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1.
    
The isolation and characterization of six polymorphic loci from a Testudo hermanni genomic library is reported. Enrichment was performed for AC but four of the characterized microsatellites present also an additional motif. Variability was tested on populations of the two recognized subspecies, Testudo hermanni hermanni and Testudo hermanni boettgeri. For one locus, a size range specific for the subspecies T. h. hermanni was observed. These are the first primers identified directly in the genome of T. hermanni  相似文献   

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We report here development and characterization of 48 novel microsatellite markers for Ropalidia marginata, a tropical, primitively eusocial polistine wasp from peninsular India. Thirty‐two microsatellites showed polymorphism in a wild population of R. marginata (N = 38) collected from Bangalore, India. These markers will facilitate answering some interesting questions in ecology and evolutionary biology of this wasp, such as population structure, serial polygyny, intra‐colony genetic relatedness and the pattern of queen succession.  相似文献   

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Testudo marginata, the largest European land tortoise, is suffering habitat degradation and destruction. Some populations, in markedly degraded habitats, are characterized by divergent morphotypes. However, the evolutionary significance of these morphotypes is of debate. Using 11 polymorphic microsatellites, we studied: (1) marginated tortoises from Sardinia that display a divergent morphotype – this population was potentially introduced from Greece; and (2) an area in the southern Peloponnese that includes a small and degraded zone in which marginated tortoises are dwarf. Genetic analyses run without any a priori assignment clearly acknowledge the specimens sampled in the territory of the dwarf form as a single group whilst Sardinian specimens are clustered with other specimens from the northern part of the area sampled in Greece. Demographic analyses suggest that Sardinian tortoises originated recently from some of the populations sampled in the northern part of the area sampled in Greece. Over locations sampled in Greece, a landscape‐genetic analysis allowed us to detect potential landscape features that may reduce gene flow between the dwarf form territory and surrounding areas. Our results suggest that the territory of the dwarf form is particularly propitious for marginated tortoises and that conservation regulations in Greece should be reinforced to protect this area from increasing impact of human activities changing from traditional agriculture to mechanization and extensive use of chemicals. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 591–606.  相似文献   

5.
The courtship and mounting behavior of promiscuous tortoisesis based on a multiple signaling system that includes visual,olfactory, tactile, and acoustic signals. Vocalizations relatedto mounting seem to be particularly intriguing because tortoisesvocalize mainly at this time. Vocalizations and courtship behaviormight be costly for males, and if these costs increase differentiallyfor different males, then the potential exists for vocalizationsand displays to reveal male individual quality on which femalescould base their mate choice. In the present study, by usingindividuals breeding in seminatural enclosures, we experimentallyinvestigated whether the mounting call of male Hermann's tortoises(Testudo hermanni) represents a relevant stimulus to both malesand females. We also looked for potential preference towarddifferent acoustic stimuli in order to determine which callfeatures, if any, played a role in attracting potential partnersor deterring rivals. Females were sensitive to call playback,whereas males apparently paid little attention to playback.In addition, females showed a significant preference towardhigh-pitched calls emitted at high rate. Also, females exhibiteda strong tendency toward short-duration calls. Because callrate is related to hematocrit in Hermann's tortoise males, byresponding to fast-rate calls females are also choosing high-qualitypartners as sires of their offspring. This is the first studyin which an attractive function of tortoise vocalizations hasbeen documented.  相似文献   

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The radiated tortoise (Geochelone radiata) is an endangered endemic species from Madagascar that inhabits the semiarid spiny forest of the southern part of the island. Habitat destruction and illegal harvesting greatly threaten this species, as attested by the significant reduction of its distribution area in the past 30 years. In order to undertake appropriate conservation actions, it is essential to acquire a better knowledge of its genetic structure. For this study, 145 blood samples were collected from three populations of radiated tortoises in southwestern Madagascar. Eight microsatellite loci were found to be polymorphic, and allelic diversity and observed heterozygosity were high for all markers.  相似文献   

