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1.
Tunisian hares (n = 45), currently assigned to Lepus capensis, were assayed for allelic variation at 40 allozyme loci, and allele frequencies at 32 loci were directly compared with earlier data of South African cape hares (L. capensis, n = 9) and European brown hares (L. europaeus, n = 244) to reveal genetic relationships among them. European mountain hares (L. timidus, n = 200) were used for outgroup comparison. In the Tunisian hares 27.5% of the loci were polymorphic with 2–4 alleles. Among all alleles at polymorphic loci, 15.1% occurred exclusively in Tunisian hares, 5.7% exclusively in cape hares, and 7.5% exclusively in brown hares at low frequencies. Not a single locus showed alternately fixed alleles between the samples of the L. capensis/L. europaeus complex. Levels of absolute and relative genetic differentiation among the samples of the L. capensis/ L. europaeus complex were low, relative to pairwise comparisons involving mountain hares. Diverse cluster analyses and multidimensional scaling of various pairwise genetic distance matrices concordantly grouped Tunisian hares with brown hares, and South African cape hares clustered only slightly farther apart, whereas mountain hares were distinctly separate. These results suggest regionally distinct phylogenetic units within an overall cohesive gene pool in the L. capensis/ L. europaeus complex, supporting Petter's view that all North African hares belong to L. capensis except for one local population of savanna hares, and that cape hares and brown hares are conspecific.  相似文献   

2.
A study on the inter- and intraspecies variation of MC1R gene was performed in Lepus species inhabiting the Mediterranean basin (L. granatansis, L. europaeus, L. corsicanus, L. castroviejoi and L. mediterraneus) and their neighboring species in Europe (L. timidus) and Africa (L. saxatilis, L. capensis), in order to infer micro- versus macroevolutionary adaptation. Eleven different sequences were isolated that corresponded to five amino acid sequences. Comparison of MC1R nucleotide phylogenetic tree with phylogenies resulting from mtDNA regions of the same species showed absence of congruence between these sets of markers. The Mediterranean area that offered refugia during last glaciation retains more MC1R genotypes compared with populations of North and Central Europe as a consequence of founder effects. L. corsicanus and L. castroviejoi bore identical alleles supportive of their conspecificity, as indicated by other molecular markers. Within L. europaeus, a group of Israeli hares were distinguished by a different MC1R functional allele; additional differences in coat colour and other genetic markers raise doubts about its taxonomic status. Finally, the present data reinforced the idea of bi-directional introgressive hybridization between L. europaeus and L. timidus in Switzerland.  相似文献   

3.
North African hares are currently considered belonging to cape hares (Lepus capensis), except for an isolated occurrence of L. victoriae in NW Algeria. However, the few existing molecular data are not unequivocal. Here, we study sequence variation (415 bp) in the hypervariable domain-1 of the mitochondrial (mt) control region, of hares with different coat colour from north-central Tunisia and NW Egypt, to test Petter's [(1959): Eléments d’une révision des Lièvres africains du sous-genre Lepus. Mammalia 23, 41–67] hypothesis that North African hares belong to L. capensis. Seven Tunisian and one Egyptian haplotypes were revealed from 28 hares and compared phylogenetically to 245 haplotypes of various Lepus species downloaded from GenBank. Neighbour joining (NJ) and principal coordinate (PCO) analyses based on a Tamura-Nei 93 distance matrix, as well as maximum parsimony (MP) analysis concordantly grouped all currently obtained haplotypes together into one monophyletic clade, and revealed relatively close relationships to the clades of African scrub hares (L. saxatilis) and brown hares (L. europaeus). The three distinguished coat colour types of Tunisian hares were paralleled only to a small extent by sequence differentiation. Haplotypes of L. capensis from the nominal Cape province of South Africa, North Africa, and China clustered into different major clades, respectively, with Chinese L. capensis haplotypes forming only a subclade within a major clade that encompassed predominantly “mountain/arctic hare-type sequences” in addition to sequences of several other palaearctic and nearctic species. One further Chinese L. capensis haplotype clustered into the L. comus clade. These results indicated occurrence of introgression and/or shared ancestral polymorphism. Such an evolutionary scenario implies using nucelar markers in addition to mtDNA for phylogenetic inferences in the genus Lepus; nevertheless, mtDNA is still useful for inferring phylogenetic history and biogeography of hares.  相似文献   

