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1.
The diet of fork-tailed (Oceanodroma furcata) and Leach's storm-petrel(O.leucorhoa) was studied at Petrel Island, a small island northof Hippa Island in the Queen Charlotte Islands, British Columbiain 1983. The diet of the two storm-petrel species consistedmostly of the amphipod Paracallisoma coecus and fish. Most fisheswhich could be identified were myctophids, and may have beenacquired by storm-petrels at night. Fishes increased while P.coecusdeclined in importance as a food over the nestling season ofthe storm-petrels. The amount of oil also declined in the Leach'sstorm-petrel diet over the season. Since P.coecus contains muchoil, the seasonal decline of both P.coecus and oil was probablyassociated. Other less important foods were jellyfishes, copepods,isopods, euphausiids, shrimp, squid and octopus. Jellyfishes(Velella velella) only occurred in the diet of Leach's storm-petrels,which may relate to that storm-petrel feeding in open oceanwhere V. velella occurs most frequently. The most numerous copepodwas Neocalanus cristatus, which was only observed in the storm-petreldiet early on during the study period. An abyssal copepod, Bathycalanusbradyi, and the isopod Cirolana californiensis (tentativelyidentified, the latter only previously known from sea canyonsoff California) were surprising food items of storm-petrels.Most euphausiid prey consisted of Thysanoessa spinifera andEuphausia pacifica.  相似文献   

2.
Fourteen polymorphic microsatellite loci were developed from an enriched genomic library of the widely distributed migratory North American dragonfly species, the common green darner (Anax junius). For a group of 22 larvae, these loci averaged 16 alleles, with individual loci ranging from nine to 29 alleles. Observed heterozygosity averaged 0.784 per locus.  相似文献   

3.
We developed primers for eight polymorphic microsatellite loci isolated from the collared pika, Ochotona collaris, and also tested nine loci previously developed for the American pika, O. princeps, for use in O. collaris. Forty-six individuals from an O. collaris population in the southern Yukon were genotyped using all 17 loci. The average number of alleles per locus was six and the average observed heterozygosity was 0.59. All loci were tested for use in four Asian pika species and all but two loci amplified reliably in these species.  相似文献   

4.
Primers for 10 polymorphic microsatellite loci were developed and characterized for the endangered oyster mussel Epioblasma capsaeformis from the Clinch River, Tennessee. Microsatellite loci also were tested in four other populations or species. Amplification was successful for most loci in these closely related endangered species or populations; therefore, a high level of flanking sequence similarity was inferred for this group of species and populations. Allelic diversity ranged from nine to 20 alleles/locus, and averaged 13.6/locus. This study demonstrated the feasibility of using polymerase chain reaction (PCR) primers to amplify microsatellite loci across freshwater mussel species to conduct population genetics studies.  相似文献   

5.
R. S. Bailey    R. Pocklington  P. R. Wrllrs 《Ibis》1968,110(1):27-34
In the course of the International Indian Ocean Expedition two storm-petrels, thought to be Oceanodroma matsudairae and O. monorhis, were encountered in the western Indian Ocean in some numbers. Two specimens of each species were collected, monorhis in the Arabian Sea, matsudairae off N.W. Australia. O. matsudairae, which had not been recorded before from these waters, appeafed to be concentrated within 5° of the equator and the birds probably belonged to the spring-breeding population of Volcano Island. O. monorhis was found mostly in the Arabian Sea. Bulweria bulwerii, for which there was but one certain Indian Ocean record, was also encountered several times.  相似文献   

6.
In 2003, birds similar to the extinct New Zealand storm-petrel Oceanites maorianus were observed in Hauraki Gulf NZ, raising the possibility of rediscovery after 150 years. O. maorianus has and continues to be surrounded by taxonomic uncertainty, being variously described as a distinct genus, a distinct species, or merely a plumage variant. This uncertainty has hindered conservation planning and funding for the species. Here we examine the taxonomic identity of the rediscovered birds and museum specimens using phylogenetic analysis of mitochondrial (1143 bp cytochrome b) and nuclear (890 bp β-fibrinogen) genes. Using cytochrome b sequence amplified from the 150+ year old specimens, we found that the extant and museum O. maorianus were the same taxon (0.01 genetic distance), with both differing from all other storm-petrel taxa. Using both genes, we examined the phylogenetic affinities of O. maorianus to the Oceanitinae and Hydrobatinae storm-petrels finding that O. maorianus was more closely aligned to Fregetta (0.08-0.09) than Oceanites (0.11-0.12), thereby confirming its status as a distinct taxon, not a plumage variant of O. oceanicus. Our analysis verifies that the previously presumed extinct New Zealand storm-petrel has been rediscovered and can now be assigned a conservation priority commensurate with its critically endangered status.  相似文献   