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Genetic tools have become a critical complement to traditional approaches for meeting short‐ and long‐term goals of ex situ conservation programs. The San Diego Zoo (SDZ) harbors a collection of wild‐born and captive‐born Galápagos giant tortoises (n = 22) of uncertain species designation and unknown genealogical relationships. Here, we used mitochondrial DNA haplotypic data and nuclear microsatellite genotypic data to identify the evolutionary lineage of wild‐born and captive‐born tortoises of unknown ancestry, to infer levels of relatedness among founders and captive‐born tortoises, and assess putative pedigree relationships assigned by the SDZ studbook. Assignment tests revealed that 12 wild‐born and five captive‐born tortoises represent five different species from Isabela Island and one species from Santa Cruz Island, only five of which were consistent with current studbook designations. Three wild‐born and one captive‐born tortoise were of mixed ancestry. In addition, kinship analyses revealed two significant first‐order relationship pairs between wild‐born and captive‐born tortoises, four second‐order relationships (half‐sibling) between wild‐born and captive tortoises (full‐sibs or parent‐offspring), and one second‐order relationship between two captive‐born tortoises. Of particular note, we also reconstructed a first‐order relationship between two wild‐born individuals, violating the founder assumption. Overall, our results contribute to a worldwide effort in identifying genetically important Galápagos tortoises currently in captivity while revealing closely related founders, reconstructing genealogical relationships, and providing detailed management recommendations for the SDZ tortoises. Zoo Biol 31:107;–120, 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

10.
We describe primers and polymerase chain reaction (PCR) conditions to amplify 14 tri- and tetranucleotide microsatellite loci for the Mojave desert tortoise (Gopherus agassizii). Across three populations (87 individuals) located in the Mojave Desert, USA, the markers yielded a range of four to 33 alleles and an average observed heterozygosity of 0.733 (range 0.433 to 0.933). We neither detected linkage disequilibrium between any pair of loci nor did we find a consistent pattern of deviation from Hardy-Weinberg equilibrium. These microsatellites are designed for PCR multiplexing, and provide higher throughput capacity to aid in conservation genetics studies for this threatened species.  相似文献   

11.
The extinction of the giant tortoises of the Seychelles Archipelago has long been suspected but is not beyond doubt. A recent morphological study of the giant tortoises of the western Indian Ocean concluded that specimens of two native Seychelles species survive in captivity today alongside giant tortoises of Aldabra, which are numerous in zoos as well as in the wild. This claim has been controversial because some of the morphological characters used to identify these species, several measures of carapace morphology, are reputed to be quite sensitive to captive conditions. Nonetheless, the potential survival of giant tortoise species previously thought extinct presents an exciting scenario for conservation. We used mitochondrial DNA sequences and nuclear microsatellites to examine the validity of the rediscovered species of Seychelles giant tortoises. Our results indicate that the morphotypes suspected to represent Seychelles species do not show levels of variation and genetic structuring consistent with long periods of reproductive isolation. We found no variation in the mitochondrial control region among 55 individuals examined and no genetic structuring in eight microsatellite loci, pointing to the survival of just a single lineage of Indian Ocean tortoises.  相似文献   

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Animal populations have developed multiple strategies to deal with environmental change. Among them, the demographic buffering strategy consists in constraining the temporal variation of the vital rate(s) that most affect(s) the overall performance of the population. Tortoises are known to buffer their temporal variation in adult survival, which typically has the highest contribution to the population growth rate λ, at the expense of a high variability on reproductive rates, which contribute far less to λ. To identify the effects of projected increases in droughts in its natural habitat, we use field data collected across 15 locations of Testudo graeca in southeast Spain over a decade. We analyse the effects of environmental variables on reproduction rates. In addition, we couple the demographic and environmental data to parameterise an integral projection model to simulate the effects of different scenarios of drought recurrence on λ under different degrees of intensity in the survival–reproduction tradeoff. We find that droughts negatively affect the probability of laying eggs; however, the overall effects on λ under the current drought recurrence (one/decade) are negligible when survival is constant (independent of the reduction of reproduction by drought events) and when survival increased as a tradeoff with the reduction of reproduction rates, with a threshold to population viability at three or more droughts/decade. Additionally, we show that, although some species may buffer current environmental regimes by carefully orchestrating how their vital rates vary through time, a demographic buffering strategy is insufficient to ensure population viability in extreme regimes. Our findings support the hypothesis that the demographic buffering strategy has a limit of effectiveness when adverse conditions occur frequently. Our methodological approach provides a framework for ecologists to determine how effective the management of environmental drivers can be for demographically buffering populations, and which scenarios may not provide long-term population persistence.  相似文献   

13.
The Alyki wetland in northern Greece is a site of notable herpetological and ornithological importance. A large population of the tortoise Testudo hermanni began to recover slowly (r = 0.016) between 1990 and 1999, following catastrophic habitat destruction in 1980 and slow decline from 1980–1990. Heathland vegetation showed signs of desiccation, probably due to increased drainage by the salt works, including deterioration of Crataegus, Ruscus and Asphodelus, and loss of formerly important food plants of tortoises. Activity and body mass condition of tortoises were reduced in summer in grassy heath habitats. Predation of artificial (chicken egg) tortoise nests increased, and the relative frequency of juveniles (about 1 % of samples) was lower than after severe habitat destruction or pesticide damage. These changes were attributed to an increasing population of badgers, Meles meles. Population levels of waders were lower in 1998/1999 than in 1988/1989, especially avocets (Recurvirostra avosetta) for which the site was internationally important. Breeding populations of most waders and larids also declined. Mediterranean gulls, for which Alyki was formerly the most important breeding area outside Russia, did not nest from 1990 to 1998, and nests were unsuccessful in 1999. Changes in breeding populations were due to falling lagoon levels, exposure to predators and vegetation encroachment on islet breeding sites. Midwinter waterfowl populations remained high or increased, however, as alternative feeding areas were available in the lagoon. Preservation of the habitats against development of the salt works and increasing desiccation are necessary to maintain the long-term conservation value of the Alyki site.  相似文献   

