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1.
Aim The genus Abies exemplifies plant diversification related to long‐term climatic, geological and evolutionary changes. Today, the Mediterranean firs comprise nine species, one natural hybrid and several varieties. Here I summarize current knowledge concerning the origin and evolution of the genus Abies in the Mediterranean Basin and propose a comprehensive hypothesis to explain the isolation and speciation pattern of Mediterranean firs. Location The Mediterranean Basin. Methods The literature on Abies was reviewed, focusing on the morphology, fossil records, molecular ecology, phytosociology and biogeography of the genus in the Mediterranean Basin. Results Abies fossils from the western Mediterranean indicate a wide Tertiary circum‐Mediterranean distribution of the Abies ancestor. Palaeogeographical data also suggest a single eastern Mediterranean Tertiary ancestor. Following the Miocene to Pliocene climate crisis and marine transgressions, the ancestor of the northern Mediterranean firs is hypothesized to have separated into two eastern groups, one on the Balkan Peninsula and the other in Asia Minor. However, land bridges may have permitted gene flow at times. A southward migration of A. alba to refugia, where older fir species may have remained isolated since the Miocene, could explain recent findings indicating that morphologically distant species are more closely related than expected based on such morphological classification. Main conclusions The Abies genus appears to have undergone significant morphological differentiation that does not necessarily imply reproductive isolation. That is, long‐term Mediterranean Basin dryness along a south‐eastern to north‐western gradient may have caused an initial Miocene–Pliocene speciation sequence. Pleistocene glacial cycles probably forced migrations to occur, leading to repeated contact between fir species in glacial refugia.  相似文献   

2.
Aim The Mediterranean region is often regarded as a crossroads where species of various origins meet. However, the biogeographical relationships between this region and contiguous Saharan, Macaronesian and Irano‐Turanian regions have not been investigated in detail. The aim of this study was to characterize the phylogeography of the circum‐Mediterranean species Myrtus communis and to investigate the origin of isolated central Saharan populations of Myrtus nivellei. Location The distribution ranges of M. communis from Macaronesia to the Irano‐Turanian region (173 sampled populations) and of M. nivellei in the mountains (Hoggar, Tassili n’Ajjer, Immidir, Tibesti) of the central Sahara (23 populations). Methods Nuclear ribosomal DNA (nrDNA) sequences of Myrtaceae were used to root the phylogeny of Myrtus, and to date its crown node, according to a detailed review of the palaeobotanical records used for multiple fossil calibration. Chloroplast DNA (cpDNA) sequences were analysed through the determination of genetic diversity indices and by statistical phylogeography. Results Both cpDNA and nrDNA markers indicated east–west genetic differentiation within M. communis. During the late Miocene, a key vicariance event affected the previous circum‐Mediterranean distribution of Myrtus, leading to the isolation of eastern populations. During the late Miocene or early Pliocene, two clades diverged: one is now scattered in the Mediterranean Basin and adjacent regions, whereas the other evolved in the western Mediterranean region. The differentiation of lineages during the Plio‐Pleistocene occurred mainly in the western part of the Mediterranean Basin, which has been at the origin of migrations towards Macaronesian islands and Saharan mountains. This is one of the first plant phylogeographical studies to report migrations from the Mediterranean to the Sahara. Main conclusions The genus Myrtus has persisted in the Mediterranean region since at least the Neogene and its biogeography reflects the cumulation of the species’ responses to successive palaeoenvironmental changes. The current distribution of the genus Myrtus in the Mediterranean Basin and in isolated areas, such as the Macaronesian islands and Saharan mountains, can be explained by the striking ability of this plant not only to persist locally in various refugia, but also to migrate.  相似文献   

