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1.
The present distribution of the carob-tree ( Ceratonia siliqua L.) throughout the coastal regions of the Mediterranean, the route followed from its possible place of origin in southern Arabia and the Horn of Africa, and the possible circumstances of the tree's domestication are discussed in the light of botanical, archaeological, historical and philological evidence. It is shown that the genus Ceratonia formed part of the wild flora of western Europe in preglacial times, that C. siliqua was present in ancient times in the Middle East and that its spread to the western Mediterranean area took place progressively, possibly beginning in the second millennium bc . From the fact that, except in the case of Greece and southern Italy, most of the names applied to the tree today in European languages are linked to Arabic, it is inferred that today's cultivars were probably selected by Muslims in the Middle Ages.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 431–436.  相似文献   

2.
Dehaasia pugerensis Koord. & Valeton is a threatened Indonesian Lauraceae species. It is an endemic tree known only from Jember Regency in East Java. To enhance the conservation of D. pugerensis, we conducted a population survey in several locations in Jember where the species were previously collected. The objectives were to: i) assess the current population status of D. pugerensis, ii) collect plant materials (seed, seedling, or cutting) to serve as ex situ collections, and iii) update the conservation status of the species according to IUCN Red List Category and Criteria. We only found D. pugerensis in 6 out of 16 locations in Wuluhan and Ambulu District during the survey. We successfully located 560 individuals of the species, of which 194 individuals (34.6%) were in the mature stage. Based on the diameter and height classes, the population of D. pugerensis formed a reverse J-shaped size distribution. We successfully collected 23 seeds and 15 seedlings of the species for ex situ collections. Our findings showed that the current status of D. pugerensis is Critically Endangered (CR) based on criteria B1ab(i,ii,iii,iv,v)and C2a(ii). Under these categories, the species faces an extremely high risk of extinction in the wild. Therefore, prompt comprehensive conservation actions are needed to ensure the survival of the species.  相似文献   

3.
The succession of early species of the genus Kepplerites is established in the Upper Bathonian-Lower Callovian beds of Central Russia and compared with the ammonoid succession of East Greenland and Western Europe. Late Bathonian members of the genus Kepplerites from the Middle Volga Region are generally similar, though not identical to those from Greenland, whereas the Early Callovian Kepplerites species and their immediate Bathonian ancestors are represented by species common to all three regions. The analysis of the ammonoid distribution suggests a connection between the East Greenland and Central Russian marine basins in the Early and Middle Bathonian and in the Early Callovian, and their short-term isolation in the Late Bathonian. A new species, Kepplerites (Kepplerites) aigii sp. nov., is described from the Upper Bathonian (keuppi Zone) of the Alatyr River basin (Middle Volga Region).  相似文献   

4.
Mesoamerican biodiversity is increasingly threatened by anthropogenic destruction of natural land cover. Habitat degradation and climate change are primary threats to specialized forest odonate species that are important model organisms for forest health and defining conservation units. The extreme niche specialization of Megaloprepus caerulatus, the world’s largest extant odonate, makes it well suited as an indicator for changing environmental conditions. Megaloprepus, which is considered to be a monospecific genus, is highly dependent on old growth forests whose water filled tree holes are limiting reproductive resources for this species. Here, we focus on the question how historical and recent fragmentation events, strong niche conservatism and ecological conditions have affected population dynamics, viability and the species status in this evolutionarily old genus. Two mitochondrial sequence markers (ND1 and 16S rRNA) and a set of microsatellites were used to analyze population structure and genetic diversity of M. caerulatus in the northern part of its distributional range. Results suggested an absence of gene flow and no shared haplotypes among the study populations. Statistical parsimony indicated high sub-structuring among populations with sequence diversity similar to levels found at the species level compared to other odonates. In sum, the genetic data suggest that Megaloprepus may actually consist of more than one species. The taxonomic status of the group should be revised in light of the three distinct genetic clusters found in different forest regions. The results may also allow insights into the impact of recent and historical habitat fragmentation on a strong Neotropical forest restricted insect species.  相似文献   

