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1.
We investigated genetic diversity and the mating system of the Norway lobster (Nephrops norvegicus) in a wild population off the Portuguese coast. Approximately 100 individuals were screened for 2 microsatellite loci. For 11 ovigerous lobsters both the female and a sample of her offspring (24 eggs) were genotyped. High genetic diversity was observed for the 2 markers in the population. Paternity within broods was analyzed by comparing multilocus genotypes of each egg with the corresponding mother, and the male parent contribution was then deduced. Multiple paternity was observed in 6 of the 11 broods studied. In those cases, 2 to 3 male parents were likely to have contributed to the fertilization of the eggs. When multiple paternity was involved, the comparative reproductive success of the male parents was quite even. This is the first report of multiple paternity in the Norway lobster. Comparisons with other taxa are presented, and consequences of multiple paternity are discussed.  相似文献   

2.
    
Microsatellite polymorphisms are playing an increasingly vital role in primatological research, and are particularly useful for paternity exclusion in both wild and captive populations. Although vervet monkeys (Chlorocebus aethiops) are commonly studied in both settings, few previous studies have utilized microsatellite markers for assessing genetic variation in this species. In a pilot project to assess paternity in the UCLA-VA Vervet Monkey Research Colony (VMRC), we screened 55 commercially available human microsatellite markers chosen from a panel of 370 that have been shown to be polymorphic in baboons (Papio hamadryas). Using a standard PCR protocol, 43 (78%) loci produced amplifiable product. Of these, 14 were polymorphic and 11 were genotyped in 51 individuals, including 19 offspring and 14 potential sires. The average heterozygosity across the 11 loci was.719. In all 19 paternity cases all but one male was excluded as the true sire at two or more loci. This includes successfully distinguishing between two maternal half-sib brothers who were potential sires in most of the paternity cases. Given that the colony is descended from 54 wild-caught founders trapped between 1975 and 1987 from an introduced population on St. Kitts, West Indies, these values imply high microsatellite variability in natural vervet populations. Our results provide a panel of markers derived from the human genome that is suitable for assessing genetic variation and paternity in vervets.  相似文献   

3.
Genetic analysis reveals promiscuity among female cheetahs   总被引:2,自引:0,他引:2  
Cheetahs (Acinonyx jubatus) have a combination of ranging patterns and social system that is unique in mammals, whereby male coalitions occupy small territories less than 10% of the home range of solitary females. This study uses non-invasive genetic sampling of a long-term study population of cheetah in the Serengeti National Park in Tanzania to infer the mating system. Individual cheetah genotypes at up to 13 microsatellite loci were obtained from 171 faecal samples. A statistical method was adapted to partition the cubs within each litter (n=47) into full-sibling clusters and to infer the father of each cluster using these loci. Our data showed a high rate of multiple paternity in the population; 43% of litters with more than one cub were fathered by more than one male. The results also demonstrated that female fidelity was low, and provided some evidence that females chose to mate with unrelated males within an oestrus cycle. The low rate of paternity assignments indicated that males living outside the study area contributed substantially to the reproduction of the cheetah population.  相似文献   

4.
Microsatellites were employed to estimate frequency of multiple paternity litters of two species of mice (genus Apodemus): striped field mouse (A. agrarius), and wood mouse (A. sylvaticus). Ten pregnant females of A. agrarius and six of A. sylvaticus were collected from natural populations in the northern Ukraine and analysed with 11 and nine microsatellite loci, respectively. Multiple paternity was indicated in eight of 10 litters in A. agrarius and in three of six litters in A. sylvaticus. Multiple paternity was documented at several loci (ranging from two to 10). In two cases (A. agrarius), three males were estimated to have fathered the litter.  相似文献   

5.
Five polymorphic microsatellite loci were isolated from the Australian smelt, Retropinna semoni, in order to study levels of connectivity among populations at various spatial scales. Screening of one natural population (n = 30) from central Victoria, southeastern Australia, yielded nine to 14 alleles per locus with observed levels of heterozygosity ranging from 0.40 to 0.80. All loci were in Hardy–Weinberg equilibrium after Bonferroni correction for multiple tests. These loci should provide a useful tool in further understanding the population genetics of this species.  相似文献   

6.
    