3.
Carcinus aestuarii Nardo, 1847 is a widespread coastal crab species throughout the Mediterranean Sea with a pelagic larval phase. This species tolerates a wide range of environmental conditions and typically inhabits fragmented habitats, such as embayments, lagoons and estuaries. It is therefore a good candidate species for studying and testing different phylogeographical hypotheses in the Mediterranean Sea. By contrast to its Atlantic sister species, Carcinus maenas, studies on the population genetic structure of C. aestuarii in its native range are still scarce. In the present study, specimens from along the European Mediterranean Sea were collected and DNA‐sequenced and analyses were applied to discriminate between present day and historical factors influencing the population genetic structure of this species. The results obtained demonstrate the existence of two genetically distinct geographical groups, corresponding to the eastern and western Mediterranean, with further subdivision within the East Mediterranean Basin. A strong asymmetric gene flow was recorded toward the Eastern Basin, which may play a crucial role in shaping the present day biogeographical patterns of this species and potentially other sympatric ones with pelagic larvae. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 771–790.  相似文献   

4.
Hermann's tortoise (Testudo hermanni), the best-known western Palaearctic tortoise species, has a rare natural distribution pattern comprising the Mediterranean areas of the Iberian, Apennine, and Balkan Peninsulas, as well as Sicily, Corsica and Sardinia. The western part of this range is traditionally considered habitat for T. h. hermanni, while T. h. boettgeri occurs in the Balkans. Taxonomy of this tortoise has been challenged in recent years, with the two subspecies being considered full species and the central Dalmatian populations of T. h. boettgeri being considered a third species, T. hercegovinensis. Using an mtDNA fragment approximately 1150 bp long (cytochrome b gene and adjacent portion of tRNA-Thr gene), we investigated mtDNA diversity with regard to contrasting concepts of two subspecies or three species. Seven closely related haplotypes were identified from the western Mediterranean and 15 different, in part much-differentiated, haplotypes from the Balkans. Western Mediterranean haplotypes differ from Balkan haplotypes in 16–42 mutation steps. One to seven mutation steps occur within western Mediterranean populations. Balkan haplotypes, differing in 1−37 nucleotides, group in parsimony network analysis into three major assemblages that display, in part, a similar degree of differentiation to that of western Mediterranean haplotypes relative to Balkan haplotypes. Rates of sequence evolution are different in both regions, and low divergence, palaeogeography and the fossil record suggest a slower molecular clock in the western Mediterranean. While monophyly in western Mediterranean haplotypes is well-supported, conflicting evidence is obtained for Balkan haplotypes; maximum parsimony supports monophyly of Balkan haplotypes, but other phylogenetic analyses (Bayesian, ML, ME) indicate Balkan haplotypes could be paraphyletic with respect to the western Mediterranean clade. These results imply a process of differentiation not yet complete despite allopatry in the western Mediterranean and the Balkans, and suggest all populations of T. hermanni are conspecific. In the western Mediterranean no clear geographical pattern in haplotype distribution is found. Distribution of Balkan haplotypes is more structured. One group of similar haplotypes occurs in the eastern Balkans (Bulgaria, Republic of Macedonia, Romania and the Greek regions Evvia, Macedonia, Peloponnese, Thessaly and Thrace). Two distinct haplotypes, differing in eight to nine mutation steps from the most common haplotype of the first group, are confined to the western slope of the Taygetos Mts. in the Peloponnese. Yet another group, connected over between four and 23 mutation steps with haplotypes of the eastern Balkan group, occurs along the western slope of the Dinarid and Pindos Mts. (Istria, Dalmatia, western Greece). Taygetos haplotypes are nested within other haplotypes in all phylogenetic analyses and support for monophyly of the other Balkan groups is at best weak. We conclude that using the traditional two subspecies model should be continued for T. hermanni. Phylogeographies of T. hermanni and Emys orbicularis, another codistributed chelonian, are markedly different, but share a few similarities. Both were forced to retreat to southern refuges during Pleistocene glaciations. With the advent of Holocene warming, E. orbicularis underwent rapid range expansion and temperate regions of Europe and adjacent Asia were recolonized from refuges in the Balkans and the northern Black Sea Region. By contrast, T. hermanni remained more or less confined to refuges and nearby regions, resulting in a much smaller range, and allopatric and parapatric distribution of haplotype groups and clades. MtDNA lineages are more diverse in E. orbicularis than they are in T. hermanni on southern European peninsulas, indicating several distinct glacial refuges in close proximity and extensive intergradation during Holocene range expansion for E. orbicularis. In T. hermanni it is likely that only on the Balkan Peninsula was more than one refuge located, corresponding to the parapatric ranges of haplotype groups currently there. On the old western Mediterranean islands Corsica and Sardinia no differentiated (E. orbicularis) or only weakly differentiated haplotypes (T. hermanni) occur, even though there is evidence for the presence of both species on Corsica since at least the Middle Pleistocene. High mountain chains constitute major barriers separating distinct mtDNA clades or groups in each species.  相似文献   