5.
The biogeographical relationships between far-separated populations, in particular, those in the mainland and islands, remain unclear for widespread species in eastern Asia where the current distribution of plants was greatly influenced by the Quaternary climate. Deciduous Oriental oak (Quercus variabilis) is one of the most widely distributed species in eastern Asia. In this study, leaf material of 528 Q. variabilis trees from 50 populations across the whole distribution (Mainland China, Korea Peninsular as well as Japan, Zhoushan and Taiwan Islands) was collected, and three cpDNA intergenic spacer fragments were sequenced using universal primers. A total of 26 haplotypes were detected, and it showed a weak phylogeographical structure in eastern Asia populations at species level, however, in the central-eastern region of Mainland China, the populations had more haplotypes than those in other regions, with a significant phylogeographical structure (N ST = 0.751> G ST = 0.690, P<0.05). Q. variabilis displayed high interpopulation and low intrapopulation genetic diversity across the distribution range. Both unimodal mismatch distribution and significant negative Fu’s FS indicated a demographic expansion of Q. variabilis populations in East Asia. A fossil calibrated phylogenetic tree showed a rapid speciation during Pleistocene, with a population augment occurred in Middle Pleistocene. Both diversity patterns and ecological niche modelling indicated there could be multiple glacial refugia and possible bottleneck or founder effects occurred in the southern Japan. We dated major spatial expansion of Q. variabilis population in eastern Asia to the last glacial cycle(s), a period with sea-level fluctuations and land bridges in East China Sea as possible dispersal corridors. This study showed that geographical heterogeneity combined with climate and sea-level changes have shaped the genetic structure of this wide-ranging tree species in East Asia.  相似文献   

6.
Pinus pinaster is one of the most popular conifers used for reforestation in Morocco and represents an economically and ecologically important species for the region. In this study, nuclear microsatellites (ncSSRs) are used to compare genetic structure and diversity estimates of natural populations of Moroccan maritime pine. Samples were collected among 10 natural populations distributed in three biogeographically different regions, the Rif Mountain, the Middle and the High Atlas. Forty-five nuclear alleles at seven variable loci were found with a mean of 6.4 alleles per locus. A number of private alleles (17.1%) were shown in populations from Rif and Middle Atlas. Moreover, in Morocco, P. pinaster showed a lower genetic diversity than in other parts of its geographic range. Significant departures from Hardy–Weinberg equilibrium with excess homozygosity are observed indicating a high level of mating inside populations. Genetic diversity was structured with high variability among populations (Fst = 12%). Results show a correlation between genetic and geographic distances with an R-squared of 0.436. Two clusters were found using STRUCTURE, whereas three main clusters can be distinguished based on genetic distances of phylogenetic tree. Genetic relationships among maritime pine populations in Morocco appear to be related to historical, ecological as well as anthropogenic factors, suggesting the need for conservation strategies at the population level.  相似文献   

7.
The phylogenetic status of the well-known Asian butterflies often known as Agehana (a species group, often treated as a genus or a subgenus, within Papilio sensu lato) has long remained unresolved. Only two species are included, and one of them especially, Papilio maraho, is not only rare but near-threatened, being monophagous on its vulnerable hostplant, Sassafras randaiense (Lauraceae). Although the natural history and population conservation of “Agehana” has received much attention, the biogeographic origin of this group still remains enigmatic. To clarify these two questions, a total of 86 species representatives within Papilionidae were sampled, and four genes (concatenated length 3842 bp) were used to reconstruct their phylogenetic relationships and historical scenarios. Surprisingly, “Agehana” fell within the American Papilio subgenus Pterourus and not as previously suggested, phylogenetically close to the Asian Papilio subgenus Chilasa. We therefore formally synonymize Agehana with Pterourus. Dating and biogeographic analysis allow us to infer an intercontinental dispersal of an American ancestor of Asian Pterourus in the early Miocene, which was coincident with historical paleo-land bridge connections, resulting in the present “East Asia-America” disjunction distribution. We emphasize that species exchange between East Asia and America seems to be a quite frequent occurrence in butterflies during the Oligocene to Miocene climatic optima.  相似文献   