7.
We describe the first microsatellites for rockfishes in the diverse genus Sebastes. Clones containing microsatellites were isolated from the genomic library of a quillback rockfish, Sebastes maliger. Twelve microsatellites are characterized; six of these are polymorphic in quillback rockfish, and eight are polymorphic in at least one rockfish species on which they were tested. The number of alleles per variable locus ranged from 4 to 15 and averaged 6.8. The expected heterozygosities ranged from 0.38 to 0.79 and averaged 0.60 in these loci. These loci should prove valuable in studies examining species identification, population genetics, hybridization, paternity, kinship, and microsatellite evolution. Received September 8, 1998; accepted November 23, 1998.  相似文献   

8.
Here we describe 32 di‐, tri‐ and tetranucleotide microsatellite loci isolated by PIMA, a polymerase chain reaction (PCR)‐based procedure, for the common snook (Centropomus undecimalis). Five loci were monomorphic, and the remaining loci averaged 6.7 alleles per locus in a sample of 45 common snook. For polymorphic loci, expected heterozygosities ranged from 0.02 to 0.91 (mean = 0.538). Significant departures from Hardy–Weinberg equilibrium expectations occurred in two loci. Exact tests for genotype disequilibrium gave evidence for linkage at one pair of loci. Many cross‐species primer assays yielded PCR fragments of the expected size for 11 species of Centropomus and two species of the confamilial genus Lates.  相似文献   

9.
We have documented the first microsatellites isolated from a unionid and demonstrated that these markers can be useful for surveys of neutral genetic variation in several Lampsilis species. We describe the isolation and characterization of 15 polymorphic microsatellite DNA loci for the endangered unionid Lampsilis abrupta. Among individuals from five collections, allelic diversity ranged from six to 17 alleles and averaged 10.4 alleles per locus. Individual heterozygosity was observed to range from 20.0% to 86.7% and averaged 46.9%. Cross‐species amplification was investigated in nine additional Lampsilis species. A high level of flanking sequence similarity was inferred as 13 of 15 loci amplified in at least seven species.  相似文献   

10.
Three tilapiine species belonging to the endemic Lake Malawi species flock known as' chambo' Oreochromis ( Nyasalapia ) karongae , O. (N.) lidole and O. (N.) squamipinnis and the species Oreochromis (Oreochromis) shiranus were collected from the wild. These four species were analysed at 43 enzyme loci using starch gel electrophoresis. No significant deviations from Hardy-Weinberg equilibrium were observed after correcting for multiple simultaneous testing. The expected heterozygosity ( H e) was lowest in O. (O.) shiranus ( H e=0.082). The three chambo species had higher levels: H e=0.103 to H e=0.116. The three chambo species as a whole were polymorphic (99%) at 16 different loci sharing 10 of these in common. No fixed differences between the three chambo species were observed but highly significant allele frequency differences existed between all the chambo species. The F ST calculated for the three chambo species was 0051, closer to intra-specific than to inter-specific levels. O. (O.) shiranus could be clearly separated from all chambo species at five fixed loci. Comparison of the allozyme data from these species with five species from the same sub genera support the hypothesis that the chambo form a monophyletic group and that O. (N.) macrochir or a related species represents the sister taxon.  相似文献   