5.
The predatory mitePhytoseiulus persimilis Athias-Henriot is widely used for biological control of spider mites in greenhouse. Despite its records from various Mediterranean countries,P. persimilis was not recorded from Turkey. Here we report the natural colonies ofP. persimilis observed along the Mediterranean coast of Turkey.  相似文献   

6.
The Brassy Chub, Kyphosus vaigiensis, first recorded in the Mediterranean in 1998, is reported herein from the coast of Israel. The identity of the specimen was confirmed by morphological and molecular analysis. This is the first record of K. vaigiensis from the Eastern Mediterranean. The possible origins of the Israeli record is discussed.  相似文献   

7.
Aim The Mediterranean region is a species‐rich area with a complex geographical history. Geographical barriers have been removed and restored due to sea level changes and local climatic change. Such barriers have been proposed as a plausible mechanism driving the high levels of speciation and endemism in the Mediterranean basin. This raises the fundamental question: is allopatric isolation the mechanism by which speciation occurs? This study explores the potential driving influence of palaeo‐geographical events on the speciation of Cyclamen (Myrsinaceae), a group with most species endemic to the Mediterranean region. Cyclamen species have been shown experimentally to have few genetic barriers to hybridization. Location The Mediterranean region, including northern Africa, extending eastwards to the Black Sea coast. Methods A generic level molecular phylogeny of Myrsinaceae and Primulaceae is constructed, using Bayesian approximation, to produce a secondary age estimate for the stem lineage of Cyclamen. This estimate is used to calibrate temporally an infrageneric phylogeny of Cyclamen, built with nrDNA ITS, cpDNA trnL‐F and cpDNA rps16 sequences. A biogeographical analysis of Cyclamen is performed using dispersal–vicariance analysis. Results The emergence of the Cyclamen stem lineage is estimated at 30.1–29.2 Ma, and the crown divergence at 12.9–12.2 Ma. The average age of Cyclamen species is 3.7 Myr. Every pair of sister species have mutually exclusive, allopatric distributions relative to each other. This pattern appears typical of divergence events throughout the evolutionary history of the genus. Main conclusions Geographical barriers, such as the varying levels of the Mediterranean Sea, are the most plausible explanation for speciation events throughout the phylogenetic history of Cyclamen. The genus demonstrates distributional patterns congruent with the temporally reticulate palaeogeography of the Mediterranean region.  相似文献   

8.
A specimen of the largescaled terapon Terapon theraps was recorded for the first time from the Mediterranean Sea. The finding of T. theraps in the northernmost part of the Mediterranean Sea raises the number of Lessepsian migrant species to at least 68 and in the Adriatic Sea to at least 11.  相似文献   

