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1.
海桑科的系统进化及地理分布   总被引:4,自引:0,他引:4  
王瑞江  陈忠毅 《广西植物》2002,22(3):214-219
对海桑科植物的系统学进行了分析 ,并对海桑属的两个组进行了修订 ,即以柱头头状为主要特征的海桑组和柱头蘑菇状为主要特征的无瓣海桑组。结合海桑科海桑属植物的古孢粉学、细胞学以及古气候等资料 ,可以推论出海桑科植物的起源时间为早始新世 ,起源地点为特提斯海岸 ,3条可能的主要扩散途径是从起源中心向南沿着岛屿扩散到澳大利亚 ,向西扩散经过印度扩散至非洲 ,向北沿着海岸向日本散布。第四纪的冰川作用对海桑科植物的现代分布产生了重要的影响  相似文献   

2.
Aim Lionfish (Pterois volitans and P. miles) are popular ornamental fishes native to the Indo‐Pacific that were introduced into Florida waters and are rapidly spreading and establishing throughout the Western Atlantic (WA). Although unfortunate, this invasion provides an excellent system in which to test hypotheses on conservation biology and marine biogeography. The goals of this study are: (1) to document the geographical extent of P. volitans and P. miles; (2) to determine whether the progression of the lionfish invasion is the result of expansion following the initial introduction event or the consequence of multiple introductions at various WA locations; and (3) to analyse the chronology of the invasion in conjunction with the genetic data in order to provide real‐time assessments of hypotheses of marine biogeography. Location The Greater Caribbean, including the US east coast, Bermuda, the Bahamas and the Caribbean Sea. Methods Mitochondrial control region sequences were obtained from lionfish individuals collected from Bermuda and three Caribbean locations and analysed in conjunction with previously published data from five native and two non‐native locations (US east coast and the Bahamas; a total of six WA locations). Genetic variation within and among groups was quantified, and population structure inferred via spatial analyses of molecular variance, pairwise ΦST, exact tests, Mantel tests and haplotype networks. Results Mitochondrial DNA screening of WA lionfish shows that while P. miles is restricted to the northernmost locations (Bermuda and the US east coast), P. volitans is ubiquitous and much more abundant. Invasive populations of P. miles and P. volitans have significantly lower levels of genetic diversity relative to their native counterparts, confirming that their introduction resulted in a strong founder effect. Despite the relative genetic homogeneity across the six WA locations, population structure analyses of P. volitans indicate significant differentiation between the northern (US east coast, the Bahamas and Bermuda) and the Caribbean populations. Main conclusions Our findings suggest that the ubiquity of WA lionfish is the result of dispersal from a single source of introduction in Florida and not of multiple independent introductions across the range. In addition, the progression of the lionfish invasion (as documented from sightings), integrated with the genetic evidence, provides support for five of six major scenarios of connectivity and phylogeographical breaks previously inferred for Caribbean organisms.  相似文献   

3.
Alan Graham 《Brittonia》2003,55(4):357-383
An understanding of the phytogeographic history of a region depends upon an adequate fossil record to reveal migrational histories and the timing and directions(s) of introductions and extinctions, and to augment or circumvent undue reliance on molecular clocks. It further depends upon an accurate phylogeny of the taxa to establish real patterns of geographic affinities (phylogeography), and a relatively detailed geologic history to assess the relative roles of dispersal and vicariance in populating the islands. For the Greater Antilles new information is slowly emerging on the plant fossil record through study of new floras such as the Eocene Saramaguacán palynoflora from Cuba, and more is potentially available from the middle Oligocene San Sebastian megafossil flora of Puerto Rico that has not been revised since the early 1900s. Phylogeographic studies and area cladograms are still meager for plants, but data from various animal groups are providing a context for the general biotic history of the Antilles. Perhaps the area of greatest advance is being made in achieving an adequate plate tectonic model for the Caribbean region. There is now some convergence toward a mobilist model that depicts a Cretaceous volcanic island arc that extended from the Mexico/Chortis block in the north to Ecuador in the south, and gradually moved through the developing portal between North and South America to collide with the Bahamas Platform in the middle Eocene. Throughout this 70-million-year history there was an immensely complex pattern of collision/separation and submergence/emergence that provided opportunity both for vicariance and dispersal in the migration, evolution, and speciation of the flora of the Greater Antilles.  相似文献   