4.
Both the Cytb gene of mtDNA and Y chromosome markers were studied in a relatively large sample of brown hares (L. europaeus) from Europe and Anatolia (Turkey and Israel), together with other seven Lepus species, in order to enable comparative analysis of possible sex-specific gene flow. Furthermore, Y chromosome markers were compared with data from biparentally inherited markers in an attempt to understand whether or not their pattern of distribution was congruent with that of allozymes or whether they rather matched mtDNA phylogenies, with which they share uniparental inheritance. Consistent with the general observation, levels of interspecific genetic variability were very low for the Y chromosome markers compared with mtDNA. Moreover, lack of interspecific variation for the Y-DNA studied within Lepus genus rendered these markers improper for any further phylogenetic analysis. With the highest nucleotide diversity in Anatolia compared with Europe, both marker systems confirmed an unbroken species history in Anatolia, corroborated the hypothesis of continuous gene flow from Anatolia's neighbouring regions, and supported the idea of a quick postglacial colonization followed by expansion of the species in large parts of Europe. Phylogenetic analysis under mtDNA revealed the existence of four different haplogroups with a well defined distribution across Europe and Anatolia. Both genetic systems supported the deep separation of Anatolian and European lineages of L. europaeus. Nevertheless, Anatolian Y-DNA lineages extended across a longer geographic distance in south-eastern Europe than Anatolian mtDNA haplotypes, probably as a result of higher female philopatry that makes mtDNA introgression more difficult in brown hares.  相似文献   

5.
The Italian hare, Lepus corsicanus, was first described in Corsica more than 100 years ago, but the knowledge on the status of the species in this island remains scarce. Moreover, frequent introductions of thousands of individuals from other hare species, namely Lepus europaeus and Lepus granatensis, into Corsica are known to have occurred and an updated assessment of the prevalence of L. corsicanus in Corsica is therefore of utmost importance. Here, to estimate the relative prevalence of the hare species present in Corsica, we conducted a molecular analysis on 67 samples collected by hunters between 2002 and 2007 in 36 Corsican communes. Sequencing of portions of the nuclear gene transferrin and of the control region of the mitochondrial DNA allowed classifying most of the collected samples as belonging to L. corsicanus (70.1%). Of the sampled Corsican communes, 86.1% contained this species, while only in 11.1%, L. europaeus was present. Three of the analyzed specimens showed an inconsistent molecular assignment between markers suggesting a hybrid origin: L. corsicanus × L. europaeus, L. corsicanus × L. granatensis, and L. europaeus × L. granatensis. The first two cases of hybridization had never been described in nature, even in studies focusing on hares from Italy where L. corsicanus and L. europaeus are often sympatric. These results stress the real risk of corrosion of the native gene pool of L. corsicanus via hybridization with introduced species. We highlight the need of urgently rethinking the management plan of hare populations in Corsica.  相似文献   

6.
Among the European fauna, the Sardinian hare (Lepus sp.) is peculiar in that it differs from all other hares inhabiting the continent. Here, we report on the variation of a 461 bp sequence of hypervariable domain 1 of the mitochondrial control region, examined in 42 hares collected throughout Sardinia and compared to the corresponding sequences of different Lepus taxa. Seventeen novel haplotypes were found in the Sardinian population, resulting in a haplotype diversity of 0.840 and a nucleotide diversity of 0.012. As a result of Bayesian and principal coordinates analyses, Sardinian hares were grouped with North African hares, constituting a monophyletic clade that diverges from all other Old World hares, including Cape hares from South Africa and East Asia. Hence, our data agree that populations inhabiting North Africa and Sardinia form a distinct taxon, which could possibly be included in the L. capensis superspecies. Moreover, two corresponding lineages can be found in Sardinia and Tunisia, providing evidence of a common origin of the two populations and thus supporting the hypothesis that North African hares were introduced into the island in historical times. Our data show that the two lineages differ in their geographic distribution throughout the island and that the wild Sardinian population also shows the signature of a postintroduction demographic expansion.  相似文献   

7.
The brown hareLepus europaeus Pallas, 1778 occurs naturally in central Eurasia, but has been introduced to parts of northern Europe, South- and North America, Australia and New Zealand. Brown hares were introduced to Sweden from central Europe for hunting purposes during the 19th century. We investigated how the human--mediated brown hare colonisation of Sweden is reflected in the amount of genetic variation present by assessing variation and composition of mitochondrial DNA (mtDNA) lineages among Swedish brown hares. MtDNA from a total of 40 brown hare specimens from 15 localities were analysed for Restriction Fragment Length Polymorphisms. The haplotype diversity is surprisingly high (0.893 ± 0.002) when compared to the mtDNA diversity among brown hares on the European continent as well as to other mammalian species. Admixture of haplotypes from different source populations combined with a reduced effect of random genetic drift and a relaxed selection pressure due to rapid population growth after introduction are mechanisms that are likely to account for the observed high mtDNA haplotype diversity.  相似文献   