9.
10.
Lithophyllum species in the Mediterranean Sea function as algal bioconstructors, contributing to the formation of biogenic habitats such as coralligenous concretions. In such habitats, thalli of Lithophyllum, consisting of crusts or lamellae with entire or lobed margins, have been variously referred to as either one species, L. stictiforme, or two species, L. stictiforme and L. cabiochiae, in the recent literature. We investigated species diversity and phylogenetic relationships in these algae by sequencing three markers (psbA and rbcL genes, cox2,3 spacer), in conjunction with methods for algorithmic delimitation of species (ABGD and GMYC). Mediterranean subtidal Lithophyllum belong to a well‐supported lineage, hereby called the L. stictiforme complex, which also includes two species described from the Atlantic, L. lobatum and L. searlesii. Our results indicate that the L. stictiforme complex consists of at least 13 species. Among the Mediterranean species, some are widely distributed and span most of the western and central Mediterranean, whereas others appear to be restricted to specific localities. These patterns are interpreted as possibly resulting from allopatric speciation events that took place during the Messinian Salinity Crisis and subsequent glacial periods. A partial rbcL sequence from the lectotype of L. stictiforme unambiguously indicates that this name applies to the most common subtidal Lithophyllum in the central Mediterranean. We agree with recent treatments that considered L. cabiochiae and L. stictiforme conspecific. The diversity of Lithophyllum in Mediterranean coralligenous habitats has been substantially underestimated, and future work on these and other Mediterranean corallines should use identifications based on DNA sequences.  相似文献   

11.
Hexanchus nakamurai is a deep-water species, with very little scientific information. This study confirms the distribution of the species in the most eastern region of the Mediterranean Sea, Levantine Sea, in addition to providing some biological information from four pregnant individuals, which is being reported for the first time in the Mediterranean Sea. A total of four individuals were bycaught, in two sets on opposite coasts, three on the 13th of May 2020 from the western coast, and an individual on the 14th June 2020 from east coast of the island of Cyprus. The four specimens, all pregnant females, measured between 107 and 116 cm in total length and between 4,330 and 4,960 g in weight. All specimens were in early pregnancy according to the level of embryo development, which confirms that the size at maturity is smaller than previously reported. In the stomachs, remains of the hake Merluccius merluccius, the cephalopod Loligo vulgaris and two unidentified species of Hirudinea (Annelida) were found. This study provides important new information on the Mediterranean distribution of a globally rare and data deficient species, including an expansion of its known range, dietary preferences and insights of its reproduction biology; the first pregnant females reported in the Mediterranean Sea.  相似文献   

12.
The life cycle and autoecology of three Mediterranean thorny species,Onopordum nervosum (Iberian endemic),Cirsium scabrum (Western Mediterranean) andCarthamus arborescens (Iberian-North African), of potential use in agriculture as bioenergetic, forage or oil producing plants were studied. These threeCardueae spp. are good examples of ways in which Mediterranean plants adapt their typical annual cycle to avoid summer droughts.O. nervosum is a perennial, monocarpic, heliophilous species which flowers in early summer and grows even under the extreme xeric conditions of the Mediterranean summers. It is a basiphilous plant usually found in sandy-loamy and sandy-clayey-loamy soils with a marked geographical variability in its seed germination.C. scabrum is a perennial, monocarpic species which has a long life cycle, flowering in summer and growing only during the wet months. It is not well-adapted to droughts and is usually restricted to acid soils.C. arborescens is a perennial, polycarpic species which flowers in spring and dries up in summer. It is usually found in basic loamy-sandy or sandy-loamy soils poor in organic matter.  相似文献   

13.
In the Mediterranean Sea, where biological invasions constitute a serious threat, the combination of citizen science and social networks amplified the power of proper field studies, recording species that would have otherwise presumably passed unnoticed. Based on data collected on several Facebook groups, we hereby first report the presence of five fish taxa (Kyphosus sp., Heniochus intermedius, Pomacanthus imperator, Pomacanthus maculosus and Abudefduf sp.) new for the Mediterranean Egypt, revise their distribution in the Mediterranean Sea and discuss their possible introduction pathways. Finally, we provide some considerations on the potentiality of social media for citizen science projects.  相似文献   

