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1.
PROCLAMATION     
Natural hybridisation in Old World buzzards (Buteo) is an uncommon phenomenon with important ecological implications. This genus constitutes an intricate radiation of genetically poorly differentiated raptors whose taxonomic classification is a frequent subject of debate. We report the first case of successful hybridisation between the African subspecies of the Long-legged Buzzard Buteo rufinus cirtensis and Common Buzzard Buteo buteo buteo in a new contact zone in the Strait of Gibraltar (southern Spain). The hybrid offspring showed mixed characters from parental species indicating that, among others, hybridisation could explain the increasing presence of phenotypically odd reddish buzzards in southern Spain and northern Morocco. Given their close phylogenetic relation and their recently reduced allopatry, an increase in the hybridisation rate, fertile descendants and genetic introgression seem to be viable. We identify the potential contact zones where genetic monitoring is needed to gain insight on the real extent of this hybridisation and its possible effects on the current climate change scenario.  相似文献   

2.
DNA sequences of the mitochondrial nd6 gene and the non-repetitive part of the pseudo-control region (PsiCR) were isolated from 101 individuals to analyze the phylogenetic relationships among all buzzards of the genus Buteo and other buteonine genera. Comparisons of the two marker sequences indicate that the PsiCR evolved two times faster than the nd6 gene. The PsiCR proved to be an efficient, neutral genetic marker sequence for phylogenetic analyses at the intrageneric level, especially suitable for analyses based on old tissues, where only short fragments can be obtained. The molecular data set implies a neotropical origin of the genus Buteo. Monophyly of the genus Buteo as currently defined is contradicted due to the positions of Asturina nitida, Geranoaetus melanoleucus, Buteo magnirostris, and Buteo leucorrhous. These findings suggest several taxonomic consequences. A. nitida and G. melanoleucus should be included into the genus Buteo. Moreover, B. leucorrhous should be transferred into the genus Percnohierax (which clusters with Parabuteo), and B. magnirostris into the genus Rupornis. According to this classification of the genus Buteo, the basal lineage of the genus is formed by a clade containing Buteo polyosoma, Buteo poecilochrous, and Buteo melanoleucus. The "woodland buteos" form a paraphyletic assemblage with B. magnirostris as a clearly separated lineage basal to the genus Buteo.  相似文献   

3.
Old World leaf-nosed bats (Hipposideridae) are among the most widespread and ecologically diverse groups of insectivorous bats in the Old World tropics. However, phylogenetic relationships in Hipposideridae are poorly resolved at both the generic and species levels, and deep genetic divergence within several Southeast Asian species suggests that current taxonomy underestimates hipposiderid diversity in this region. We used mitochondrial and nuclear sequence data to conduct the first extensive molecular phylogenetic analysis of Southeast Asian hipposiderid bats. Inclusion of multiple samples per taxon allowed testing for evidence of evolutionarily distinct lineages within taxa currently defined as single species. In contrast to earlier phylogenies based on morphometrics, molecular data support monophyly of Hipposideros, but are ambiguous regarding the monophyly of Hipposideridae. With a few exceptions, molecular data also support currently recognized species groups classified by qualitative morphological characters. Widespread paraphyly and polyphyly within many currently recognized species of Hipposideros indicates that evolutionary diversity in the genus is underrepresented by current nomenclature. Comparison of available morphological and echolocation data suggest that both geographic isolation and ecological selection have contributed to the diversification of Southeast Asian hipposiderid bats.  相似文献   

4.
Based on recent molecular phylogenetic studies, the Old World bat family Miniopteridae, composed of species in the genus Miniopterus , has been shown to contain complex paraphyletic species, many of which are cryptic based on convergent morphological characters. Herein we resolve the phylogenetic relationships and taxonomy of the species complex M . manavi on Madagascar and in the Comoro Archipelago, where these animals occur in different bioclimatic zones. First using mitochondrial cytochrome- b sequence data to define clades and then morphology to corroborate the molecular data, including comparisons to type specimens, we demonstrate that animals identified as this taxon are a minimum of three species: M . manavi sensu stricto occurs in at least the central portion of the Central Highlands; M . griveaudi has a broad distribution in lowland northern and central western Madagascar and the Comoros (Anjouan and Grande Comore), and M . aelleni sp. n. has been found in northern and western Madagascar and the Comoros (Anjouan). In each case, these three clades were genetically divergent and monophyletic and the taxa are diagnosable based on different external and craniodental characters. One aspect that helped to define the systematics of this group was isolation of DNA from one of the paratypes of M. manavi collected in 1896 and new topotypic material. Miniopterus manavi is most closely allied to a recently described species, M. petersoni . At several localities, M . griveaudi and M . aelleni have been found in strict sympatry, and together with M. manavi sensu stricto show considerable convergence in morphological characters, but are not immediate sister taxa. In defining and resolving the systematics of cryptic species, such as miniopterid bats, the process of defining clades with molecular tools, segregating the specimens accordingly, and identifying corroborative morphological characters has been notably efficient.  相似文献   