4.
5.
Aim To compare the evolutionary and ecological patterns of two extensively studied island biotas with differing geological histories (the Hawaiian Islands and the Greater Antilles). We evaluated the results from PACT (phylogenetic analysis for comparing trees), an innovative approach that has been proposed to reveal general patterns of biotic expansion (between regions) and in situ (within a region) diversification, as well as species–area relationships (SAR) and the taxon pulse dynamic. Location The Hawaiian Islands and Greater Antilles. Methods We used the PACT algorithm to construct general area cladograms and identified biotic expansion and in situ nodes. We analysed the power‐law SAR and relative contribution of biotic expansion and in situ diversification events using power‐law and linear regression analyses. Results Both biotic expansion and in situ nodes were prevalent throughout the PACT general area cladograms (Greater Antilles, 55.9% biotic expansion, 44.1% in situ; Hawaiian Islands, 40.6% biotic expansion, 59.4% in situ). Of the biotic expansion events, both forward and backward events occurred in both regions (Greater Antilles, 85.1% forward, 14.9% backward; Hawaiian Islands, 65% forward, 35% backward). Additionally, there is a power‐law SAR for the Greater Antilles but not for the Hawaiian Islands. However, exclusion of Hawai'i (the youngest, largest Hawaiian Island) produced a power‐law SAR for the Hawaiian Islands. Main conclusions The prevalence of in situ events as well as forward and backward biotic expansion events reveals that both Hawaiian and Greater Antillean biotas have evolved through alternating episodes of biotic expansion and in situ diversification. These patterns are characteristic of the taxon pulse dynamic, for which few data have previously been recorded on islands. Additionally, our analysis revealed that historical influences on the power‐law SARs are pronounced in both assemblages: old, small islands are relatively species rich and young, large islands are relatively species poor. Thus, our PACT results are consistent with hypotheses of geological influence on the evolution of island biotas and also provide greater insight into the role of the taxon pulse dynamic in the formation of island equilibria.  相似文献   

6.
Three species ofBactris are recognized in the Greater Antilles:B. cubensis (from Cuba),B. plumeriana (from Hispaniola), andB. jamaicana (from Jamaica). A cladistic analysis of the non-ocreate clade—i.e.,Bactris cubensis, B. plumeriana, B. jamaicana, B. macana, andB. gasipaes—confirmed that the Greater Antillean species ofBactris form a monophyletic group, i.e., the Antillean clade. Synapomorphies supporting the Antillean clade are mesocarp and endocarp fibers numerous, parallel, predominantly narrow, few broad, extending the entire length of the endocarp; and leaf segments 45–80 per side of rachis. The presence of fiber-sclereids in the leaf lamina, and petals of the staminate flowers ovate to ovatetrullate, with sparsely branched fibers, may represent additional synapomorphies.Bactris plumeriana andB. jamaicana are hypothesized to be sister species, a grouping weakly supported by their short anthers. Each species has at least one autapomorphy; therefore, all are considered to be a cladospecies. Noteworthy interpopulational variation occurs withinBactris plumeriana andB. cubensis.  相似文献   

7.
We used sequence variation in the mtDNA control-region and ND2 and cyt b genes to assess the systematics and biogeography of the five species of pupfish (Cyprinodon) on Hispaniola. These include four endemics, the relatively large-bodied Cyprinodon bondi, Cyprinodon nichollsi, and Cyprinodon sp., each from a separate lake in southwestern Hispaniola, and Cyprinodon higuey from a coastal lake in eastern Hispaniola. The fifth species consists of coastal populations referable to Cyprinodon variegatus riverendi. The results indicate that Hispaniola has been invaded by at least two forms, first by a late Pliocene progenitor of Cyprinodon variegatus ovinus and the large-bodied Hispaniolan species, and, more recently, by one or more ancestral forms allied with Cyprinodon variegatus variegatus and C. v. riverendi. Levels of divergence indicate that large expanses of open sea have not acted as long-term barriers to inter-island dispersal of cyprinodontiform fishes. This study, together with the molecular systematics of other insular Caribbean fishes, indicates that most insular groups originated from late Neogene dispersal from the mainland. The patterns of mtDNA variation in Cyprinodon showed little congruence with the species/subspecies taxonomy.  相似文献   

