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1.
This study presents a detailed phylogeographical analysis of one of the most conspicuous groups of lizards in northwestern Patagonia, the Liolaemus kriegi complex. This region is geographically very complex as a result of Andean orogeny and subsequent volcanism coupled with a long history of glaciations and climatic changes. For 247 individuals we sequenced one mitochondrial gene (cytochrome b) and for a subset we sequenced another mitochondrial gene [12S ribosomal RNA (12S)] and two nuclear fragments [kinesin family member 24 (KIF24) and BA3 ribosomal RNA (BA3)]. We obtained gene trees and mitochondrial and nuclear haploytpe networks, and estimated genetic distances between the main lineages and basic molecular diversity indices. We also performed spatial analysis of molecular variance (SAMOVA) and Bayesian Skyline Plot (BSP) analyses, and concordant patterns from different lines of evidence permitted delimitation of seven lineages: two described species, Liolaemus buergeri and Liolaemus tregenzai; four candidate species, Liolaemus sp. A, Liolaemus sp. B, Liolaemus sp. C, and Liolaemus sp. D; and one lineage that includes all individuals from the geographical range of Liolaemus ceii and L. kriegi, referred to as L. kriegi + L. ceii. We discuss the evolutionary processes that may contribute to the origin of these lineages and their taxonomic and conservation implications. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 256–269.  相似文献   

2.
In this study, we used a recently developed supertrees method to test for shared phylogeographical signal in partially overlapping geographical ranges of lizards of the genus Liolaemus from the Andean Range in south-central Chile. We reconstruct mtDNA gene trees for three partially codistributed species ( Liolaemus tenuis, L. lemniscatus and L. pictus ), and our sampling effort is sufficient to allow statistical tests of shared signal between the combinations L. tenuis–L. pictus , and L. tenuis–L. lemniscatus . For both combinations, standardized maximum agreement subtrees scores showed statistically significant signal for shared pattern in regions of overlap, as evaluated by randomization tests ( P <  0.001 and < 0.05, respectively). The matrix representation with parsimony tree obtained from the combination of the three different gene trees revealed concordant phylogeographical associations of all species, and was consistent with the geographical association of intraspecific haploclades with three Chilean bioclimatic zones. A multidimensional scaling analysis of several climate variables showed highly significant differences among these zones, which further suggests that they may have contributed to similar patterns of intraspecific divergence across all three species. In the mesomorphic zone in Central Chile, the species L. tenuis and L. lemniscatus may have codiverged in response to shared orogenic vicariant events, which likely predominated over climatic events associated with cycles of glacial advance and retreat. In the hygromorphic zone in southern Chile, however, glacial cycles likely predominated in structuring the phylogeographical histories of L. tenuis and L. pictus , although important ecological differences between these two caution against broad generalizations at this point.  相似文献   

3.
4.
In this study, we present a phylogeographic analysis of a group of lizards distributed in north‐western Patagonia, the Liolaemus elongatus complex. We sequenced 581 individuals for one mitochondrial gene (cytochrome‐b), and for a subset, we sequenced another mitochondrial gene (12S rRNA) and two nuclear genes: kinesin family member 24 (KIF24) and the anonymous nuclear locus LDAB1D. We estimated gene trees, mitochondrial and nuclear haploytpe networks, standard molecular diversity indices, genetic distances between lineages and Bayesian skyline plots. Our results provide evidence for recognition of seven species previously described within the L. elongatus complex: Liolaemus antumalguen, Liolaemus chillanensis, Liolaemus carlosgarini, Liolaemus burmeisteri, Liolaemus smaug, Liolaemus elongatus and Liolaemus crandalli, but we did not find sufficient evidence to support Liolaemus choique, Liolaemus shitan or Liolaemus sp. 6 as distinct species. We identified four candidate species (Liolaemus sp. 1, Liolaemus sp. 2, Liolaemus sp. 3 and Liolaemus sp. 7), and we discuss evolutionary processes that may have contributed to the origin of these lineages and their taxonomic and conservation implications.  相似文献   

