Freshwater invasions by marine fishes provide extreme examples of such habitat-driven diversification (Carrete Vega and Wiens 2012). ...
Invasions of freshwater habitats by marine fishes provide exceptional cases of habitat-driven biological diversification. Freshwater habitats make up less than 1% of aquatic habitats but contain ∼50% of fish species. However, while the dominant group of freshwater fishes (Otophysi) is older than that of most marine fishes (Percomorphaceae), it is less morphologically diverse. Classically, scientists have invoked differences in the tempo and/or mode of evolution to explain such cases of unequal morphological diversification. We tested for evidence of these phenomena in the superfamily Cottoidea (sculpins), which contains substantial radiations of marine and freshwater fishes. We find that the morphology of freshwater sculpins evolves faster but under higher constraint than that of marine sculpins, causing widespread convergence in freshwater sculpins and more morphological disparity in marine sculpins. The endemic freshwater sculpins of Lake Baikal, Siberia, are exceptions that demonstrate elevated novelty akin to that of marine sculpins. Several tantalizing factors may explain these findings, such as differences in habitat stability and/or habitat connectivity between marine and freshwater systems.
... Similarly, the 15-21 vanga species of Madagascar also probably evolved from a monophyletic group of shrike-like birds from the Old World tropics (Reddy et al. 2012). Today, some Madagascar vangas possess sharp bills for killing prey such as lizards and frogs; however, some vangas have evolved short thin bills for capturing insects in flight, whereas others have heavily curved bills for probing cracks and holes in search of hidden invertebrates (Yamagishi et al. 2001). Three sympatric crossbill species in northern latitudes have evolved bills of three different sizes, which correspond with the size of specific conifer seeds of different species that they consume, using their uniquely matched bills to extract the seeds from the cones (Marquiss and Rae 2002). ...
Feeding morphology permits animals to adapt to changing environments and is often under strong selection. We evaluated if bill shape varies according to differences in dietary prey taken across geographical ranges (North America, Central America, South America, and Caribbean islands) in a ubiquitous, New World raptor species, the American kestrel (Falco sparverius). Specifically, we predicted that bills in geographies where kestrels consumed a larger proportion of vertebrates would be shorter and wider, with a larger tomial tooth. We reviewed the literature on kestrel diets across their range and quantified potential differences in bill shape using geometric morphometric methods for 245 museum specimens. The literature review revealed that most prey consumed by kestrels in North, South, and Central America were invertebrates (51.6–69.1%), whereas Caribbean kestrels consumed mostly vertebrates (61.4%), most of which were reptiles (77.3%). Morphometric analyses agreed with these findings; bill shape differed for island versus mainland kestrels but not among mainland regions. Bill shape on islands reflected a more robust bill with a larger tomial tooth, but had a longer hook, which we suggest is adaptive for consumption of lizard prey, more available on islands due to reduced competition with other raptors compared to mainland regions.
... More than 110 bird species are endemic to this region (Hawkins et al., 2015). Madagascar's bird diversity generally evolved in two ways, either through adaptive radiation or via multiple immigration (Yamagishi, 2001), which eventually resulted in aforementioned six endemic bird families: the Malagasy warblers (Bernieridae), ground rollers (Brachypteraciidae), cuckoo rollers (Leptosomidae), mesites (Mesitornithidae), asities (Philepittidae) and the vangas (Vangidae), containing a total of 45 species. Another ten genera with a total of 21 bird species are endemic to Madagascar, and there are 31 subspecies of birds found in Madagascar. ...