5.
The satyrine butterfly subtribe Mycalesina has undergone one of the more spectacular evolutionary radiations of butterflies in the Old World tropics. Perhaps the most phenotypically pronounced diversification of the group has occurred in the Malagasy region, where 68 currently recognized species are divided among five genera. Here, we report the results of phylogenetic analyses of sequence data from the cytochrome c oxidase II and cytochrome b mitochondrial genes, for a total of 54 mycalesine taxa, mostly from Madagascar. These molecular data complement an existing data set based on male morphological characters. The molecular results support the suggestion from morphology that three of the five Malagasy genera are paraphyletic and support the monophyly of at least three major morphological clades. Novel hypotheses of terminal taxon pairs are generated by the molecular data. Dense taxon sampling appears to be crucial for elucidating phylogenetic relationships within this large radiation. A potentially complex scenario for the origin of Malagasy mycalesines is proposed.  相似文献   

6.
Trading-off food and safety is considered a predominant component of foraging behavior. We examined whether predators' response to potential prey is state-dependent, and suggest that risk of injury while pursuing the prey affects the predators' foraging behavior in a similar manner as predation risk affects prey foraging behavior. We examined how the daring of steppe buzzards Buteo buteo vulpinus in pursuing their prey varied with body condition. We measured the time it took juvenile buzzards to attack a mouse placed in a Bal-Chatri cage trap and related it to their body condition. We found that buzzards in poorer body condition tended to hesitate less before pursuing their prey than did buzzards in better body condition. We suggest that behavioral decisions of buzzards are state-dependant and are influenced by the risk of injury involved in pursuing their prey.  相似文献   

7.
Evolution and phylogeny of old world deer   总被引:11,自引:0,他引:11  
The phylogenetic pattern and timing of the radiation of Old World deer was determined based on the complete mitochondrial cytochrome b gene from 33 Cervinae taxa. Using rooted and unrooted phylogenies derived from distinct theoretical approaches, strong support was achieved for monophyly of the Old World deer with muntjacs as sister group as well as for the divergence of at least three distinct genera: Rucervus, Dama, and Cervus. The latter clade comprises what have previously been regarded as the genera or subgenera Panolia, Rusa, Cervus, Sika, and probably Przewalskium. Our data also consistently confirmed paraphyly of nominate C. elaphus and did not support the monophyly of Axis. We used these molecular phylogenies to assess the homoplastic evolution of morphological, geographical, ecological, and selected behavioural character state differences within the Cervinae. Reliable fossil calibrations, large molecular data sets, and improved dating methods are shaping a molecular time scale for the evolutionary radiation of Old World deer that occurred at the Miocene/Pliocene transition and is largely compatible with existing palaeontological evidence. Using node ages estimated from sequence data, we estimated an average per-lineage diversification rate of 0.51+/-0.1 species per million years (my) over roughly the last 6 mya.  相似文献   

8.
Studies of phylogenetic relationships among cypresses of the Old World (Cupressus; Cupressaceae) have been plagued by unresolved relationships, poor branch support, and conflict between data sets and methods of analysis. In this study, we combined 5.4 kb of aligned DNA sequence and 157 binary characters with previously published data in examining phylogenetic relationships among Cupressus species. Bayesian and parsimony analysis of the combined data or of the nuclear data alone always recovered three principal clades of Cupressus; however, tests of phylogenetic incongruence could not distinguish between competing relationships among the three principal Cupressus lineages. In contrast, incongruence tests often found statistically significant conflict between the nuclear and plastid data, particularly with respect to the placement of C. chengiana. Consistent with previous studies and prevailing taxonomic opinion, we find C. darjeelingensis more closely related to cypresses of the New World (Hesperocyparis). In contrast, we placed accessions of C. assamica and C. tonkinensis, two putatively Old World species suggested to be misidentified New World taxa by some authors, within well-supported Old World clades. Statistical analysis of genetic distances suggests instances in which taxa recognized as distinct species by some authors are identical or nearly so and may best be considered a single taxon. Conversely, we identify instances in which infraspecific taxa are more distantly related to one another than those traditionally recognized as distinct species. Factors confounding cypress taxonomies, including poor morphological differentiation, misidentification, and the use of accessions of questionable provenance, are discussed.  相似文献   