5.
In poorly known groups for which data are insufficient to develop biologically plausible model‐based approaches to phylogeographical analyses, a ‘first hypotheses’ protocol is suggested as offering the best way to generate hypotheses for subsequent model‐based tests. Preliminary hypotheses are formulated about species boundaries and population processes in three species complexes of the Liolaemus boulengeri group in the context of mtDNA ‘congeneric phylogeography’. The temperate South American Liolaemus provides a model with ancient and recent allopatric divergence across ecologically and geologically complex landscapes, incipient speciation, secondary contact, and discordance between molecular and morphological patterns of variation. Moderately dense sampling of widely distributed ‘inertial’ species in the Patagonian Steppe has revealed hidden genetic and probably species diversity, and also hinted at demographic and historical processes that may have shaped the histories of these taxa. Five of the seven focal species of the present study were paraphyletic for mtDNA genealogies, suggesting that they represent complexes of species, and nested clade phylogeographical analysis (NCPA) analyses suggest that different historical and demographic processes have shaped the observed patterns. Introgression and incomplete lineage sorting are hypothesized as being the cause of some of the observed paraphyly. Provisional delimitations of species are proposed and NCPA is used to generate hypotheses of population history, all of which are subject to further testing. Multi‐faceted studies, involving phylogenetic assessments of independent molecular markers and morphological variation across codistributed taxa with estimates of niche breadths in a landscape context, will likely yield the most promising returns for cross‐validation of hypotheses of population and speciation histories. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 89 , 241–275.  相似文献   

6.
The temperate South American lizard genus Liolaemus is the one of the most widely distributed and species‐rich genera of lizards on earth. The genus is divided into two subgenera, Liolaemus sensu stricto (the ‘Chilean group’) and Eulaemus (the ‘Argentino group’), a division that is supported by recent molecular and morphological data. Owing to a lack of reliable fossil data, previous studies have been forced to use either global molecular clocks, a standardized mutation rate adopted from previous studies, or the use of geological events as calibration points. However, simulations indicate that these types of assumptions may result in less accurate estimates of divergence times when clock‐like models or mutation rates are violated. We used a multilocus data set combined with a newly described fossil to provide the first calibrated phylogeny for the crown groups of the clade Eulaemus, and derive new fossil‐calibrated substitution rates (with error) of both nuclear and mtDNA gene regions for Eulaemus specifically. Divergence date estimates for each of the crown groups and appropriate rate estimates will provide the foundation for understanding rates of speciation, historical biogeography, and phylogeographical history for various clades in one of the most diverse lizard genera in the poorly studied Patagonian region. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 825–835.  相似文献   

7.
Abstract Invasive species have been hypothesized to out‐compete natives though either a Jack‐of‐all‐trades strategy, where they are able to utilize resources effectively in unfavourable environments, a master‐of‐some, where resource utilization is greater than its competitors in favourable environments, or a combination of the two (Jack‐and‐master). We examined the invasive strategy of Berberis darwinii in New Zealand compared with four co‐occurring native species by examining germination, seedling survival, photosynthetic characteristics and water‐use efficiency of adult plants, in sun and shade environments. Berberis darwinii seeds germinated more in shady sites than the other natives, but survival was low. In contrast, while germination of B. darwinii was the same as the native species in sunny sites, seedling survival after 18 months was nearly twice that of the all native species. The maximum photosynthetic rate of B. darwinii was nearly double that of all native species in the sun, but was similar among all species in the shade. Other photosynthetic traits (quantum yield and stomatal conductance) did not generally differ between B. darwinii and the native species, regardless of light environment. Berberis darwinii had more positive values of δ13C than the four native species, suggesting that it gains more carbon per unit water transpired than the competing native species. These results suggest that the invasion success of B. darwinii may be partially explained by combination of a Jack‐of‐all‐trades scenario of widespread germination with a master‐of‐some scenario through its ability to photosynthesize at higher rates in the sun and, hence, gain a rapid height and biomass advantage over native species in favourable environments.  相似文献   

8.
In the current study, we review the taxonomic status of Liolaemus nigromaculatus. Despite being the nominal species of the nigromaculatus group and being the second species of the genus Liolaemus that was described, this species is of uncertain type locality and its true identification is a matter of discussion. After carefully analyzing several digital pictures of the holotype (juvenile male), reviewing all of the literature concerning the issue, examining specimens of nearly all recognized species of the nigromaculatus group, and determining the locations visited by the specimen collector, we are able to point out the following: 1) Liolaemus nigromaculatus was collected between Puerto Viejo and Copiapó of the Atacama region in Chile, and not in Huasco 2) Liolaemus bisignatus is a nomen nudum, and populations attributed to Liolaemus bisignatus should be referred to as Liolaemus nigromaculatus. 3) There is agreement that Liolaemus copiapoensis is indistinguishable from populations currently referred to as Liolaemus bisignatus (= Liolaemus nigromaculatus), 4) Populations found in Huasco (currently considered the type locality of Liolaemus nigromaculatus) are very similar to those found in Caldera (currently considered Liolaemus bisignatus) and should be designated as Liolaemus nigromaculatus, and 5) Liolaemus oxycephalus and Liolaemus inconspicuus are not synonymous with Liolaemus nigromaculatus, although their true identities are difficult to determine. We also detail several characteristic based on the holotype of Liolaemus nigromaculatus, in addition to drawing diagnostic comparisons between this species and others belonging to the nigromaculatus group.  相似文献   