In mating systems with sperm competition, paternity is frequently established with modern DNA techniques. These methods are often expensive and cumbersome, and can be especially difficult for highly fecund species. An additional objective of many paternity studies is to discover the relationship between sperm number and paternity. We present here a competitive polymerase chain reaction (PCR) protocol, coupled with the use of an automated sequencer, that has two functions: (i) to measure directly relative sperm output of males in sperm competition; and (ii) to estimate paternity distributions of large numbers of offspring simultaneously. Our technique was calibrated using a microsatellite locus of the bluehead wrasse, Thalassoma bifasciatum, with the result that product ratio after competitive PCR accurately reflected the initial template proportions of known mixtures of DNA. When we applied our technique to multiple larvae of separate mating events we found that paternity distributions estimated with the competitive PCR technique closely matched the estimates derived from the traditional method of pooling paternity data from individual larvae. Finally, we compared paternity of these spawns with relative sperm contribution estimates. This comparison suggests that ejaculate size alone does not predict a male's proportion of paternity within the group.  相似文献   

7.
    
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8.
Genetic variation at four microsatellite loci in conjunction with that at a highly variable allozyme locus was used to analyse paternity over a 12-year period in 13 social groups of toque macaques Macaca sinica inhabiting a natural forest in Polonnaruwa, Sri Lanka. Paternity exclusion analysis revealed that the set of offspring produced by a female usually consists of half-siblings because few males father more than one offspring with a particular female. No evidence of offspring produced by matings between first degree relatives was found. The social unit in toque macaques was not identical to the reproductive unit and the possibility of paternity by males outside the social group should be considered when estimating male reproductive output. Although it was common for multiple males to father offspring in a social group each year, reproduction within a group during a breeding season tended to be limited to a few males. The mean number of males reproducing per group per year was independent of the number of males in a group. The paternity data suggests that many males may father relatively few offspring during their entire lives and that the effective population size for toque macaques may be much smaller than indicated by demographic data.  相似文献   

9.
  总被引:2,自引:0,他引:2  
Highly variable microsatellite loci were used to study the mating system of Nerophis ophidion, a species of pipefish in which pregnant males carry embryos on the outside of their body rather than in an enclosed brood pouch. Despite this mode of external fertilization and brooding, otherwise rare in the family Syngnathidae, the genotypes of all embryos proved to be consistent with paternity by the tending male, thus indicating that cuckoldry by sneaker males is rare or nonexistent in this species. N. ophidion is a phylogenetic outlier within the Syngnathidae and its reproductive morphology is thought to be close to the presumed ancestral condition for pipefishes and seahorses. Thus, our genetic results suggest that the evolutionary elaboration of the enclosed brood pouch elsewhere in the family was probably not in response to selection pressures on pregnant males to avoid fertilization thievery. With regard to maternity assignments, our genotypic data are consistent with behavioural observations indicating that females sometimes mate with more than one male during a breeding episode, and that each male carries eggs from a single female. Thus, the polyandrous genetic mating system in this species parallels the social mating system, and both are consistent with a more intense sexual selection operating on females, and the elaboration of secondary sexual characters in that gender.  相似文献   

10.
    