9.
Evidence of incongruence between mitochondrial and nuclear gene trees is now becoming documented with increasing frequency. Among the Old World monkeys, this discordance has been well demonstrated in the Cercopithecinae, but has not yet been investigated in the Colobinae. The mitochondrial relationships between the colobine genera have recently been clarified and cluster Presbytis and Trachypithecus as sister taxa to the exclusion of Semnopithecus. This is incongruent with previous morphological hypotheses that suggest the latter two are sister taxa, and perhaps even congeneric. In addition to analyzing a previously published 10,896 bp mitochondrial dataset, we sequenced and analyzed a 4297 bp fragment of the X-chromosome in order to test the competing mitochondrial and morphological phylogenetic hypotheses. The results from the mitochondrial dataset again support a Presbytis+Trachypithecus group while the X-chromosomal dataset supported a Semnopithecus+Trachypithecus group. A Shimodaira-Hasegawa test performed on both datasets indicates that the mitochondrial and X-chromosomal trees are significantly better at explaining their respective datasets than alternative topologies (p<0.05). We suggest that differential lineage sorting or ancient hybridization may be the cause of this strong discordance between the mitochondrial and X-chromosomal markers in these taxa.  相似文献   

10.
Myriophora is the most species‐rich group of parasitoids that attack toxic, chemically defended millipedes in the superorder Juliformia and order Polydesmida—a resource that few insect predators and parasitoids are able to exploit. Worldwide, there are an estimated 200 species of Myriophora, with the majority of the diversity centred in the Neotropical region. The phylogeny of Myriophora is unknown, biogeographical patterns are not documented, and known host associations have not been assessed in a phylogenetic context. We provide the first phylogenetic study of the genus from a data set composed of 52 taxa primarily from the Neotropical region including 10 outgroups, 40 morphological characters, and molecular data from three mitochondrial (16S, COI and ND1) and one nuclear marker (AK). We find that Myriophora dispersed from the New World to the Old World in a single event before subsequently spreading to the Afrotropical region. The ancestral hosts reconstructed for Myriophora are the benzoquinone‐producing Juliformia, and this association has been retained in the Old World clade. In the Neotropical region, Myriophora that are associated with cyanide‐producing polydesmidan millipedes are confined to a single clade that shows remarkably little genetic variation between clearly morphologically diagnosable species.  相似文献   

11.
The subfamily Crotalinae (pitvipers) contains over 190 species of venomous snakes distributed in both the Old and New World. We incorporated an extensive sampling of taxa (including 28 of 29 genera), and sequences of four mitochondrial gene fragments (2.3kb) per individual, to estimate the phylogeny of pitvipers based on maximum parsimony and Bayesian phylogenetic methods. Our Bayesian analyses incorporated complex mixed models of nucleotide evolution that allocated independent models to various partitions of the dataset within combined analyses. We compared results of unpartitioned versus partitioned Bayesian analyses to investigate how much unpartitioned (versus partitioned) models were forced to compromise estimates of model parameters, and whether complex models substantially alter phylogenetic conclusions to the extent that they appear to extract more phylogenetic signal than simple models. Our results indicate that complex models do extract more phylogenetic signal from the data. We also address how differences in phylogenetic results (e.g., bipartition posterior probabilities) obtained from simple versus complex models may be interpreted in terms of relative credibility. Our estimates of pitviper phylogeny suggest that nearly all recently proposed generic reallocations appear valid, although certain Old and New World genera (Ovophis, Trimeresurus, and Bothrops) remain poly- or paraphyletic and require further taxonomic revision. While a majority of nodes were resolved, we could not confidently estimate the basal relationships among New World genera and which lineage of Old World species is most closely related to this New World group.  相似文献   

12.
To test three hypotheses accounting for bipolar distributions in Engraulis , seven of eight taxa (except E. eurystole ) were surveyed with allozymes (34 loci) and 521 bp of the mitochondrial DNA cytochrome b gene. Both allozymes and mtDNA sequences revealed deep separations between New World and Old World anchovies with a mean allozyme genetic distance D  = 1·26 and net mtDNA sequence divergence d  = 15%. These values reflected separations of 5 to 10 million years. Contrary to previous phylogenetic hypotheses, which place north‐east Pacific E. mordax and south‐east Pacific E. ringens as sister taxa, the south‐west Atlantic E. anchoita and E. ringens are most closely related to each other. The north‐east Pacific E. mordax is the closest lineage to the Old World Engraulis , a group of taxa showing low divergences typical of population‐level separations (mean D  = 0·06; mean d  = 0·87%). Bipolarities of sister taxa in the east Atlantic and west Pacific reflect recent dispersals. Bipolarities in the east Pacific and west Atlantic represent paraphyletic taxa in lineages isolated since the Miocene. None of the bipolarities can be attributed to tectonic separations or competitive displacements from the tropics, but the latter situation should be re‐evaluated with comparisons to tropical anchovies of the New World.  相似文献   