8.
Native red deer (Cervus elaphus) in Western Europe might at least partially derive from refugial populations which survived in the Iberian Peninsula during the last glacial maximum, and that expanded northwards at the onset of the Holocene. However, the phylogeny and genetic structure of red deer populations in the Iberian Peninsula are still poorly known. This study was planned, in a first step, to reconstruct the phylogenetic relationship of the main red deer populations extant in Spain by the analyses of an extensive sample of mitochondrial DNA sequences. Results indicate that sequences from these populations can be assigned to one of two deeply divergent mtDNA lineages (South-Western and Central-Eastern) with molecular divergence nearby the 2 %. In each lineage were respectively found sixteen and thirteen different haplotypes. It was evidenced that they may be allopatrically distributed in Spain with 86.6 % sequences of the South-Western lineage at the South-Western side and the 65 % sequences of Central-Eastern lineage in the Central-Eastern side. These mitochondrial lineages might have originated in two distinct refugial populations during the last glacial maximum. Genetic data also reveal instances of admixture between native populations and translocated European red deer, which belong to at least three distinct subspecies. Gene introgression was mainly due to red deer from Western European populations. The genetic contribution of red deer translocated from Eastern Europe (C. e. hippelaphus) or North Africa (C. e. corsicanus, C. e. barbarus) was apparently less deep. The extant phylogenetic relationship and evidences of genetic admixture suggest that sound conservation actions for the native Iberian red deer should severely restrict the introduction of alien red deer and, when possible, avoid admixture between the South-Western and Central-Eastern mtDNA lineages.  相似文献   

9.
Mitochondrial DNA (mtDNA) nucleotide sequences of African origin are found in various European populations at a low frequency (on average, less than 1%). Data on mtDNA variation in Eurasian and African populations have been analyzed, and African mtDNA lineages have been found in Europeans. It has been demonstrated that, despite the high diversity of mtDNA haplotypes of African origin in Europeans, few monophyletic clusters of African lineages are characterized by long-term diversity formed in Europe. Only two such mtDNA clusters (from haplogroups L1b and L3b) have been found, their evolutionary age not exceeding 6500 years. European and African populations have been compared with respect to the frequency distributions of the alleles of autosomal microsatellite loci found in Russian carriers of African mtDNA haplotypes. It has been demonstrated that alleles typical of Europeans are characteristic of the autosomal genotypes of these Russian individuals.  相似文献   

10.
Information on reproductive biology of the European hare (Lepus europaeus) in different environmental and landscape conditions comprises part of fundamental knowledge regarding species’ adaptive responses as well as many aspects of its biology. Most of the studies conducted on European hare reproduction are confined to midlatitude and northern populations, whereas no data exist on the indigenous southern populations. Here, we present information on reproductive characteristics of European hares inhabiting Mediterranean ecosystems on the island of Crete, Greece for two successive hunting seasons. Although the annual reproductive cycle of the species is well known, with an autumn sexual inactivity, the duration of this period is subjected to fluctuations in different years and for different areas. According to our data, hare populations of Crete present an autumn–early winter reproductive activity with high proportions of pregnant females observed in all the months of the study. Furthermore, the estimated mean litter size (1.54 SE ± 0.07) while signed to the lowest values ever observed for European hares is similar to values obtained in continuous breeding species of the same genus, Lepus granatensis, Lepus corsicanus, Lepus (capensis) mediterraneus, and Lepus capensis also inhabiting warm climates. In conclusion, our results suggest that Cretan European hare populations exhibit a reproductively active period during autumn–early winter where proportions of pregnant females and litter size give a strong indication of a continuous reproduction throughout the year.  相似文献   

11.
Apis mellifera is composed of three evolutionary branches including mainly African (branch A), western and northern European (branch M), and southeastern European (branch C) populations. The existence of morphological clines extending from the equator to the Polar Circle through Morocco and Spain raised the hypothesis that the branch M originated in Africa. Mitochondrial DNA analysis revealed that branches A and M were characterized by highly diverged lineages implying very remote links between both branches. It also revealed that mtDNA haplotypes from lineages A coexisted with haplotypes M in the Iberian Peninsula and formed a south-north frequency cline, suggesting that this area could be a secondary contact zone between the two branches. By analyzing 11 populations sampled along a France-Spain/Portugal-Morocco-Guinea transect at 8 microsatellite loci and the DraI RFLP of the COI-COII mtDNA marker, we show that Iberian populations do not present any trace of “africanization” and are very similar to French populations when considering microsatellite markers. Therefore, the Iberian Peninsula is not a transition area. The higher haplotype A variability observed in Spanish and Portuguese samples compared to that found in Africa is explained by a higher mutation rate and multiple and recent introductions. Selection appears to be the best explanation to the morphological and allozymic clines and to the diffusion and maintenance of African haplotypes in Spain and Portugal.  相似文献   