We developed a set of eight polymorphic microsatellite loci for pronghorn, Antilocapra americana. We screened 233 individuals from the National Bison Range in Moiese, MT, and found allele numbers from three to 11 and heterozygosity levels ranging from 0.142 to 0.807. These results suggest that these loci will be useful in paternity analysis and basic population genetics applications.  相似文献   

11.
A hypervariable simple sequence locus and mitochondrial D-loop sequences were used to analyse genetically a natural population of the larger mouse-eared bat Myotis myotis in southern Bavaria. Tests for population subdivision and direct observations suggest that females return to their natal sites, while males disperse. The males present in female nursery colonies are not related to the females. Paternity assessment for 46 offspring from a particular nursery colony showed that there are no males that monopolize the reproduction, and that the resident males in the colony had only a small mating success. Instead, the results suggest that females actively seek matings outside their colony. Most interestingly, it appears that a group of males about 16 km away from the nursery colony had a relatively high mating success and that this group of males may be related to the females of the nursery colonies. If this finding can be confirmed in a larger study, it may have important consequences for future conservation strategies.  相似文献   

12.
    
Eleven polymorphic microsatellite loci were isolated in the passeriform Petronia petronia using the enrichment protocol FIASCO (fast isolation by AFLP of sequences containing repeats). We detected three to 13 alleles per locus in 25 specimens collected from an Italian population. The level of expected heterozygosity ranged from 0.439 to 0.856. One locus is sex linked to the Z chromosome. The total exclusionary probabilities using these loci for the first and the second parent were 0.978 and 0.999, respectively. These are the first microsatellite loci characterized from the rock sparrow that can be used for estimating population structure and for large‐scale parentage analysis.  相似文献   

13.
    
Group composition and mating system were investigated in wild Alaotran gentle lemurs (Hapalemur griseus alaotrensis) using genetic markers. These small-bodied herbivorous and cathemeral primates are endemic to the reed and papyrus beds around Lac Alaotra in Madagascar. They live in small groups in small, defended territories. Data were collected during the rainy seasons in 1996, 1997, and 1999, and include 99 individuals from 22 neighboring social groups and an additional 30 animals from other areas representing most of the geographic range. Animals were located by researchers canoeing in the marshes bordering the lake. After a group's size was determined by direct observation, all individuals were captured, marked, and released. During handling each individual was weighed and sexed, and hair samples for DNA extraction were collected. A 342 bp mtDNA control region sequence and 10 nuclear microsatellite loci provided multilocus genotypes that were used to assess pedigree relations and population structure. Alaotran gentle lemurs were found in groups of two to nine individuals (mean: 4.3), comprising one or two breeding females, their offspring, and one reproducing male. Solitary individuals of both sexes were encountered rarely. Breeding females were the permanent core of the social groups, whereas intergroup transfer of reproductive males was relatively frequent. Forty percent of all reproducing groups contained two breeding females, which were related to each other as closely as mother-daughter or full sisters. Parentage assessment revealed a variable mating system ranging from serial monogamy to polygyny within social groups. At least 8% of paternities involved extragroup males. Additional data on life history and reproduction are presented, and the social system of the Alaotran gentle lemur is discussed in the light of the new genetic findings.  相似文献   

14.
    
Large groups of related progeny, as can be collected from discrete egg masses or fruits, present excellent opportunities for parentage analysis by allowing the reconstruction of parental genotypes. Current techniques of parental genotypic reconstruction require the knowledge of at least one parental genotype. Here, I present a new computer program that reconstructs parental genotypes when no parents are known, provided that the progeny array contains only full and half siblings. The prospects for successfully reconstructing parental genotypes for such progeny arrays with unknown parents are nearly as good as those for the case when one parent is known with certainty.  相似文献   

15.
    