8.
9.
James W. Haefner 《Oecologia》1988,77(1):107-117
Summary Using published data, a Monte Carlo approach was used to determine if niche shifts in communities of Anolis lizards have occurred within two islands in the Greater Antilles. Communities at 4 sites on Puerto Rico and 4 sites on Jamaica were randomly assembled using resource-use data from any of the 4 sites with the constraint that the species list of the random community was identical to that observed for each site. The observed niche structure and that of the randomly assembled community were compared at each site. The null hypothesis tested was that one of several functions of niche overlap did not produce lower values in the observed communities compared to those randomly assembled. The sensitivity of this method to details of the analysis was investigated by using 5 variations on the procedure for quantifying the niche structure of the communities. I investigated the effects of (1) using Pianka's versus Levins' metric of niche overlap, (2) using complete resource-use data versus the marginals of the distributions, (3) asymmetric responses to overlap due to size differences between overlapping species, (4) using estimated electivities versus the observed proportional use of resource states, and (5) methods of niche analysis based on different degrees of biological resolution (e.g., community-wide statistics versus individual species responses). The results of the simulations and statistical comparisons did not provide a clear, unambiguous answer to the question of the occurrence of niche shifts. Statistical evidence for niche shifts was more frequently detected using Levins' metric compared to Pianka's, and shifts were easier to detect using high biological resolution (examination of individual species) compared to community-wide measures of niche structure response.  相似文献   

10.
Colonization of islands can dramatically influence the evolutionary trajectories of organisms, with both deterministic and stochastic processes driving adaptation and diversification. Some island colonists evolve extremely large or small body sizes, presumably in response to unique ecological circumstances present on islands. One example of this phenomenon, the Greater Antillean boas, includes both small (<90 cm) and large (4 m) species occurring on the Greater Antilles and Bahamas, with some islands supporting pairs or trios of body‐size divergent species. These boas have been shown to comprise a monophyletic radiation arising from a Miocene dispersal event to the Greater Antilles, though it is not known whether co‐occurrence of small and large species is a result of dispersal or in situ evolution. Here, we provide the first comprehensive species phylogeny for this clade combined with morphometric and ecological data to show that small body size evolved repeatedly on separate islands in association with specialization in substrate use. Our results further suggest that microhabitat specialization is linked to increased rates of head shape diversification among specialists. Our findings show that ecological specialization following island colonization promotes morphological diversity through deterministic body size evolution and cranial morphological diversification that is contingent on island‐ and species‐specific factors.  相似文献   

11.
Heroine cichlids are the second largest and very diverse tribe of Neotropical cichlids, and the only cichlid group that inhabits Mesoamerica. The taxonomy of heroines is complex because monophyly of most genera has never been demonstrated, and many species groups are without applicable generic names after their removal from the catch-all genus Cichlasoma (sensu Regan, 1905). Hence, a robust phylogeny for the group is largely wanting. A rather complete heroine phylogeny based on cytb sequence data is available [Concheiro Pérez, G.A., Říčan O., Ortí G., Bermingham, E., Doadrio, I., Zardoya, R. 2007. Phylogeny and biogeography of 91 species of heroine cichlids (Teleostei: Cichlidae) based on sequences of the cytochrome b gene. Mol. Phylogenet. Evol. 43, 91–110], and in the present study, we have added and analyzed independent data sets (nuclear and morphological) to further confirm and strengthen the cytb-phylogenetic hypothesis. We have analyzed a combined cytb-nuclear (RAG1 and two S7 introns) data set of 48 species representing main heroine lineages to achieve further resolution of heroine higher taxonomic levels and a combined cytb-morphological data set of 92 species to stabilize generic taxonomy. The recovered phylogenies supported the circumamazonian—CAM—Heroini (sensu Concheiro Peréz et al., 2007) as a monophyletic group, that could be divided into six main clades: (1) australoheroines (the southernmost heroine genus Australoheros), (2) nandopsines (the Antillean genus Nandopsis), (3) caquetaines (including the north western Amazonian genera Caquetaia and Heroina), (4) astatheroines (including Astatheros, Herotilapia and Rocio), (5) amphilophines (including Amphilophus and related genera), and (6) herichthyines (including Herichthyis and related genera). Nuclear and mitochondrial data partitions arrived at highly congruent topologies. Suprageneric relationships were influenced mainly by the nuclear signal, as well as the most basal phylogenetic position of Australoheros within CAM heroines. The new phylogeny of the tribe Heroini provides robust framework to stabilize the taxonomy of the group and for future comparative studies on these morphologically and ecologically diverse freshwater fishes. Morphology was mostly informative at the genus level and aid in determining the monophyly and composition of heroine genera. Upon acceptance of all putative genera, as recovered in this study, the Heroini would be with 35 genera the most genus-rich clade of Neotropical cichlids.  相似文献   