8.
Aim  Middle East brown bears ( Ursus arctos syriacus Hemprich and Ehrenberg, 1828) are presently on the edge of extinction. However, little is known of their genetic diversity. This study investigates that question as well as that of Middle East brown bear relationships to surrounding populations of the species.
Location  Middle East region of south-western Asia.
Methods  We performed DNA analyses on 27 brown bear individuals. Twenty ancient bone samples (Late Pleistocene to 20th century) from natural populations and seven present-day samples obtained from captive individuals were analysed.
Results  Phylogenetic analyses of the mitochondrial sequences obtained from seven ancient specimens identify three distinct maternal clades, all unrelated to one recently described from North Africa. Brown bears from Iran exhibit striking diversity (three individuals, three haplotypes) and form a unique clade that cannot be linked to any extant one. Individuals from Syria belong to the Holarctic clade now observed in Eastern Europe, Turkey, Japan and North America. Specimens from Lebanon surprisingly appear as tightly linked to the clade of brown bears now in Western Europe. Moreover, we show that U. a. syriacus in captivity still harbour haplotypes closely linked to those found in ancient individuals.
Main conclusion  This study brings important new information on the genetic diversity of brown bear populations at the crossroads of Europe, Asia and Africa. It reveals a high level of diversity in Middle East brown bears and extends the historical distribution of the Western European clade to the East. Our analyses also suggest the value of a specific breeding programme for captive populations.  相似文献   

9.
The pistachio tree (Pistacia vera) has long been cultivated in south-central Asia and throughout the Mediterranean region of southern Europe, north Africa and the Middle East. We examined genetic diversity and patterns of relatedness amongfifteen P. vera cultivars, representing germplasm originating from throughout this range, by using Random Amplified Polymorphic DNA (RAPD) markers. The resulting data were used to construct a similarity matrix and to perform a UPGMA cluster analysis. These analyses revealed two major clusters of P. vera germplasm: a Mediterranean cluster, which includes cultivars originatingfrom the Mediterranean region of Europe, north Africa and the Middle East; and an Iranian-Caspian cluster, comprising germplasm originating from locations east of the Zagros mountains plus ’Peters’, a cultivar selected as a seedling of unknown origin in the U.S.A. The data presented here, in combination with historical and geographical records, support the hypothesis that pistachio cultivation originated in or near the present natural range of the species and was spread by cultivation to the Mediterranean region of the Middle East. This more limited pool was the germplasm source for subsequent spread of pistachio by cultivation throughout the Mediterranean region.  相似文献   

10.
Although the status of Crinoidea (sea lilies and featherstars) as sister group to all other living echinoderms is well-established, relationships among crinoids, particularly extant forms, are debated. All living species are currently placed in Articulata, which is generally accepted as the only crinoid group to survive the Permian–Triassic extinction event. Recent classifications have recognized five major extant taxa: Isocrinida, Hyocrinida, Bourgueticrinina, Comatulidina and Cyrtocrinida, plus several smaller groups with uncertain taxonomic status, e.g., Guillecrinus, Proisocrinus and Caledonicrinus. Here we infer the phylogeny of extant Crinoidea using three mitochondrial genes and two nuclear genes from 59 crinoid terminals that span the majority of extant crinoid diversity. Although there is poor support for some of the more basal nodes, and some tree topologies varied with the data used and mode of analysis, we obtain several robust results. Cyrtocrinida, Hyocrinida, Isocrinida are all recovered as clades, but two stalked crinoid groups, Bourgueticrinina and Guillecrinina, nest among the featherstars, lending support to an argument that they are paedomorphic forms. Hence, they are reduced to families within Comatulida. Proisocrinus is clearly shown to be part of Isocrinida, and Caledonicrinus may not be a bourgueticrinid. Among comatulids, tree topologies show little congruence with current taxonomy, indicating that much systematic revision is required. Relaxed molecular clock analyses with eight fossil calibration points recover Articulata with a median date to the most recent common ancestor at 231–252 mya in the Middle to Upper Triassic. These analyses tend to support the hypothesis that the group is a radiation from a small clade that passed through the Permian–Triassic extinction event rather than several lineages that survived. Our tree topologies show various scenarios for the evolution of stalks and cirri in Articulata, so it is clear that further data and taxon sampling are needed to recover a more robust phylogeny of the group.  相似文献   

11.