9.
A procedure in which combined molecular phylogeographical analyses among populations of Hemerocallis middendorfii (Hemerocallidaceae, Asparagales) were applied allowed comparisons to be made with the geological history. Information on geographical areas in which synapomorphic mutations occurred was used in molecular phylogeographical analyses for the first time in this study, in addition to molecular maximum-parsimonious analyses and TCS analyses. Nucleotide sequences of the intergenic region between the rbcL and atpB genes and the trnL (UAA) intron in chloroplast DNA were analyzed for 28 Japanese and three Chinese populations of H. middendorfii, 10 populations of closely related species and four outgroup species. The data of the three analyses in general agreed with one another and indicated that the separation of this species had proceeded in conjunction with the geological vicariance or orogeny. Where the synapomorphic mutations occurred, three patterns were recognized. They correlated with the geological history, namely, the age when the Japanese Archipelago and the Continent had joined, when the Sea of Japan was formed, and when there was separation from the Continent and the formation of each of the islands in the Japanese Archipelago. It was suggested that ancestors of H. middendorfii originated at latest 25 million years ago when the Japanese Archipelago and the Continent had joined; that is, before the formation of the Sea of Japan.We are greatly obliged to three anonymous reviewers for their constructive comments.  相似文献   

10.
Summary Ecological species replacement of Liolaemus platei by Liolaemus lemniscatus appears to occur along a north-south oriented herb density gradient. Both congeners are the only ground-dwelling lizards in the area; this suggests that L. lemniscatus is an ecological counterpart of L. platei in herbaceous habitats. Relatively longer legs appear to be associated with the utilization of herb-free habitats by L. platei; the shorter legs possessed by L. lemniscatus are associated with the utilization of habitats of higher herb density. Morphological evidence indicates the presence of intermediate populations in the zone of intermediate herb density. Alternatives of a single-species cline versus interspecific hybridization between the two taxa are discussed.  相似文献   

11.
Species level taxonomy and phylogeographical distribution patterns in the freshwater rhodophyte Sirodotia are resolved through phylogenetic inferences based on rbcL and cox2–3 sequence data. Previous studies focused on the taxonomy of specific Sirodotia species or the distributions across a limited geographical region. Our molecular phylogenies included samples attributable to five recognized Sirodotia species and include collections from Australia, Brazil, Costa Rica, Canada, Finland, Mexico, New Zealand, South Africa and the United States. Both rbcL and cox2–3 phylogenies inferred S. suecica, S. tenuissima and S. goebelii as a monophyletic group with little sequence divergence. This result supports the synonymy of S. tenuissima and S. goebelii with S. suecica (the species name with priority). Within this clade, samples collected from Australia and New Zealand formed a monophyletic group with no other discernible phylogeographical patterns within S. suecica. This result seems to be somewhat unusual in the Batrachospermales, as other species have shown greater genetic variation among geographically distant locations. As in previous studies, S. huillensis and S. delicatula were inferred as a separate species based on the rbcL phylogeny, supporting the current taxonomy. A specimen of S. aff. huillensis from South Africa, may represent a new species but further research is necessary before it can be designated as such.  相似文献   

12.
Cannibalism is a recurrent behavior across the animal kingdom, with important ecological and evolutionary consequences due to its potential trade-offs on the fitness of involved individuals and demography dynamics. Cannibalism has been reported in eight species of several phylogenetic lineages within Liolaemus, a highly diverse genus of Neotropical lizards. Within the Liolaemus montanus series, two species are reported to eat juveniles in captivity. We observed a female Liolaemus orientalis, another L. montanus series member, which had ingested a juvenile of its own species in the wild. As it generally happens with other lizards, cannibalism in Liolaemus has been suggested to be performed by the larger sex, with L. chiliensis being the only other case observed until now in which the cannibalistic individual was a female. The fact that females are slightly smaller than males in L. orientalis means that our observation is an exception to previously observed trends. We suggest that there is a relationship between this behavior and the presence of a masculine trait in the cannibalistic female: developed precloacal pores. We also discuss how refuge availability may influence demography and the probability of dispersing juveniles encountering adults, increasing the chances for cannibalism to play some role in population density regulation.  相似文献   