13.
A mobile element based phylogeny of Old World monkeys   总被引:6,自引:0,他引:6  
SINEs (Short INterspersed Elements) are a class of non-autonomous mobile elements that are <500 bp in length and have no open reading frames. Individual SINE elements are essentially homoplasy free with known ancestral states, making them useful genetic systems for phylogenetic studies. Alu elements are the most successful SINE in primate genomes and have been utilized for resolving primate phylogenetic relationships and human population genetics. However, no Alu based phylogenetic analysis has yet been performed to resolve relationships among Old World monkeys. Using both a computational approach and polymerase chain reaction display methodology, we identified 285 new Alu insertions from sixteen Old World monkey taxa that were informative at various levels of catarrhine phylogeny. We have utilized these elements along with 12 previously reported loci to construct a phylogenetic tree of the selected taxa. Relationships among all major clades are in general agreement with other molecular and morphological data sets but have stronger statistical support.  相似文献   

14.
Evolutionary relationships within Astragalus L. (Fabaceae) were inferred from nucleotide sequence variation in nuclear ribosomal DNA of both New World and Old World species. The internal transcribed spacer regions (ITS) of 18S–26S nuclear ribosomal DNA from representatives of 26 species of Astragalus, three species of Oxytropis DC., and two outgroup taxa were analyzed by polymerase chain reaction amplification and direct DNA sequencing. The length of the ITS 1 region within these taxa varied from 221 to 231 bp, while ITS 2 varied in length from 207 to 217 bp. Of the aligned, unambiguous positions, approximately 34% were variable in each spacer region. In pairwise comparisons among Astragalus species and outgroup taxa, sequence divergence at these sites ranged from 0 to 18.8% in ITS 1 and from 0 to 21.7% in ITS 2. Parsimony analyses of these sequences resulted in a well-resolved phylogeny that is highly concordant with previous cytogenetic and chloroplast DNA evidence for a major phylogenetic division in the genus. These data suggest that the New World aneuploid species of Astragalus form a monophyletic but morphologically cryptic group derived from euploid species of Old World (Eurasian) origin, which are consequently paraphyletic.  相似文献   

15.
Capparis (Capparaceae) has been used as a medicinal plant since ancient time. Capparis species were divided into Old World and New World taxa as described by the sectional division of Capparis. However, plastid DNA sequence data of Indian Capparis species were not analyzed in previous phylogenetic studies. Here, we have added Indian Capparis data in previous phylogeny and analyzed the relationship of Indian Capparis with Old World and New World taxa. The plastid phylogeny presented here includes Capparis taxa from its major distribution areas, New World and African capparoids. The presented phylogeny is used for the determination of biogeographic history of Capparis and recently segregated genera. Phylogenetic analyses of the combined plastid data revealed that the Indian Capparis are more closely related to Old World taxa and have connections with African, Australian and Eastern Asian species. Sectional classification of Old World and Indian Capparis considered in this study is reflected from the presented plastid phylogeny. The ancestral area reconstruction using Bayesian Binary Markov Chain Monte Carlo method strongly supports for the Africa as the ancestral region for both Old World and New World Capparis. Molecular marker-based genetic diversity studies on Indian Capparis are scarce. This work also includes the genetic diversity study of Indian Capparis species. Utility and efficacy of ISSR markers to study inter- and intraspecies variation in Capparis is evident from the AMOVA results.  相似文献   