12.
Systematics and taxonomy of hares of the genus Lepus (Lagomorpha) are under contentious debate, and phylogenetic relationships among many taxa are not well understood. Here we study genetic differentiation and evolutionary relationships among North African hares, currently considered subspecies of Lepus capensis , cape hares ( L. capensis ) from the Cape province in South Africa, and brown hares ( L. europeaus ) from Europe and Anatolia, using maternally (mtDNA) and biparentally (allozymes) inherited markers. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of a c. 1.8 kb long segment of the mitochondrial control region using eight hexanucleotide-recognizing restriction endonucleases yielded 28 haplotypes, and horizontal starch gel electrophoresis of proteins encoded by 25 structural gene loci revealed 52 alleles at 18 polymorphic loci. Diverse phylogenetic analyses (neighbor joining dendrogram, median joining network, multidimensional scaling of pairwise distances, AMOVA, F -statistics, hierarchical F -statistics) of genetic variants revealed marked substructuring of mtDNA into three phylogeographic groups, namely an African, a central European, and an Anatolian, but a somewhat less pronounced overall differentiation of the nuclear genome, despite a relatively high number of population-specific (private) alleles. However, all our results are not incongruent with Petter's (1959: Mammalia 23 , 41; 1961: Z. f. Säugetierkunde 26 , 30; 1972 : Société Des Sciences Naturelles et Physiques du Maroc 52 , 122) hypothesis that North African hares generally belong to L. capensis and that brown hares should be included in this species as well.  相似文献   

13.
A previous study on the evolutionary patterns of Tarentola mauritanica demonstrated that low levels of mitochondrial diversity observed in the European populations relative to nuclear markers were consistent with a selective sweep hypothesis. In order to unravel the mitochondrial evolutionary history in this European population and two other lineages of T. mauritanica (Iberian and North African clades), variation within 22 nearly complete mitogenomes was analyzed. Surprisingly, each clade seems to have a distinct evolutionary history; with both the European and Iberian clades presenting a decrease of polymorphism, which in the former is consistent with departure from neutrality of the mtDNA (positive or background selection), but in the latter seems to be the result of a bottleneck after a population expansion. The pattern exhibited by the North African clade seems to be a consequence of adaptation to certain mtDNA variants by positive selection.  相似文献   

14.
15.
Although only of medium size, and thus of little nutritional value compared to big game such as mammoths and ungulates, hares (Lepus spp.) probably have always been a food source for humans, as documented in archaeological finds. Nowadays, hares, particularly such species as the brown hare (L. europaeus), are among the most important game species in many European countries. For hunting, perhaps religious reasons, and in connection with certain myths, hares have been and are still being intentionally translocated. Ancient translocations by humans can be inferred from the presence of hares on islands that had no mainland connections, at least during the Pleistocene, the major evolutionary period of the genus Lepus. We review some of the literature on anthropogenic translocations of hares. We focus on three examples [the brown hare (L. europaeus), the Corsican hare (L. corsicanus), and the Sardinian hare (L. capensis)], where some molecular data could be used to trace the translocation routes and possible origins of introduced hare populations. Certain molecular marker systems, such as sequences of the hypervariable part I (HV-1) of the mitochondrial control region, show high variability in hare species and are thus promising for tracing both recent and ancient origins of translocated hares. Some other molecular marker systems as well as caveats connected with the use of such marker systems in the genus Lepus are also discussed.  相似文献   