Background

Hybridization can have complex effects on evolutionary dynamics in ants because of the combination of haplodiploid sex-determination and eusociality. While hybrid non-reproductive workers have been found in a range of species, examples of gene-flow via hybrid queens and males are rare. We studied hybridization in East African army ants (Dorylus subgenus Anomma) using morphology, mitochondrial DNA sequences, and nuclear microsatellites.

Results

While the mitochondrial phylogeny had a strong geographic signal, different species were not recovered as monophyletic. At our main study site at Kakamega Forest, a mitochondrial haplotype was shared between a "Dorylus molestus-like" and a "Dorylus wilverthi-like" form. This pattern is best explained by introgression following hybridization between D. molestus and D. wilverthi. Microsatellite data from workers showed that the two morphological forms correspond to two distinct genetic clusters, with a significant proportion of individuals being classified as hybrids.

Conclusions

We conclude that hybridization and gene-flow between the two army ant species D. molestus and D. wilverthi has occurred, and that mating between the two forms continues to regularly produce hybrid workers. Hybridization is particularly surprising in army ants because workers have control over which males are allowed to mate with a young virgin queen inside the colony.  相似文献   

12.
There are a total of 16 fossil cercopithecid specimens, representing at least 10 individuals, from the Chiwondo Beds of northern Malawi. The majority of this material is derived from the Middle Pliocene Unit 3A, but one specimen is from the Early Pliocene Unit 2. This latter specimen is from a papionin of indeterminate genus similar in size to Parapapio ado and Pliopapio alemui. Among the specimens from Unit 3A, two species can be diagnosed: an indeterminate species of Theropithecus, and a species of Parapapio similar in dental size to P. broomi. Neither of the genera from Unit 3A are exclusive to either East Africa or South Africa. Their relative abundances, however, are more similar to Middle Pliocene South African sites where Parapapio is the most common primate genus, and Theropithecus is comparatively rare. This is in contrast to similarly-aged East African sites where Theropithecus is by far the most abundant genus.  相似文献   

13.
A new spiriferid brachiopod species, Cyrtospirifer vjacheslavi, from the Middle Frasnian of the East European Platform is described. These spiriferide shells from the Middle Frasnian of central European Russia and Middle Timan assigned traditionally to Cyrtospirifer disjunctus for more then a century are not conspecific to British species and are here reassigned to Cyrtospirifer vjacheslavi sp. nov.  相似文献   

14.
The European snow vole Chionomys nivalis has a patchy distribution restricted to rocky habitats across southern Europe and the Near and Middle East. We carried out a phylogeographic study to provide a biogeographic scenario, based on molecular data, outlining the major processes that determined the current distribution of the species. The samples include 26 snow voles from 14 different populations across the entire species range from Spain to Anatolia and Israel. Nearly complete sequences (1037 bp) of the mitochondrial gene for cytochrome b were sequenced. Relationships among haplotypes were inferred with neighbour-joining, maximum likelihood, maximum parsimony analyses and minimum spanning network. An analysis of mismatch distribution was used to cast light on past demographic expansion. We found 22 different haplotypes that fall into six distinct lineages, all but one is supported by high bootstrap values with all methods. Four lineages are allopatric (Tatra Mts., Iberia, Balkans and Middle East) while divergent haplotypes from two lineages show sympatry in the Alps and the Apennines. The basal relationships of these lineages could not be established by any tree. The mean pairwise genetic distance between lineages ranges from 2.4 to 4.2%. The shape of the mismatch distribution indicated a past expansion event dating back to between 158 000 and 84 000 years ago. These data can be interpreted with the existence of southern glacial refugia (Iberia, Balkans, Middle East and Italy) and one additional northern glacial refugium. The lack of phylogenetic resolution among lineages and the shape of mismatch distribution are indicative of a simultaneous and rapid splitting due to a relatively fast initial expansion of populations. Moreover, the analysis supports the hypothesis of the European origin of C. nivalis and its subsequent eastward dispersion during the Middle Pleistocene.  相似文献   