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The tortoise Testudo hermanni is endangered by habitat fragmentation and loss in western Europe, where its high public profile and specific conservation projects make this a flagship species. Studies of movement in the peak reproductive season (June) showed that home ranges were substantially larger in France than in Greece. This difference was due to the intensity of use of the home range, not to the distance moved which was remarkably similar in the two areas. There was no sexual difference in home range area. The home range was therefore not large in France because of movement to nesting sites, but rather for utilization of the greater habitat complexity there. The need for reserves to include different vegetation types makes conservation of T. hermanni in France more difficult. Conversely, the need for large reserves increases its value as an umbrella species for conservation of biodiversity.  相似文献   

15.
An adult Egyptian tortoise (Testudo kleinmanni) presented with clinical signs of enteritis and died 5 weeks after initiation of antibiotic therapy. Histological examination of the small intestine revealed heavy infection with Cryptosporidium sp.; over 80% of epithelial cells harboured the pathogen. No Cryptosporidium developmental stages were present in the stomach or the lungs. The intestinal lamina propria and mucosa were infiltrated by heterophils, lymphocytes and macrophages. The present study constitutes the first report of Cryptosporidium sp. infection in T. kleinmanni, and the first histological documentation of intestinal cryptosporidiosis in Chelonia.  相似文献   

16.
The Indian Star tortoise (Geochelone elegans) belongs to the family Testunidae and is distributed in southwest India and Sri Lanka. In addition to facing loss of its natural habitat, the species is also illegally traded as food and as an exotic pet internationally. Here we report DNA-based analyses for identification and repatriation of these tortoises into their natural habitat. We have attempted to establish the geographical origin of these tortoises rescued from smugglers, by comparing the microsatellite and mitochondrial markers of rescued animals with animals of known provenance. Star tortoises exhibited strong genetic structure in India. The populations from western India were genetically distinct at microsatellite and mitochondrial loci from southern populations. The rescued individuals had similar multilocus genotypes and mitochondrial DNA haplotypes as the reference individuals from south India. However, the precise geographic origin of many of the rescued samples remains unresolved, because we could not assign them to southern populations and the Neighbor-Joining cluster analysis indicated that some of rescued tortoises formed distinct clusters. These data strongly suggest that the rescued group of tortoises is composed of a mix of individuals from differentiated source populations that are probably located in southern India and possibly Sri Lanka. Our study provides valuable information based on molecular markers for the assessment of genetic diversity in Indian Star tortoises.  相似文献   

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Assessing population trends is a basic prerequisite to carrying out adequate conservation strategies. Selecting an appropriate method to monitor animal populations can be challenging, particularly for low-detection species such as reptiles. This study compares 3 detection-corrected abundance methods (capture–recapture, distance sampling, and N-mixture) used to assess population size of the threatened Hermann's tortoise. We used a single dataset of 432 adult tortoise observations collected at 118 sampling sites in the Plaine des Maures, southeastern France. We also used a dataset of 520 tortoise observations based on radiotelemetry data collected from 10 adult females to estimate and model the availability (g0) needed for distance sampling. We evaluated bias for N-mixture and capture–recapture, by using simulations based on different values of detection probabilities. Finally, we conducted a power analysis to estimate the ability of the 3 methods to detect changes in Hermann's tortoise abundances. The abundance estimations we obtained using distance sampling and N-mixture models were respectively 1.75 and 2.19 times less than those obtained using the capture–recapture method. Our results indicated that g0 was influenced by temperature variations and can differ for the same temperature on different days. Simulations showed that the N-mixture models provide unstable estimations for species with detection probabilities <0.5, whereas capture–recapture estimations were unbiased. Power analysis showed that none of the 3 methods were precise enough to detect slow population changes. We recommend that great care should be taken when implementing monitoring designs for species with large variation in activity rates and low detection probabilities. Although N-mixture models are easy to implement, we would not recommend using them in situations where the detection probability is very low at the risk of providing biased estimates. Among the 3 methods allowing estimation of tortoise abundances, capture–recapture should be preferred to assess population trends. © 2013 The Wildlife Society.  相似文献   