12.
Phylogeny and biogeography of Caribbean mammals   总被引:1,自引:0,他引:1  
Vicariance and dispersal hypotheses have been proposed over the last two hundred years to explain the distribution, diversity, and faunal composition of the Caribbean biota. Despite great advances in understanding the geological history of the region, recent biogeographical reviews have not used historical biogeographical methods. In this paper I review the taxonomy, distribution and phylogeny of all Cenozoic Caribbean non‐volant mammals and four bat lineages, and present reconciled trees for available phylogenies. Dates available from the fossil record and hypotheses of divergence based on molecular phylogenetic studies are also included in general assessments of fit between proposed geological models and Caribbean mammal diversification. The evidence posited in mammalian phylogenies does not add to the argument of dispersal vs. vicariance. One previously unidentified temporal pattern, the colonization of the Caribbean by South American mammals between the Palaeocene and the Middle Miocene, accounts for the distribution and phylogeny of the majority of lineages studied. Choloepodine and megalocnine sloths, hystricognath rodents, and primates all arrived during this window of colonization. Of these, megalocnine sloths, hystricognath rodents, Brachyphylla and allied bats, Stenodermatina bats, and primates fit the pattern of divergence from the mainland implied by the Gaarlandia hypothesis. Sloths, rodents and primates also roughly fit the timing of arrival to the Caribbean implied by Gaarlandia. The remaining taxa show contradictory dates of divergence according to molecular clock estimates, and no taxa fit the predicted timing and pattern of divergence among Antillean landmasses under the Gaarlandia model. Choloepodine sloths, murid rodents, insectivorans, mormoopids, and natalids show patterns of divergence from the mainland that are inconsistent with the Gaarlandia hypothesis and seem to require taxon‐specific biogeographical explanations. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 81 , 373–394.  相似文献   

13.
Aim To use molecular data to test for dispersal structuring in the immigration history of an amphidromous community on an island. Location The Caribbean island of Puerto Rico. Methods Mitochondrial DNA sequences were obtained from 11 amphidromous species, including shrimps, fish and a gastropod, sampled from throughout the island. The timing of population expansion (TE) in each species was calculated using nucleotide variation and molecular clock dating methods. The order of species accumulation was then reconstructed (oldest to most recent estimate for TE), and groups of species with non‐overlapping estimates for TE were identified. The temporal span and average immigration rate for each group were calculated and compared with expectations of two previously published models of island immigration [the ‘dispersal‐structured model of island recolonization’ ( Whittaker & Jones, Oikos, 1994 , 69 , 524–529), which predicts short phases of rapid immigration followed by extended phases with relatively slow immigration rates; and the ‘colonization window hypothesis’ ( Carine, Taxon, 2005 , 54 , 895–903), which suggests that opportunities for island colonization are temporally constrained to discrete waves of colonization]. Results The molecular data indicated the immigration history of Puerto Rican amphidromous fauna from the late Pleistocene through the Holocene and identified two groups of species with non‐overlapping estimates for TE and one group that overlapped with the other two groups. The temporal span, average immigration rate and lack of discreteness between all three groups indicated a continuum of immigration rather than distinct phases of species arrivals. Main conclusions This study did not support the expectations of the immigration models and suggested that amphidromous species from Puerto Rico comprise a single class of marine‐based dispersers. The immigration sequence we report probably reflects a recolonization chronology in this community, in keeping with the notion of species turnover through time. Four areas of future research into the immigration history of amphidromous species on islands are identified, and indicated the possibility that equilibrium processes govern long‐term community change in amphidromous biota on islands.  相似文献   

14.
The voice of historical biogeography   总被引:2,自引:0,他引:2  
Historical biogeography is going through an extraordinary revolution concerning its foundations, basic concepts, methods, and relationships to other disciplines of comparative biology. There are external and internal forces that are shaping the present of historical biogeography. The external forces are: global tectonics as the dominant paradigm in geosciences, cladistics as the basic language of comparative biology and the biologist's perception of biogeography. The internal forces are: the proliferation of competing articulations, recourse to philosophy and the debate over fundamentals. The importance of the geographical dimension of life's diversity to any understanding of the history of life on earth is emphasized. Three different kinds of processes that modify the geographical spatial arrangement of the organisms are identified: extinction, dispersal and vicariance. Reconstructing past biogeographic events can be done from three different perspectives: (1) the distribution of individual groups (taxon biogeography) (2) areas of endemism (area biogeography), and (3) biotas (spatial homology). There are at least nine basic historical biogeographic approaches: centre of origin and dispersal, panbiogeography, phylogenetic biogeography, cladistic biogeography, phylogeography, parsimony analysis of endemicity, event-based methods, ancestral areas, and experimental biogeography. These nine approaches contain at least 30 techniques (23 of them have been proposed in the last 14 years). The whole practice and philosophy of biogeography depend upon the development of a coherent and comprehensive conceptual framework for handling the distribution of organisms and events in space.  相似文献   