11.
The genetic structure of nine Peromyscus maniculatus nebrascensis demes from southeastern Wyoming was determined by analyzing allozymes encoded by 23 genetic loci with polyacrylamide gel electrophoresis. Genetic variability is extremely high for two genetic parameters; the proportion of loci heterozygous per individual averaged 0.16, and the proportion of loci polymorphic per deme averaged 0.41. Previous estimates of genetic heterozygosity for species within the genus Peromyscus have a mean of 0.06. The results of the present study suggest that genetic heterozygosity is considerably higher within P. maniculatus demes than within demes of other species in the genus. Geographic range is correlated with heterozygosity among Peromyscus species, as is adaptive divergence into broad-niched species. These correlates suggest that high heterozygosity may reflect an adaptation to a variable environment.  相似文献   

12.
Angelica sinensis (Apiaceae) is an endangered alpine herb that is widely used as a medicinal plant in traditional Chinese medicine (TCM). Wild populations of A. sinensis have become quite rare in China. Thus, population genetics studies of this species are urgently needed for its effective conservation and sustainable use. However, to date, no microsatellite loci have been isolated in A. sinensis. To address this issue, we isolated 18 polymorphic loci and genotyped 120 individuals collected from 6 populations. The number of alleles per locus ranged from 1.2 to 5.5, and the average was 2.4. The observed and expected heterozygosity per locus for a population varied, respectively, from 0.000 to 0.983 (averaged at 0.198) and from 0.066 to 0.661 (averaged at 0.333). Deviation from the Hardy–Weinberg equilibrium (p < 0.01) was observed for 4 to 14 loci in various populations. These microsatellite markers were cross-amplified in 10 species affinis, and 7 loci were successfully amplified in all species. These microsatellite markers are useful for genetic studies, the conservation management of A. sinensis, and identification of A. sinensis.  相似文献   

13.
Leontopithecus caissara is a critically endangered primate species from the Brazilian Atlantic Forest. Nineteen microsatellite loci, previously developed for congeneric species, were tested with 34 L. caissara individuals from Superagüi Island. Of the 19 loci, 17 (89.4%) produced robust alleles, nine (47.4%) of these proved to be polymorphic, with a total of 23 alleles and an average of 2.56 alleles per locus. Expected and observed heterozygosity averaged 0.483 and 0.561, respectively. The exclusion power for identifying the first parent of an arbitrary offspring was 0.315 over all loci. The results thus indicate both the usefulness and limitations of these nine microsatellite loci in the genetic analysis of L. caissara, as well as their potentiality for genetic investigation in other congeneric species.  相似文献   

14.
At St Kilda, Outer Hebrides, a large colony of great skuas Stercorarius skua feed extensively on one of the largest colonies of Leach’s storm-petrels Oceanodroma leucorhoa in Europe, but little is known about the dynamics of this predator–prey system. Recently published population estimates of storm-petrels make it possible to estimate the impact of skua predation for the first time. Although skuas in the southern hemisphere catch petrels attending breeding colonies at night, it is not known whether congeners in the northern hemisphere also forage during the hours of darkness. We found (using radio-transmitters) that skuas regularly forage at night and (using light intensifying equipment) observed them catching storm-petrels at night. However, skuas also foraged during daylight hours, and it is unknown whether they might also catch storm-petrels at sea. Data on diet composition reveals that the proportion of storm-petrels in skua diet declined between 1996 and 1997, but remained constant thereafter. Although a large proportion of the storm-petrel prey is likely to consist of non-breeders, numbers consumed suggest that breeders and an unknown quantity of transients may also been eaten. The numbers of storm-petrels eaten are not sustainable and may result in substantial long-term population declines. Under current conditions, maintenance of large populations of both Leach’s storm-petrels and great skuas at St Kilda appears to be mutually exclusive.  相似文献   

15.
We tested 47 tetranucleotide microsatellite loci developed for the domestic dog in four species of Neotropical canids, aiming to produce a standardized set that could be successfully used even in noninvasive samples across this group. We identified 13 suitable loci, nine of which constitute a standardized set for all species. Considering only the ideal panel of nine loci, the mean expected heterozygosity (averaged across species) per locus ranged from 0.58 to 0.92 (overall mean 0.76), and the maximum probability of identity value was 1.3 × 10?9. This set of loci has a great potential for application in evolutionary, ecological and conservation studies.  相似文献   