We investigated for which threatened endemic Malagasy bird species zoo populations already exist, and which threatened species are not yet covered by ex situ conservation measures. To gain an overview of Malagasy bird species held in zoos, the number of individuals kept, the number of keeping institutions and successful reproduction within the last 12 months were analysed based on collection information from ZIMS database (Species360, Bloomington, MN, USA), supplemented with data from ZTL (List of Zoo Animals: https://zootierliste.de/). Of the 195 Malagasy bird species, 142 occur exclusively in the Malagasy region, comprising Madagascar and surrounding islands, and 117 are endemic to Madagascar. Currently, 28 (24%) of the endemic Malagasy bird species are evaluated as threatened, of which two are Critically Endangered, 11 Endangered and 15 Vulnerable according to IUCN. A total of 131 institutions worldwide kept at least one of the 15 endemic Malagasy bird species held. Three of the fi fteen endemic Malagasy bird species held are threatened, of which one is Critically Endangered and two are Endangered according to IUCN. Thus, according to our analysis 25 (89%) of the 28 threatened endemic Malagasy bird species are not covered by ex situ populations. According to ZIMS database, a total of eight of the fi fteen en-demic Malagasy bird species kept in zoos worldwide had successfully reproduced within the last *Corresp. author: E-Mail: ziegler@koelnerzoo.de (Thomas Ziegler) doi:10.53188/zg006 122 R. Lammers et al. · Malagasy birds in zoological gardens 12 months, with three of them being threatened. A richness analysis, which was performed to fi nd out how zoos keeping Malagasy birds are distributed in a global scale, revealed that current zoo collections of threatened endemic Malagasy bird species are mainly concentrat ed in Europe and North America. A protected area coverage analysis, viz. a comparison of the distribution of protected areas with localities of endemic and threatened endemic species, showed that the existing protected area system does not provide enough coverage for several threatened endemic species. We have made recommendations for the shift from non-threatened species such as Bubulcus ibis to threatened species such as Ardeola idae. Species from endemic families should be the focus of new ex situ husbandry and the keeping of Critically Endangered species should be included (e.g., Haliaeetus vociferoides) or expanded (e.g., Aythya innotata). For these species, experience from past husbandry, both positive and negative, or experience from the keeping of closely related species is available. Our fi ndings thus can be used as a guideline to improve zoo collections and to expand the conservation breeding network for threatened endemic Malagasy birds which is in accordance with the One Plan Approach proposed by the IUCN SSC Conservation Planning Specialist Group (CPSG).
... In contrast, phylogeographic studies associated with in situ differentiation on Madagascar, after colonization successfully took place, are uncommon and speciation patterns are still poorly understood for birds. Yamagishi et al. (2001) studied the species-level relationships among the Vangidae, an endemic radiation of Malagasy corvoids that probably dates back to the Oligocene (Fuchs et al. 2006). Marks and Willard (2005) recently addressed the geographic origin of the Madagascar Pygmy Kingfisher (Ispidina madagascariensis). ...
A recent taxonomic revision of the Malagasy Scops-Owl (Otus rutilus) recognized two distinct endemic species on the island based on plumage, vocal, and morphological characters: O. rutilus (sensu stricto) from eastern humid forest formations and O. madagascariensis from western dry forest areas. An evaluation of these characters calls into question their validity for taxonomic studies, as they may be ecologically linked. To independently assess the two-species hypothesis, we used sequence data from 1449 base pairs (bp) of mitochondrial DNA (mtDNA) from 34 scops-owls obtained across the range of these two putative species. Nineteen haplotypes were detected, four of which were shared by more than one individual. Maximum sequence divergence was 0.6% (mean = 0.24%). While the most common haplotype was shared by 10 individuals originating from different eastern and western localities, 12 haplotypes were exclusive to O. rutilus and five to O. madagascariensis. An analysis of molecular variance showed significant partitioning of the genetic variability between O. rutilus and O. madagascariensis. The estimate of the divergence time between populations associated with the names O. rutilus and O. madagascariensis was 8070 years BP. Based on haplotype frequencies and sequence divergence, we conclude that there are two populations of Otus on Madagascar that started to diverge in recent geological time following an ecological parapatric model, perhaps associated with Quaternary climatic shifts. Using these results, it is inappropriate to recognize two species of Otus on Madagascar.
... Vangas exhibited rapid speciation following the initial colonization of the island by a shared ancestor and now provide a prime example of adaptive radiation, with considerable variation in body size and shape (Yamagishi et al. 2001;Jønsson et al. 2012;Reddy et al. 2012). These morphological differences can provide useful clues to the means by which sympatric congeners achieve ecological segregation according to food niche. ...