16.
Genetic introgression from a resident species into an invading close relative can result from repeated hybridisation along the invasion front and/or allele surfing on the expansion wave. Cases where the phenomenon is massive and systematic, such as for hares (genus Lepus) in Iberia, would be best explained by recurrent hybridisation but this is difficult to prove because the donor populations are generally extinct. In the Pyrenean foothills, Lepus europaeus presumably replaced Lepus granatensis recently and the present species border is parallel to the direction of invasion, so that populations of L. granatensis in the contact zone represent proxies of existing variation before the invasion. Among three pairs of populations sampled across this border, we find less differentiation of mitochondrial DNA (mtDNA) across than along it, as predicted under recurrent hybridisation at the invasion front. Using autosomal microsatellite loci and X- and Y-linked diagnostic loci, we show that admixture across the border is quasi-absent, making it unlikely that lack of interspecific mtDNA differentiation results from ongoing gene flow. Furthermore, we find that the local species ranges are climatically contrasted, making it also unlikely that ongoing ecology-driven movement of the contact account for mtDNA introgression. The lack of mtDNA differentiation across the boundary is mostly due to sharing of mtDNA from a boreal species currently extinct in Iberia (Lepus timidus) whose mitochondria have thus remained in place since the last deglaciation despite successive invasions by two other species. Home-loving mitochondria thus witness past species distribution rather than ongoing exchanges across stabilised contact zones.  相似文献   

17.
The taxonomic positions ofRetzia, Desfontainia, andNicodemia have been much discussed, and all three genera have been included inLoganiaceae (Gentianales). We have made a cladistic analysis ofrbcL gene sequences to determine the relationships of these taxa toGentianales. Four newrbcL sequences are presented; i.e., ofRetzia, Desfontainia, Diervilla (Caprifoliaceae), andEuthystachys (Stilbaceae). Our results show thatRetzia, Desfontainia, andNicodemia are not closely related toLoganiaceae or theGentianales. Retzia is most closely related toEuthystachys and is better included inStilbaceae. The positions ofDesfontainia andNicodemia are not settled, butDesfontainia shows affinity for theDipsacales s.l. andNicodemia for theLamiales s.l.  相似文献   

18.
Hares (Lepus capensis Linnaeus 1758) were probably introduced into Sardinia in historical times. Previous studies indicated North Africa as the most likely source area but did not exclude the occurrence of hybridization events with continental brown hares (L. europaeus Pallas 1778) perhaps introduced for hunting purposes. We implemented both morphometric and genetic approaches to verify the genetic isolation of the Sardinian population. Specifically, we conducted a multivariate analysis of craniometric data and analysed 461 bp of the mitochondrial control region and 12 autosomal microsatellites in Sardinian hares, using North African cape hares and European brown hares as reference populations. Sardinian hares displayed a peculiar skull shape. In agreement, both nuclear and mitochondrial markers remarked the distinctiveness of this population. Observed and expected heterozygosity were 0.52 and 0.61, while haplotype and nucleotide diversity were 0.822 and 0.0129. Self‐assignment based on Bayesian cluster analysis was high (average membership 0.98), and no evident signs of introgression from continental brown hares were found. Our results support the hypothesis that the Sardinian hares have been introduced from North Africa, remained genetically isolated since the founding event and evolved independently from the source population. This long‐lasting isolation and the consequent genetic drift resulted in a differentiation, perhaps accompanied by an adaptation to local environmental conditions.  相似文献   

19.
In many areas, the management of overexploited populations of brown hare (Lepus europaeus) is based on annual restocking. While in some cases exotic hares are introduced, in some others hares are captured locally within protected areas and subsequently released into hunting grounds. We evaluated the genetic effects of this management regime in an Italian province where the brown hare population has recovered in the last few decades, by sequencing the hypervariable domain 1 of the mitochondrial control region and by genotyping eight autosomal microsatellites in hares sampled in both hunting and non-hunting areas. Both nuclear (H e?=?0.68 and H o?=?0.65) and mitochondrial variability (h?=?0.853 and π?=?0.012) were in line with other European populations. When comparing our data with mitochondrial sequences retrieved from GenBank, out of the 21 detected haplotypes, 14 were private to our study area. While 4.6 % of the individuals were found to carry haplotypes attributable to past introductions, 41.5 % grouped within a well-supported lineage, previously identified with a presumed native Italian taxon, L. e. meridiei. Despite the detectable geographic partitioning of mitochondrial haplotypes across the province, no genetic structure resulted from microsatellites analysis, indicating that no reproductive barriers exist among hares carrying different mitochondrial lineages. In conclusion, the local management seems to have contributed to the recovery of the species and to a full admixture of nuclear genes in the province. However, neither the extensive translocations nor the possible introductions of exotic heads seem to have completely undermined the local mitochondrial lineages.  相似文献   

20.
Schimperella is a small African genus related toRhynchostegium. It is characterized by noncomplanate plants with erect capsules and reduced endostomes. Two species are recognized:S. katalensis andS. rhynchostegioides. A proposed synonym ofS. rhynchostegioides, Rhynchostegium nervosum, is best placed inIsothecium, asIsothecium nervosum.  相似文献   

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