13.
Viviparity is a remarkable feature in squamate sauropsids and it has evolved multiple times in parallel with the formation of a placenta. One example of this repeated evolution of viviparity and placentation occurs in the species‐rich South American genus Liolaemus with at least six independent origins of viviparity. However, evolutionary studies of placentation in this genus are limited by a lack of data on placental morphology. The aim of this study is to describe and compare the microanatomy and vessel diameter (Dv, a function of blood flow) of the placenta using scanning electron microscopy (SEM) and confocal laser scanning microscopy (cLSM) in two sympatric Andean viviparous but highly divergent species, Liolaemus robustus and Liolaemus walkeri. We found interspecific differences in cell types in the chorion, allantois, and omphalopleure that may be explained by divergent phylogenetic history. Time elapsed since divergence may also explain the pronounced interspecific differences in vessel diameter, and within each species, there are strong differences in Dv between tissue locations. Both species show features to improve gas exchange in the chorioallantoic placenta including absence of eggshell, large Dv in the allantois (L. robustus) or embryonic side of the uterus (L. walkeri), and when present, microvillous cells in the allantois (L. walkeri). Both species also show features that suggest transfer of nutrients or water in the omphaloplacenta, including an almost complete reduction of the eggshell, secretive material (L. robustus), or vesicles (L. walkeri) on cell surface uterus, and when present specialized cells in the omphalopleure (L. walkeri). No statistical differences in Dv were found among stages 32–39 in each species, suggesting that a different mechanism, other than enhanced blood flow, might satisfy the increased oxygen demand of the developing embryos in the hypoxic environments of the high Andes. J. Morphol. 276:1205–1217, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

14.
Summary The Iguanid lizard Liolaemus tenuis is shown to be a rock and trunk dweller (apparently preferring perches between 0–30 cm height) in a central Chilean locality where it coexists with a single ground-dwelling congener. In its southern distributional ranges L. tenuis is sympatric with another tree-dweller, L. pictus. Habitat shift is demonstrated in this latter case by L. tenuis concentrating on tree trunks, and at modal heights 30–60 cm. Liolaemus pictus occupies lower (apparently more favorable) perches, actively interferring with its congener.  相似文献   

15.
Dincă V  Dapporto L  Vila R 《Molecular ecology》2011,20(18):3921-3935
Widespread species have the potential to reveal large‐scale biogeographical patterns, as well as responses to environmental changes possibly unique to habitat generalists. This study presents a continental‐scale phylogeographical analysis of Polyommatus icarus, one of the most common Palaearctic butterflies, and the morphologically and ecologically similar Polyommatus celina, a recently discovered cryptic species. By combining data from mitochondrial [cytochrome c oxidase subunit I (COI)] and nuclear [internal transcribed spacer (ITS2)] molecular markers with geometric morphometrics, we document a complex phylogeographical history for the two species. Despite morphological similarities, the genetic divergence between these two species is high (more than 5% at COI) and they are not sister species. For the first time, we show that P. celina occurs not only in North Africa but also in Europe, where it inhabits several west Mediterranean islands, as well as large parts of Iberia, where it occurs in parapatry with P. icarus. The two species appear to completely exclude each other on islands, but we provide morphological and molecular evidence that introgression occurred in the Iberian Peninsula. We discovered strongly diverged lineages that seem to represent relict populations produced by past range expansions and contractions: Crete and Iberian isolates for P. icarus, Balearics–Sardinia and Sicily–Lipari for P. celina. This study shows that a combined genetic‐morphometric approach can shed light on cryptic diversity while providing the necessary resolution to reconstruct a fine‐scale phylogeographical history of species at both spatial and temporal levels.  相似文献   

16.
The world's richest mangrove‐restricted avifauna is in Australia and New Guinea. The history of differentiation of the species involved and their patterns of intraspecific genetic variation remain poorly known. Here, we use sequence data derived from two mitochondrial protein‐coding genes to study the evolutionary history of eight co‐distributed mangrove‐restricted and mangrove‐associated birds from the Australian part of this region. Utilizing a comparative phylogeographical framework, we observed that the study species present concordantly located phylogeographical breaks across their shared geographical distribution, a plausible signature of common mechanisms of vicariance underlying this pattern. Barriers such as the Canning Gap, Bonaparte Gap, and the Carpentarian Gaps all had important but varying degrees of impact on the studied species. The Burdekin Gap along Australia's eastern seaboard probably had only a minor influence as a barrier to gene flow in mangrove birds. Statistical phylogeographical simulations were able to discriminate among alternative scenarios involving six different geographical and temporal population separations. Species exhibiting recent colonizations into mangroves include Rhipidura phasiana, Myiagra ruficollis, and Myzomela erythrocephala. By contrast, Peneoenanthe pulverulenta, Pachycephala melanura, Pachycephala lanioides, Zosterops luteus, and Colluricincla megarhyncha all had deeper histories, reflected as more marked phylogeographical divisions separating populations on the eastern seaboard/Cape York Peninsula from more western regions such as the Arnhem Land, the Pilbara, and the Kimberley. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 574–598.  相似文献   