15.
Summary. Compilation and analysis of the existing literature together with the results of our research carried out since 2000 makes possible an updated catalogue of the West Indian Odonata. Such a catalogue has not previously been available, and dispersed and multilingual literature did not facilitate odonatological studies. The odonate fauna of the Caribbean is currently composed of 108 valid species, of which 36 (32%) are endemic to one or a few islands. The most species-rich families are Libellulidae and Coenagrionidae, together comprising 65% of the total fauna.  相似文献   

16.
The diagnosis of the genus Labidochromis is revised to include species with bicuspid outer teeth. Sixteen species, of which 13 are new, are described and illustrated and the validity of five others is discussed. The interrelationships between members of the genus and the relationship of the genus to other genera are discussed. No clearly defined sister group to the genus has been found either within or outside the Lake Malawi cichlid species flock. A key based on the coloration of known species is included.  相似文献   

17.
Palaeobiogeographic reconstructions are underpinned by phylogenies, divergence times and ancestral area reconstructions, which together yield ancestral area chronograms that provide a basis for proposing and testing hypotheses of dispersal and vicariance. Methods for area coding include multi-state coding with a single character, binary coding with multiple characters and string coding. Ancestral reconstruction methods are divided into parsimony versus Bayesian/likelihood approaches. We compared nine methods for reconstructing ancestral areas for placental mammals. Ambiguous reconstructions were a problem for all methods. Important differences resulted from coding areas based on the geographical ranges of extant species versus the geographical provenance of the oldest fossil for each lineage. Africa and South America were reconstructed as the ancestral areas for Afrotheria and Xenarthra, respectively. Most methods reconstructed Eurasia as the ancestral area for Boreoeutheria, Euarchontoglires and Laurasiatheria. The coincidence of molecular dates for the separation of Afrotheria and Xenarthra at approximately 100 Ma with the plate tectonic sundering of Africa and South America hints at the importance of vicariance in the early history of Placentalia. Dispersal has also been important including the origins of Madagascar's endemic mammal fauna. Further studies will benefit from increased taxon sampling and the application of new ancestral area reconstruction methods.  相似文献   

18.
羊肚菌属分子系统学研究进展*   总被引:5,自引:0,他引:5  
胡克兴  董雪  范黎   《微生物学通报》2004,31(6):115-119
简要介绍羊肚菌属系统学研究现状,概述了当前国内外羊肚菌属分子系统学研究进展。  相似文献   

19.
苔藓植物分子系统学研究概况   总被引:1,自引:0,他引:1  
李晶  沙伟 《植物学通报》2004,21(2):172-179
结合同工酶分析技术及随机扩增多态性DNA(RAPD)、限制性片段长度多态性(RFLP)和DNA序列测序3种分子生物学技术,对苔藓植物的分子系统学研究概况进行了介绍,并指出了在苔藓植物分子系统学研究中存在的一些问题.  相似文献   

20.
Aim Through analysis of fossil records, the aim of this paper is to show that fossil representatives of at least three land‐mammal clades (pitheciine atelid primates, heteropsomyine echimyid rodents, and megalonychid phyllophagan xenarthrans) that once lived in the Greater Antilles are as old as, if not older than, ‘first’ occurrences of these same groups on the South American mainland. Location Greater Antilles, South America, Antarctic Peninsula. Methods Analysis of Cenozoic land‐mammal fossil records for the three areas. Results Comparison reveals an interesting similarity to the Tertiary vertebrate palaeontological record for the Antarctic Peninsula (Seymour Island), in the sense that the latter also includes early (Eocene) representatives of some typical ‘South American’ groups (e.g. meridiungulates, sloths, certain marsupial groups). Conclusions Given how limited the Antillean and Antarctic records are in quantity and quality, it seems unlikely that these ‘first’ appearances have much bearing on real origins (basal divergences). Rather, it suggests that the fossil basis for interpreting the origin and earliest diversification of ‘South American’ clades during the latest Cretaceous/early Cenozoic is probably even scantier than generally realized. In particular, the Antillean record strengthens arguments that some crown‐group continental lineages are considerably older than fossil evidence currently allows – a point increasingly (if unevenly) supported by molecular studies of many of the same clades.  相似文献   

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