Sexual selection should produce sexual size dimorphism in species where larger members of one sex obtain disproportionately more matings. Recent theory suggests that the degree of sexual size dimorphism depends on physical and temporal constraints involving the operational sex ratio, the potential reproductive rate and the trade-off between current reproductive effort and residual reproductive value. As part of a large-scale experiment on dispersal, we investigated the mating system of common brushtail possums inhabiting old-growth Eucalyptus forest in Australia. Paternity was assigned to 20 of 28 pouch-young (maternity known) genotyped at six microsatellite loci. Male mating success was strongly related to body size and age; male body weight and age being highly correlated. Despite disproportionate mating success favouring larger males, sexual size dimorphism was only apparent among older animals. Trapping and telemetry indicated that the operational sex ratio was effectively 1 : 1 and the potential reproductive rate of males was at most four times that of females. Being larger appeared to entail significant survival costs because males 'died-off' at the age at which sexual size dimorphism became apparent (8-9 years). Male and female home ranges were the same size and males appeared to be as sedentary as females. Moreover, longevity appears to be only slightly less important to male reproductive success than it is to females. It is suggested that a sedentary lifestyle and longevity are the key elements constraining selection for greater sexual size dimorphism in this 'model' medium-sized Australian marsupial herbivore.  相似文献   

16.
    
Multiple paternity seems common within elasmobranchs. Focusing on two deep-sea shark species, the velvet belly lanternshark (Etmopterus spinax) and the slendertail lanternshark (Etmopterus molleri) we inferred the paternity in 31 E. spinax litters from Norway (three to 18 embryos per litter) and six E. molleri litters from Japan (three to six embryos), using 21 and 10 specific microsatellites, respectively. At least two E. spinax litters were sired from multiple fathers each, with highly variable paternal skew (1:1 to 9:1). Conversely, no clear signal of genetic polyandry was found in E. molleri.  相似文献   

17.
    
We isolated microsatellite loci for the Trinidadian guppy Poecilia reticulata from the Oropuche and Caroni drainages in Trinidad, using a modified enrichment protocol that provided 93% enriched libraries. The eight loci presented here are polymorphic, and have between seven and 18 alleles in 33–48 individuals initially screened. Observed heterozygosities in this sample range from 0.28 to 0.88. These loci significantly increase the number of polymorphic microsatellite markers available for paternity and population analysis in this species.  相似文献   

18.
Eighteen microsatellite loci were isolated from great tinamous (Tinamus major), which are large terrestrial birds found in the Neotropics. These are the first primers developed for the Order Tinamiformes. Paternity analyses are possible because the levels of heterozygosity are sufficiently high (0.29-0.90).  相似文献   

19.
Mating frequency of Vespa analis queens and the genetic relatedness of their workers was analyzed by DNA microsatellite genotyping. Of 20 colonies studied, 18 had a queen inseminated by a single male and two had queens each inseminated by two males. The estimated effective number of matings was 1.05 ± 0.037 (mean ± SE), with 75–85% of the offspring of the two multiply mated queens sired by a single male. The pedigree relatedness between nestmate workers averaged over the 20 colonies was estimated to be 0.74 ± 0.008, almost identical to the predicted value of 0.75 for colonies headed by a singly mated queen. Multiple matrilines; that is, the presence of workers not related to the current queens, were detected in six colonies, suggesting that queen replacement occurred via usurpation of the founding queens in these six colonies. These results demonstrate that the kin structure of V. analis is similar to that reported in other vespid species.  相似文献   

20.
Cloning of highly polymorphic microsatellites in the horse   总被引:22,自引:0,他引:22  
We have isolated equine microsatellites by screening a genomic library with (TG)n and (TC)n probes. TG microsatellites were found to be more abundant than TC repeats, with an estimated frequency of one per 100,000bp. Sequence analysis of eight TG-positive clones revealed varying structures of the repeat regions; perfect stretches of TG repeats, imperfect stretches of TG repeats and compound regions of TG and TC repeats. Five loci were analysed by PCR and showed extensive polymorphism; three to seven alleles and heterozygosities of 0.40-0.76 were observed when screening 20-30 unrelated individuals. The high degree of polymorphism, their abundance and the possibility of automating the typing procedure make these loci ideal for standardized paternity testing in the horse. Furthermore, we demonstrate that single hairs can be used as starting material for the PCR analysis.  相似文献   

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