15.
Polyploidization is a dominant feature of flowering plant evolution. However, detailed genomic analyses of the interpopulation diversification of polyploids following genome duplication are still in their infancy, mainly because of methodological limits, both in terms of sequencing and computational analyses. The shepherd's purse (Capsella bursa‐pastoris) is one of the most common weed species in the world. It is highly self‐fertilizing, and recent genomic data indicate that it is an allopolyploid, resulting from hybridization between the ancestors of the diploid species Capsella grandiflora and Capsella orientalis. Here, we investigated the genomic diversity of C. bursa‐pastoris, its population structure and demographic history, following allopolyploidization in Eurasia. To that end, we genotyped 261 C. bursa‐pastoris accessions spread across Europe, the Middle East and Asia, using genotyping‐by‐sequencing, leading to a total of 4274 SNPs after quality control. Bayesian clustering analyses revealed three distinct genetic clusters in Eurasia: one cluster grouping samples from Western Europe and Southeastern Siberia, the second one centred on Eastern Asia and the third one in the Middle East. Approximate Bayesian computation (ABC) supported the hypothesis that C. bursa‐pastoris underwent a typical colonization history involving low gene flow among colonizing populations, likely starting from the Middle East towards Europe and followed by successive human‐mediated expansions into Eastern Asia. Altogether, these findings bring new insights into the recent multistage colonization history of the allotetraploid C. bursa‐pastoris and highlight ABC and genotyping‐by‐sequencing data as promising but still challenging tools to infer demographic histories of selfing allopolyploids.  相似文献   

16.
The sweet potato whitefly, Bemisia tabaci (Gennadius), is a cryptic species complex composed of at least 24 different morphologically indistinguishable species. The considerable differences in the pest status across the complex, and the ability of some to develop resistance to, insecticides make awareness of their identity critical in terms of developing effective control measures. Previously, phylogenetic reconstructions have been used to identify different B. tabaci, but this approach is no longer necessary because of the existence of mitochondrial cytochrome oxidase one consensus sequences for each of the known species. We therefore use these consensus sequences to determine the identities of the members of the complex in Syria and Egypt and then used genetic networks to reveal the pattern of their genetic relatedness to other haplotypes in the species to which they were assigned. The results showed the presence of three species in Syria, AsiaII 1, Middle East–Asia Minor 1 (this equates to the global invader known commonly as the B biotype) and Mediterranean (this equates to the global invader known commonly as the Q biotype). Egypt was shown to have two cryptic species, Middle East–Asia Minor 1 and Mediterranean. In Syria, Middle East–Asia Minor 1 was found around Damascus only (south‐west Syria), while Mediterranean was found throughout Aleppo (northern Syria) and Hama (north central Syria). AsiaII 1 was found around Hims (south central Syria) and Damascus (south‐western Syria). In Egypt, Mediterranean was found in Cairo and Ismailia (central Upper Egypt), while Middle East–Asia Minor 1 was found in the remaining all parts of Upper Egypt, Suez, North Sinai, Port Said, Dakahila, Behera and Alexandria which cover the main agricultural zone of Egypt. Genetic relatedness of Syrian and Egyptian populations with each other and with rest of world is also discussed.  相似文献   

17.
Oak (Quercus spp.) and hornbeam (Carpinus spp.) are one of dominant tree species in East Asian temperate broad leaf deciduous forests and many insect species, including more than 65% of Lepidoptera species, feed on these trees. We sampled lepidopteran caterpillars from two 0.1 ha plots in a temperate forest to investigate the role of dominant trees (oaks and hornbeams) in herbivore community. In total, we identified 738 caterpillars from 223 Lepidopteran species on 34 tree species. Most caterpillar species were from species-rich families such as Geometridae 25% (56 spp.), Noctuidae, and Tortricidae. After excluding dominant trees, plant-herbivore network analyses showed increased network specialization and nestedness and decreased generality and vulnerability. These results suggest that oaks and hornbeams support a large Lepidopteran herbivore community, and co-occurring plant species support diverse but specific herbivores. Geographical distribution and plant community are closely related to diversity of the herbivore community. Future work is needed to investigate the likelihood that specialist herbivores become relatively more abundant in the forest as oaks are succeeded by hornbeams.  相似文献   