16.
Molecular and biochemical genetic analyses have revealed that many marine invertebrate taxa, including some well-studied and presumably cosmopolitan species, are actually complexes of sibling species. When morphological differences are slight and estimated divergence times are old, data suggest either unusually high rates of sequence evolution or long-term morphological stasis. Here, five gene regions (mitochondrial cytochrome oxidase subunit I and large-subunit ribosomal 16S rDNA and nuclear ITS1, 5.8S rDNA, and ITS2) were analyzed in four geographic samples of the meiobenthic harpacticoid copepod Cletocamptus deitersi. Molecular sequences revealed four extremely differentiated molecular lineages with unalignable nuclear intergenic spacers and mitochondrial uncorrected divergences reaching 25% (cytochrome oxidase) and 36% (16S rDNA). These levels of divergence are greater than those reported previously for congeneric species in diverse invertebrate taxa, including crustaceans. The nominally intraspecific divergence matches or exceeds the corresponding divergence from a known congener (Cletocamptus helobius). A molecular clock applied to the cytochrome oxidase subunit I data suggests that these lineages split in the Miocene, consistent with the fossil record of a North American Cletocamptus from the same period. Morphological differences among the major lineages are subtle but congruent with the patterns of genetic differentiation. Our conclusion, based on concordant patterns of variation in two mitochondrial and three nuclear gene regions, as well as morphological observations, is that C. deitersi in North America is composed of at least four separate species by the genealogical concordance, phylogenetic, and morphological-species criteria. Alternative explanations for the deep phylogenetic nodes and apparent morphological stasis, including high rates of sequence evolution, balancing selection, and genetic signatures of historical events, are considered unlikely.  相似文献   

17.
A partial sequence of the cytb gene (382 bp) was amplified and sequenced from 35 individuals (mainly museum specimens) of the genus Pernis representing all valid taxa (10) and two taxa (P. p. gurneyi, P. p. japonicus) with questionable validity as well as representatives of the Old World Perninae, namely Henicopernis and Aviceda, to assess their relationships to the genus Pernis. Furthermore, Gypaetus barbatus, Neophron percnopterus, and Buteo buteo were included as outgroup taxa. In the trees derived from the sequence data, Aviceda represents the sister group of the genus Pernis. The genus Henicopernis and the Old World vultures Gypaetus andNeophron appear rather distantly related to Pernis. Within the genus Pernis, two of the described species (Pernis apivorus, Pernis ptilorhyncus) form monophyletic groups, whereas the relationships of the two clades representing three subspecies of Pernis celebensis are still uncertain. Although this study is based on comparatively short DNA‐sections, the trees deduced from these sequences can be considered as a first approach for inferring the phylogenetic relationships of the genus Pernis and related genera and for addressing questions concerning the evolutionary history, biogeography, and systematics of this group.  相似文献   

18.
19.
This contribution provides an insight into Atheriniformes systematics based on four mitochondrial regions: 12S rRNA, cytb, COI and control region (2794bp in total). In the Atherinopsoidei (New World silversides), comparisons among five species of Odontesthes, O. argentinensis, O. bonariensis, O. smitti, O. hatcheri and O. incisa revealed a putative marine-freshwater pairing pattern of Odontesthes species, possibly driven by sea level fluctuations of South American waters. This study represents the first data on molecular phylogeny of Odontesthes species that can be of usefulness to biodiversity conservation policies. In the Atherinoidei (Old World silversides), Atherina boyeri was corroborated as a species complex constituted by a marine form, a marine with dark spots form and a brackish form. Concretely, Odontesthes and Atherina may represent geographically replicated models to study genetic adaptation and speciation of marine species to brackish and freshwater habitats. In addition, phylogenetic analyses supported Odontesthes and Atherina as monophyletic taxa and their separation into two differentiated suborders Atherinopsoidei and Atherinoidei, respectively.  相似文献   

20.
What actually is the expected pattern relating to molecular and morphological divergence? A phylogenetic correlation is expected; however, natural selection may force morphological evolution away from this expected correlation. To assess this relationship and the way it is modulated by selection, we investigated the radiation of the murine rodents, also called as Old World rats and mice. Regarding their diet, they are diversified as they include many omnivorous as well as specialist taxa. The size and shape of the mandible, a morphological character involved in the feeding process, was quantified and compared with an estimate of molecular divergence based on interphotoreceptor retinoid binding protein (IRBP) sequences. Size and shape of the mandible appeared to be related by an allometric relationship whatever the ecology of the taxa. Small size characterizes most murines, causing a dominance of low size distances; still, the frequency of important size differentiation increases with molecular distances. Regarding shape changes, the pattern is much contrasted between omnivores and specialists. A pattern of phenotypic drift characterizes the mandible evolution of taxa sharing an omnivorous diet. Little saturation occurs over more than 10 million years with regard to the shape of the mandible that appears as a valuable marker of phylogenetic history in this context. In contrast, important morphological distances can occur when specialist taxa are involved, even when the molecular divergence is small. Ecological specialization thus triggers an uncoupling of molecular and phenotypic evolution, and the departure from a phenotypic drift pattern.  相似文献   

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