The common ancestry of congeneric species implies that their morphology and ecology are similar, and thus that these closely related species may experience intensified levels of competition when sympatrically distributed. Under such circumstances, selective pressure may lead to niche partitioning between and within species, with segregation achieved through variation in morphology, ecology and life history. Examining the mechanisms underlying the coexistence or segregation of congeneric species requires detailed data on aspects of their ecology such as their feeding behaviour or habitat use. Endemic island birds, such as the vangas of Madagascar, are good candidates for studying processes of niche segregation. Vangas underwent rapid speciation following the initial colonization of the island by a shared ancestor and now provide a prime example of adaptive radiation, with considerable variation in body size and shape. Four small species of Newtonia are an exception to this variation, as they show morphological overlap and partial spatial range sympatry. Here, we describe the morphology of two Newtonia species, the Common Newtonia Newtonia brunneicauda and Dark Newtonia Newtonia amphichroa, with respect to their ecology and trophic niches using a multi-isotope approach (stable isotope ratios of carbon, nitrogen and sulphur). We report evidence for adaptations involving morphological feeding traits and provide data on contrasting trophic niches between two species with a close phylogenetic relationship. We document micro-habitat niche specialization that may be due to vertical stratification within the forest. Differences in feather isotopic signatures indicate different nutrient sources and point towards microhabitat segregation that is sufficient to maintain species integrity and permit coexistence.
... The Helmet Vanga Euryceros prevostii belongs to the family Vangidae, which contains 22 species in 15 genera (Jønsson et al. 2012). They are well-known for their ecological radiation, resembling that of the Hawaiian honeycreepers and the Galapagos finches (Yamagishi et al. 2001, Grant & Grant 2008, Jønsson et al. 2012, Reddy et al. 2012. The Helmet Vanga is one of the largest and most striking members of the Vangidae. ...
To determine the mating system of the endemic Helmet Vanga Euryceros prevostii in Madagascar, its nest-building behavior was studied from 27 September to 11 October 2015 on the Masoala Peninsula, Northeastern Madagascar. We found one nest which was open cup-shaped placed on the horizontal branch of a tree. Two birds were individually identified through differences in the spot and shape of the mandible. The two birds (probably male and female) made the nest. This result suggests that the Helmet Vanga is a socially monogamous species.
... A sampling of recent findings within the passerines indicates that: -the southern origins of Oscine passerines is supported, with the New Zealand Wrens (Acanthisittidae) representing an ancient relict forming a sister group to all other passerines (Ericson et al. 2002a;Barker et al. 2002); -the monophyly of the two clades of New World suboscines is gaining clarification (Prum et al. 2000;Irestedt et al. 2001;Birdsley 2002), but with recent evidence demonstrating that two genera traditionally placed in Rhinocryptidae probably represent a separate family of uncertain relationships, the newly proposed Melanopareiidae ; -the lyrebirds (and probably scrub-birds) are the most basal group of the Oscines (Ericson et al. 2002b); -the Corvida of Sibley & Ahlquist (1990) is not monophyletic, but their Passerida is (Ericson et al. 2002a;Barker et al. 2002); -Madagascan taxa traditionally assigned to Pycnonotidae, Timaliidae and Sylviidae represent another ancient radiation comparable to the Vangidae, which also includes Newtonia (Fjeldså et al. 1999;Cibois et al. 1999Cibois et al. , 2001Yamagishi et al. 2001); -various New World nine-primaried Oscine taxa traditionally considered as finches prove to be tanagers and vice versa (Burns 1997;Seutin & Bermingham 1997;Groth 1998;Klicka et al. 2000;Lougheed et al. 2000;Garcia-Moreno et al. 2001;Sato et al. 2001;Yuri & Mindell 2002), while the Old World genus Emberiza is not a recent offshoot (Grapputo et al. 2001); -similar outcomes have been found with taxa traditionally considered thrushes or flycatchers, but in some cases their relationships apparently lie elsewhere (Pasquet et al. 1999(Pasquet et al. , 2002; see also Sorensen & Payne 2001); and -taxa traditionally placed in Paridae, Aegithalidae and Sylviidae are closely related (Sturmbauer et al. 1998). ...