18.
The Middle America is located in the Nearctic–Neotropical boundary. The combination of temperate and tropical biota of these two biogeographic regions, plus an area of biotic overlap propitiates unusually high species diversity and endemism. We present the first general assessment based on the IUCN Red List of Threatened Species that provides evidence of widespread decline in the conservation status of land mammals from southern U.S.A. to Panama. One in every three species considered in our study (n = 273) is classified as threatened, and the rate of biodiversity loss increased 0.64% between 2008 and 2012. Endangered species of the Middle America represents 11.8% of the global endangered mammal species, and 7.9% of the threatened species. Habitat loss and the introduction of alien species are the major threats; however, the relative impact of these threats varies among habitats. For continental species, habitat loss is prevalent, while for insular species the introduction of alien species has devastating effects. Our results suggest that if no integral multi-species conservation actions are applied in the short-term, more than 20% of the extant mammal species in the region could become extinct in the near future (10–50 years).  相似文献   

19.
Cretaceous carbonate successions of the Bangestan Group, such as the Sarvak and Ilam formations, are among the most prolific hydrocarbon reserves of the Middle East. However, relatively little is known about their detailed palaeontology and biostratigraphy. Moreover, due to lithological similarity of these carbonate formations recognition of their boundaries in subsurface studies is problematic. To investigate these units, biostratigraphic analyses were carried out on nearly 1100 m of cores, including core plug samples and thin sections prepared from five giant and supergiant oilfields in the northern and southern Dezful Embayment, SW Iran. Accordingly, 59 species of foraminifera (assigned to 43 genera) as well as 11 species of non-foraminifera (10 genera) were recognized. As a result, three biozones were identified, which in stratigraphic order are: Nezzazata-Alveolinids Assemblage Zone; Moncharmontia apenninica-Nezzazatinella-Dicyclina Assemblage Zone; and Rotalia skourensis-algae Assemblage Zone. These are compared with the Wynd's (1965) biozonation scheme, previously introduced in the Zagros area, and a revised scheme is presented. Accordingly, a Cenomanian–Turonian age and a Coniacian–Campanian age are envisaged for the Upper Sarvak and Ilam formations, respectively. In our new biostratigraphic scheme, the Sarvak–Ilam formations boundary is considered to be located above the Moncharmontia apenninica-Nezzazatinella-Dicyclina Assemblage Zone (equivalent of Valvulammina-Dicyclina Assemblage Zone of Wynd, 1965), that is Turonian in age. This zone is bounded by two palaeoexposure surfaces, which correspond approximately to the C–T boundary transitional interval and a post-Turonian, which can be possibly assigned to the Coniacian. Significant sedimentological features of these disconformities include bauxitic–lateritic horizons, karstified profiles and solution-collapsed breccias. Geochemical signatures of these meteorically altered surfaces are also considered to calibrate biofacies and biozones. Finally, we compared our new biozonation scheme with other studies in neighboring areas of SW Iran and the Middle East.  相似文献   

20.
Two metrically defined subspecies have traditionally been recognised within the Palaearctic distribution range of the Egyptian fruit bat Rousettus aegyptiacus; the larger R. a. aegyptiacus in Egypt and the northern part of the Middle East and the smaller R. a. arabicus in the southern Middle East. An extensive material of R. aegyptiacus from all parts of this area, i.e. the Levant (incl. Turkey and Cyprus), Egypt (incl. Sinai), northern Sudan, Yemen, Oman, Iran, and Pakistan, as well as comparative samples from its sub-Saharan range, were tested using both morphological and genetic approaches in order to revise the species’ taxonomic status. The results indicated two possible processes, depending on the method used. Genetic analysis of the mitochondrial genome (nd1 and cytb) indicated low variation (< 2.0% of genetic distance) and lack of geographical structure while morphometric analysis indicated significant metric differences. Two basic size morphotypes were found within the Palaearctic range, with a rather mosaic-like geographical distribution and a lack of clear size distinction between the two categories, though intermediate types were detected. Thus, we suggest that all Palaearctic populations of R. aegyptiacus represent one form, the nominotypical subspecies, which is uniform in genetic traits but plastic in metric traits.  相似文献   

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