14.
At the intersection of geological activity, climatic fluctuations, and human pressure, the Mediterranean Basin – a hotspot of biodiversity – provides an ideal setting for studying endemism, evolution, and biogeography. Here, we focus on the Roucela complex (Campanula subgenus Roucela), a group of 13 bellflower species found primarily in the eastern Mediterranean Basin. Plastid and low‐copy nuclear markers were employed to reconstruct evolutionary relationships and estimate divergence times within the Roucela complex using both concatenation and species tree analyses. Niche modeling, ancestral range estimation, and diversification analyses were conducted to provide further insights into patterns of endemism and diversification through time. Diversification of the Roucela clade appears to have been primarily the result of vicariance driven by the breakup of an ancient landmass. We found geologic events such as the formation of the mid‐Aegean trench and the Messinian Salinity Crisis to be historically important in the evolutionary history of this group. Contrary to numerous past studies, the onset of the Mediterranean climate has not promoted diversification in the Roucela complex and, in fact, may be negatively affecting these species. This study highlights the diversity and complexity of historical processes driving plant evolution in the Mediterranean Basin.  相似文献   

15.
S. Perea  I. Doadrio 《Molecular ecology》2015,24(14):3706-3722
The Mediterranean freshwater fish fauna has evolved under constraints imposed by the seasonal weather/hydrological patterns that define the Mediterranean climate. These conditions have influenced the genetic and demographic structure of aquatic communities since their origins in the Mid‐Pliocene. Freshwater species in Mediterranean‐type climates will likely constitute genetically well‐differentiated populations, to varying extents depending on basin size, as a consequence of fragmentation resulting from drought/flood cycles. We developed an integrative framework to study the spatial patterns in genetic diversity, demographic trends, habitat suitability modelling and landscape genetics, to evaluate the evolutionary response of Mediterranean‐type freshwater fish to seasonal fluctuations in weather. To test this evolutionary response, the model species used was Squalius valentinus, an endemic cyprinid of the Spanish Levantine area, where seasonal weather fluctuations are extreme, although our findings may be extrapolated to other Mediterranean‐type species. Our results underscore the significant role of the Mediterranean climate, along with Pleistocene glaciations, in diversification of S. valentinus. We found higher nuclear diversity in larger drainage basins, but higher mitochondrial diversity correlated to habitat suitability rather than basin size. We also found strong correlation between genetic structure and climatic factors associated with Mediterranean seasonality. Demographic and migration analyses suggested population expansion during glacial periods that also contributed to the current genetic structure of S. valentinus populations. The inferred models support the significant contribution of precipitation and temperature to S. valentinus habitat suitability and allow recognizing areas of habitat stability. We highlight the importance of stable habitat conditions, fostered by typical karstic springs found on the Mediterranean littoral coasts, for the preservation of freshwater species inhabiting seasonally fluctuating river systems.  相似文献   

16.
The yellowmouth barracuda, Sphyraena viridensis, is a Mediterranean native species whose exact distribution is uncertain due to a long‐term taxonomic confusion with Sphyraena sphyraena. Records of this species in the Mediterranean Sea have recently increased, and a northwards expansion of its distribution has been suggested. Three mtDNA regions, namely cytochrome oxidase I, cytochrome b and the control region, were analysed in S. viridensis samples from Italian coastal regions to provide molecular markers useful in species identification, in phylogenetic analysis and in detecting the distribution of genetic variability of the yellowmouth barracuda in this area. The data clearly distinguish S. viridensis from S. sphyraena and the other four (one native and three Lessepsian) Mediterranean Sphyraena species and identify two clearly distinct lineages that diverged during the Pleistocene but are currently panmictic in the investigated area. Both lineages retain signatures of historical population expansion. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 635–641.  相似文献   