The avifauna of Madagascar presents a complicated taxonomic and biogeographic problem. Although Madagascar was once connected to Africa, the birds of the island are not all of African origin. The Madagascar Pygmy Kingfisher (Ispidina madagascariensis) is sometimes placed in the African genus Ispidina and sometimes in the Southeast Asian genus Ceyx. We sequenced 755 base pairs of mitochondrial DNA from a fragment of the NADH dehydrogenase subunit II (ND2) and from the complete NADH dehydrogenase subunit III (ND3). We used these data to construct phylogenetic hypotheses for the Alcedinidae. Using these phylogenies, we evaluate previous hypotheses of relationships of I. madagascariensis. Although we cannot reject the hypothesis that I. madagascariensis is indeed a member of Ispidina, tree-building analyses support a relationship not with Ispidina or Ceyx, but instead with members of the African genus Corythornis. These data suggest that certain behaviors and plumage types have evolved several times in the Alcedinidae.
Relations Phylogénétiques de Ispidina madagascariensis
The complete sequence of the 16,569-base pair human mitochondrial genome is presented. The genes for the 12S and 16S rRNAs, 22 tRNAs, cytochrome c oxidase subunits I, II and III, ATPase subunit 6, cytochrome b and eight other predicted protein coding genes have been located. The sequence shows extreme economy in that the genes have none or only a few noncoding bases between them, and in many cases the termination codons are not coded in the DNA but are created post-transcriptionally by polyadenylation of the mRNAs.
We cloned and sequenced a segment of mitochondrial DNA from human, chimpanzee, gorilla, orangutan, and gibbon. This segment is 896 bp in length, contains the genes for three transfer RNAs and parts of two proteins, and is homologous in all 5 primates. The 5 sequences differ from one another by base substitutions at 283 positions and by a deletion of one base pair. The sequence differences range from 9 to 19% among species, in agreement with estimates from cleavage map comparisons, thus confirming that the rate of mtDNA evolution in primates is 5 to 10 times higher than in nuclear DNA. The most striking new finding to emerge from these comparisons is that transitions greatly outnumber transversions. Ninety-two percent of the differences among the most closely related species (human, chimpanzee, and gorilla) are transitions. For pairs of species with longer divergence times, the observed percentage of transitions falls until, in the case of comparisons between primates and non-primates, it reaches a value of 45. The time dependence is probably due to obliteration of the record of transitions by multiple substitutions at the same nucleotide site. This finding illustrates the importance of choosing closely related species for analysis of the evolutionary process. The remarkable bias toward transitions in mtDNA evolution necessitates the revision of equations that correct for multiple substitutions at the same site. With revised equations, we calculated the incidence of silent and replacement substitutions in the two protein-coding genes. The silent substitution rate is 4 to 6 times higher than the replacement rate, indicating strong functional constraints at replacement sites. Moreover, the silent rate for these two genes is about 10% per million years, a value 10 times higher than the silent rate for the nuclear genes studied so far. In addition, the mean substitution rate in the three mitochondrial tRNA genes is at least 100 times higher than in nuclear tRNA genes. Finally, genealogical analysis of the sequence differences supports the view that the human lineage branched off only slightly before the gorilla and chimpanzee lineages diverged and strengthens the hypothesis that humans are more related to gorillas and chimpanzees than is the orangutan. Peer Reviewed http://deepblue.lib.umich.edu/bitstream/2027.42/48036/1/239_2005_Article_BF01734101.pdf
A phylogenetic tree for major lineages of iguanian lizards is estimated from 1,488 aligned base positions (858 informative) of newly reported mitochondrial DNA sequences representing coding regions for eight tRNAs, ND2, and portions of ND1 and COI. Two well-supported groups are defined, the Acrodonta and the Iguanidae (sensu lato). This phylogenetic hypothesis is used to investigate evolutionary shifts in mitochondrial gene order, origin for light-strand replication, and secondary structure of tRNACys. These three characters shift together on the branch leading to acrodont lizards. Plate tectonics and the fossil record indicate that these characters changed in the Jurassic. We propose that changes to the secondary structure of tRNACys may destroy function of the origin for light-strand replication which, in turn, may facilitate shifts in gene order.