16.
Primers for six polymorphic microsatellite loci were developed for the endangered northern riffleshell Epioblasma torulosa rangiana from the Sydenham River, Ontario, Canada. These loci along with an additional nine microsatellite loci, developed from other unionoid species, available in the literature, were tested and characterized on individuals from two populations in the Allegheny River; one population in French Creek, PA, USA, and one population from the Sydenham River. Allelic diversity ranged from two to 28 alleles per locus and averaged 13.7 per locus. These primers are being used in a rangewide study on the conservation genetics of remaining extant populations of the northern riffleshell.  相似文献   

17.
Oncomelania lindoensis from Lake Lindu, Sulawesi, was characterizedfor genetic variation at 21 allozyme loci and compared withO. hupensis (China) and O. quadrasi (Philippines). Geneticdistances and interpopulation patterns of allele-sharing pointto a closer relationship between Sulawesi and the Philippines(Nei's unbiased genetic distances (D) averaged 0.50) than betweenSulawesi and China (D= 0.79). These data, coupled with a considerationof the geographic distribution of the genus, support the hypothesisthat the Sulawesi Oncomelaniaoriginated by avian-facilitated colonizationfrom the Philippines about two million years ago. Oncomelania from Sulawesi were originally described as subspecificallydistinct: Oncomelania hupensis lindoensis. However, the allopatricdistribution, unique alleles at five loci, and significant geneticdistances from congeners in Mindanao and elsewhere in the Philippinessuggest that this taxon should be distinguished as a full specieswithin the Oncomelania hupensis species group, namely: O. lindoensisDavis & Carney 1973. Comparison with published data on variationwithin quadrasi and in three Chinese subspecies of hupensisshowed that D values increase with taxonomic level in this speciesgroup. D averaged 0.15 (0–0.26) within Chinese subspeciesand 0.04 (0–0.13) within the Philippines, but was 0.30(0.20–0.45) between Chinese subspecies, and 0.48–0.80between the three species (hupensis, quadrasi and lindoensis).The genotypic cluster species concept and these multilocus geneticdistances can be used to help define species and subspeciesin these medically important snails. (Received 14 May 1997; accepted 20 April 1998)  相似文献   

18.
We developed 13 species‐specific microsatellite markers for the federally endangered Atlantic slope unionid Alasmidonta heterodon. Four to 18 alleles per locus were observed among 30 individuals. Observed heterozygosity throughout the loci ranged from 26.9 to 86.2% and averaged 63.6%. Estimates of individual pairwise genetic distances indicated that levels of genetic diversity among loci were sufficient to produce unique multilocus genotypes for all animals surveyed. Randomization tests showed that genotypes for this collection were consistent with Hardy–Weinberg expectations, and no significant linkage disequilibrium was observed between loci. These loci therefore appear suitable for population surveys, kinship assessment and other such applications.  相似文献   

19.
Populations of mudshrimp, Austinogebia edulis, in the intertidal mud flat of western Taiwan have severely declined due to habitat destruction and overfishing in the past decades. Nine polymorphic microsatellite loci were isolated for this ecologically threatened species by using a polymerase chain reaction-based procedure. The number of alleles per locus ranged from five to 14 in 20 specimens from Central West Taiwan. Observed and expected heterozygosities ranged from 0 to 0.2500 (averaged at 0.0944) and 0.7333 to 0.9385 (averaged at 0.8524), respectively. There were significant departures from Hardy–Weinberg expectations. Significant LD was discovered in most loci. These primers may provide a tool for understanding population structure in A. edulis. Tzen-Yuh Chiang and Hung-Du Lin contributed to the study equally.  相似文献   

20.
Our understanding of Glossina fuscipes fuscipes, a major vector of sleeping sickness, has been severely constrained by a lack of genetic markers for mapping and population genetic studies. Here we present 10 newly developed microsatellite loci for this tsetse species. Heterozygosity levels in Moyo, an Ugandan population, averaged 0.57, with only two loci showing very low heterozygosity. Five loci carried more than six alleles. Together with five recently published microsatellite loci, this brings the number of available microsatellite loci for this species to 15. Their availability will greatly facilitate future studies on the genetics of this important human disease vector.  相似文献   

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