17.
Aim The aim of this study was to describe the composition, community structure and biogeographical variation of subtidal algal assemblages dominated by the brown alga Cystoseira crinita across the Mediterranean Sea. Location The Mediterranean coast, from Spain (1°25′ E) to Turkey (30°26′ E). Methods Data on the species composition and structure of assemblages dominated by the species C. crinita were collected from 101 sites in nine regions across the Mediterranean Sea. Multivariate and univariate statistical tools were used to investigate patterns of variation in the composition of the assemblages among sites and regions, and to compare these with previously defined biogeographical regions. Linear regressions of species richness versus longitude and versus latitude were also carried out to test previously formulated hypotheses of biodiversity gradients in the Mediterranean Sea. Results The main features characterizing C. crinita‐dominated assemblages across the Mediterranean included a similar total cover of species, a similar cover of C. crinita, and consistency in the presence of the epiphyte Haliptilon virgatum. Biogeographical variation was detected as shifts in relative abundances of species among regions, partly coinciding with previously described biogeographical sectors. A significant positive correlation was found between species richness and latitude, while no significant correlation was detected between species richness and longitude. Main conclusions The patterns of variation in community structure detected among the studied regions reflected their geographical positions quite well. However, latitude seemed to contribute more to the explanation of biological patterns of diversity than did geographical distances or boundaries, which classically have been used to delimit biogeographical sectors. Moreover, the positive correlation between species richness and latitude reinforced the idea that latitude, and possibly temperature as a related environmental factor, plays a primary role in structuring biogeographical patterns in the Mediterranean Sea. The lack of correlation between species richness and longitude contradicts the notion that there is a decrease in species richness from west to east in the Mediterranean, following the direction of species colonization from the Atlantic.  相似文献   

18.
19.
Understanding the demographic history and genetic make‐up of colonizing species is critical for inferring population sources and colonization routes. This is of main interest for designing accurate control measures in areas newly colonized by vector species of economically important pathogens. The biting midge Culicoides imicola is a major vector of orbiviruses to livestock. Historically, the distribution of this species was limited to the Afrotropical region. Entomological surveys first revealed the presence of C. imicola in the south of the Mediterranean basin by the 1970s. Following recurrent reports of massive bluetongue outbreaks since the 1990s, the presence of the species was confirmed in northern areas. In this study, we addressed the chronology and processes of C. imicola colonization in the Mediterranean basin. We characterized the genetic structure of its populations across Mediterranean and African regions using both mitochondrial and nuclear markers, and combined phylogeographical analyses with population genetics and approximate Bayesian computation. We found a west/east genetic differentiation between populations, occurring both within Africa and within the Mediterranean basin. We demonstrated that three of these groups had experienced demographic expansions in the Pleistocene, probably because of climate changes during this period. Finally, we showed that C. imicola could have colonized the Mediterranean basin in the Late Pleistocene or Early Holocene through a single event of introduction; however, we cannot exclude the hypothesis involving two routes of colonization. Thus, the recent bluetongue outbreaks are not linked to C. imicola colonization event, but rather to biological changes in the vector or the virus.  相似文献   

20.
During the Iron Age, sea trade in the Mediterranean increased, particularly with the expansion of Phoenician and Greek colonies in the Western Mediterranean. A side effect of these human movements was the involuntary dispersion of commensal species, such as the house mouse (Mus musculus domesticus). One archaeological layer dated from the 4th Century BC, coming from an Iberian village located in the Mediterranean coast of Spain, contained a large and reliable accumulation of small mammals. The presence of the house mouse was highly suspected within this layer. To assess its abundance quantitatively, we used a geometric morphometrics approach of the first lower molar contour using elliptical Fourier analysis. We also increased the power of the discrimination between the Algerian mouse (Mus spretus) and the house mouse by combining a dimension reduction approach together with different validation procedures. The relative importance of age, sex, and geographical origin onto the shape and form of the lower molar contour was also investigated. The results obtained demonstrate the presence and the dominance of the house mouse in the landscape surrounding the Iberian village in the 1st Millennium BC, only a few centuries after its arrival in the Western Mediterranean Basin. A cross‐validated linear discriminant function considering different Mediterranean populations suggest Morocco and France as the most probable geographical origins for the Algerian mouse, and Tunisia for the origin of house mice in North‐Eastern Spain. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102 , 483–497.  相似文献   

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