17.
Summary Two central Chile lizards differ in their response to the approach of potential predators: Liolaemus lemniscatus escapes from rocky patches into grassy patches, and Liolaemus fuscus runs away from a rock onto another within the same rocky patch. These escaping responses are associated with concealing coloration and comparatively shorter legs in L. lemniscatus, as compared to L. fuscus. The adequacy of the behavior of L. lemniscatus is discussed.  相似文献   

18.
Whether or not species participating in specialized and obligate interactions display similar and simultaneous demographic variations at the intraspecific level remains an open question in phylogeography. In the present study, we used the mutualistic nursery pollination occurring between the European globeflower Trollius europaeus and its specialized pollinators in the genus Chiastocheta as a case study. Explicitly, we investigated if the phylogeographies of the pollinating flies are significantly different from the expectation under a scenario of plant–insect congruence. Based on a large‐scale sampling, we first used mitochondrial data to infer the phylogeographical histories of each fly species. Then, we defined phylogeographical scenarios of congruence with the plant history, and used maximum likelihood and Bayesian approaches to test for plant–insect phylogeographical congruence for the three Chiastocheta species. We show that the phylogeographical histories of the three fly species differ. Only Chiastocheta lophota and Chiastocheta dentifera display strong spatial genetic structures, which do not appear to be statistically different from those expected under scenarios of phylogeographical congruence with the plant. The results of the present study indicate that the fly species responded in independent and different ways to shared evolutionary forces, displaying varying levels of congruence with the plant genetic structure. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 1021–1035.  相似文献   

19.
The lizard genus Liolaemus includes numerous constituent clusters of putatively related taxa, one of which is the Liolaemus boulengeri group, which in turn includes the sand lizards (of the Liolaemus wiegmannii subgroup). Members of the sand lizard group exhibit three different modes of burying into sand. The general morphology of the forelimb muscles of those Liolaemus species is analysed. Herein, we present a study of the forelimb musculature of all species considered by Halloy et al. (1998). This study has three principal goals. First, we are seeking myological characters that will be useful in formulating phylogenetic hypothesis about the species of Liolaemus. With these characters, we also wish to compile morphological data that represent the morphological space implied in the diverse locomotor behaviours of these animals. Second, we are looking for derived features that reflect functional changes in the use of forelimb. Third, we wish to provide a cladistic analysis that can be used to test phylogenetic hypothesis derived from other sources of data. We present 48 characters in a data set and analyse it cladistically. We obtained a hypothesis of relationships of the Liolaemus species and compared this with previous hypotheses based on other characters. The trees obtained are not congruent with previously proposed phylogenies. We were unable to identify in our trees nodes that are based on structures reflecting functional changes in the use of the forelimb. The morphological similarities in the forelimb musculature of all species analysed seems to conform a very conservative general anatomical pattern with which Liolaemus sand lizards perform most of their locomotor behaviours.  相似文献   

20.
We conducted a phylogeographical and niche modelling study of the tree Ficus bonijesulapensis, endemic to Brazilian seasonally dry tropical forests (SDTFs), in order to evaluate the effects of Quaternary climatic fluctuations on population dynamics. The trnQ–5′rps16 region of plastid DNA was sequenced from 15 populations. Three phylogeographical groups were identified by the median‐joining algorithm network and spatial analysis of molecular variance (SAMOVA) (FCT = 0.591): a central‐west, a central‐east and a scattered group. The central groups had higher total haplotype and nucleotide diversities than the scattered group. Ecological niche modelling suggested that, since the Last Interglacial (130 kyr bp ), the central and north regions have been relatively stable, whereas the southern region of the species distribution has been less stable. The phylogeographical groups showed concordance with the floristic units described for SDTFs. The low genetic diversity, unimodal mismatch distribution and unfavourable climatic conditions in the southern region suggest a recent southward expansion of the range of the species during the Holocene, supporting the hypothesis of the southward expansion of SDTFs during this period. The central and northern regions of the current distribution of F. bonijesulapensis, which are consistent with arboreal caatinga and rock outcrop floristic units, were potential refugia during Quaternary climatic fluctuations. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 189–201.  相似文献   

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