18.
四爪陆龟血细胞形态学参数的初步研究   总被引:2,自引:1,他引:2       下载免费PDF全文
对四爪陆龟的血细胞进行了显微观察 ,并对红细胞和白细胞及其细胞核的大小和面积、血红蛋白含量以及红细胞渗透脆性等参数进行测量。结果表明 :( 1 )四爪陆龟红细胞含量平均值为 62 ( 5 2~ 83 )万个 mm3 血液 ;( 2 )红细胞的平均长度为 ( 1 6 70± 1 2 5 ) μm ,范围 1 5 60~ 1 7 5 2 μm ;( 3 )红细胞宽度为 ( 9 5 3± 0 92 ) μm ,范围 7 2 0~ 1 0 8μm ;( 4 )红细胞核长度为 ( 5 5 9± 0 5 9) μm ,范围 4 80~ 6 48μm ;( 5 )红细胞核宽度为 ( 3 65± 0 5 6) μm ,范围 2 64~ 4 5 6μm ;( 6)血红蛋白含量为 ( 7 3 0± 0 66)g 1 0 0ml血液 ( 6 5 0~8 5 0 ) ;( 7)红细胞渗透脆性 ,开始溶血浓度为 0 2 4%NaCl溶液 ,完全溶血浓度为 0 1 6%NaCl溶液 ;( 8)红细胞平均大小 (长径×短径 )为 ( 1 6 70× 9 5 3 ) μm2 ;( 9)白细胞平均值 0 5 6( 0 42~ 0 70 )万 mm3 ,其中嗜中性粒细胞大小为 ( 1 2 0 8± 1 86) μm ,嗜酸性粒细胞大小为 ( 9 2 5± 2 3 ) μm ,嗜碱性粒细胞大小为 ( 8 75±0 2 3 ) μm ,单核细胞大小为 ( 1 1 40± 1 0 6) μm ,淋巴细胞大小为 ( 7 5 0± 2 1 ) μm ,凝血细胞大小为 ( 4 2 0±1 40 ) μm。  相似文献   

19.
Sexual dimorphism of body size and shell shape in European tortoises   总被引:1,自引:0,他引:1  
Adult body size and shape were examined in almost 1400 individuals of the tortoises Testudo graeca , T. hermanni and T. marginata from Greece. The size at maturity was greater in females than in males in all three species. Maximum and mean adult sizes were also greater in females than in males in T. graeca and T. hermanni . Males grew to a larger size than females in T. marginata , and mean adult size was similar in the sexes in this species. Sexual dimorphism of shape (adjusted for size covariate) was shown in most of the characters examined, and the degree of this dimorphism differed significantly among the three species. Differences were related to their contrasting courtship behaviours: horizontal head movements and severe biting in T. marginata , vertical head bobs and carapace butting in T. graeca , and mounting and tail thrusting in T. hermanni . There was no difference in the frequency of observations of courtship or fighting among the three species, but courtship was about 10 times more common than combat in males. All species showed greatest courtship activity in autumn; copulation was rarely observed in T. hermanni (only 0.36% of courting males) and not seen in the other species in the field. Observations made throughout the activity season indicated that feeding was equally common in males and females in all three species. Differences in shape were more likely to be the result of sexual selection than of natural selection for fecundity. Detailed predictions are made for sexual dimorphism of other characters in these species.  相似文献   

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Herbivorous vertebrates rely on complex communities of mutualistic gut bacteria to facilitate the digestion of celluloses and hemicelluloses. Gut microbes are often convergent based on diet and gut morphology across a phylogenetically diverse group of mammals. However, little is known about microbial communities of herbivorous hindgut‐fermenting reptiles. Here, we investigate how factors at the individual level might constrain the composition of gut microbes in an obligate herbivorous reptile. Using multiplexed 16S rRNA gene sequencing, we characterized the faecal microbial community of a population of gopher tortoises (Gopherus polyphemus) and examined how age, genetic diversity, spatial structure and kinship influence differences among individuals. We recovered phylotypes associated with known cellulolytic function, including candidate phylum Termite Group 3, suggesting their importance for gopher tortoise digestion. Although host genetic structure did not explain variation in microbial composition and community structure, we found that fine‐scale spatial structure, inbreeding, degree of relatedness and possibly ontogeny shaped patterns of diversity in faecal microbiomes of gopher tortoises. Our findings corroborate widespread convergence of faecal‐associated microbes based on gut morphology and diet and demonstrate the role of spatial and demographic structure in driving differentiation of gut microbiota in natural populations.  相似文献   

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