The recently-developed statistical method known as the "bootstrap" can be used to place confidence intervals on phylogenies. It involves resampling points from one's own data, with replacement, to create a series of bootstrap samples of the same size as the original data. Each of these is analyzed, and the variation among the resulting estimates taken to indicate the size of the error involved in making estimates from the original data, In the case of phylogenies, it is argued that the proper method of resampling is to keep all of the original species while sampling characters with replacement, under the assumption that the characters have been independently drawn by the systematist and have evolved independently. Majority-rule consensus trees can be used to construct a phylogeny showing all of the inferred monophyletic groups that occurred in a majority of the bootstrap samples. If a group shows up 95% of the time or more, the evidence for it is taken to be statistically significant. Existing computer programs can be used to analyze different bootstrap samples by using weights on the characters, the weight of a character being how many times it was drawn in bootstrap sampling. When all characters are perfectly compatible, as envisioned by Hennig, bootstrap sampling becomes unnecessary; the bootstrap method would show significant evidence for a group if it is defined by three or more characters.
The Vangidae, an endemic family in Madagascar, contains 14 species in 11 genera. The foraging behaviour of 13 species of vangids was investigated during the periods August-November 1989 and September-November 1990. These vangids are grouped into six bill types according to their bill shape, using the analogy of gripping tools: (1) forceps. (2) radio pliers, (3) strong pinchers, (4) pliers, (5) standard and (6) flat forceps types. We recognized seven foraging niches: (A) canopy-gleaning, (B) general, (C) ground-snatching, (D) trunk/ branch-probing, (E) leaf and twig/branch-gleaning/probing, (F) leaf and twig/branch-gleaning and (G) trunk-gleaning niches. Two or more coexisting species with the same foraging niche differed in their bill types. Those vangids that exploited similar resources segregated in their bill types, geographic ranges and/or foraging niches, presumably to avoid severe competition. Several vangid species partially occupied the ecological niche that would be filled by woodpeckers elsewhere.
The combined use of mitochondrial DNA markers and polymerase chain reaction (PCR) techniques has greatly enhanced evolutionary studies. These techniques have also promoted the discovery of mitochondrial-like sequences in the nuclear genomes of many animals. While the nuclear sequences themselves are interesting, and capable of serving as valuable molecular tools, they can also confound phylogenetic and population genetic studies. Clearly, a better understanding of these phenomena and vigilance towards misleading data are needed.
The phylogenetic affiliation of the extinct marsupial wolf (Thylacinus cynocephalus), which once was widespread in Australia, has been uncertain. On the basis of morphology, some systematists argue that the thylacine was most closely related to an extinct group of South American carnivorous marsupials, the borhyaenids, whereas others consider it to be closer to Australian carnivorous marsupials. Here we use direct sequencing by means of the polymerase chain reaction (PCR) to compare 219 bases of mitochondrial (mt) DNA from museum specimens of the marsupial wolf and representatives of six genera of extant marsupials. In agreement with the results of an antigenic study of albumin, our genetic data suggest that the marsupial wolf was more closely related to other Australian marsupial carnivores than to those of South America. Thus, the marsupial wolf represents an example of convergent morphological evolution to South American carnivorous marsupials as well as to true wolves.
The sensitivity of the commonly used progressive multiple sequence alignment method has been greatly improved for the alignment
of divergent protein sequences. Firstly, individual weights are assigned to each sequence in a partial alignment in order
to downweight near-duplicate sequences and up-weight the most divergent ones. Secondly, amino acid substitution matrices are
varied at different alignment stages according to the divergence of the sequences to be aligned. Thirdly, residue-specific
gap penalties and locally reduced gap penalties in hydrophilic regions encourage new gaps in potential loop regions rather
than regular secondary structure. Fourthly, positions in early alignments where gaps have been opened receive locally reduced
gap penalties to encourage the opening up of new gaps at these positions. These modifications are incorporated into a new
program, CLUSTAL W which is freely available.