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1.
We examined vervet monkey (Chlorocebus pygerythrus) space use using GPS/UHF telemetry data from 10 vervet monkeys across six troops over 9 months within a 420 ha suburban eco‐estate. We documented a mean home range of 0.99 km2 (95% MCP) and 1.07 km2 (95% KDE) for females (n = 6), 1 km2 (95% MCP) and 1.50 km2 (95% KDE) for males (n = 4) and 0.87 km2 (95% MCP) and 1.12 km2 (95% KDE) for troops (n = 6), respectively, indicating that males and larger troops had larger home ranges. These relatively small home ranges included shared territorial boundaries and high home range overlap. Vervet monkey movements indicated higher morning activity levels, and habitat selection indicated significantly more use of golf course, urban residential and forest, thicket and woodland areas, and avoidance of wetland, grassland and shrub, and urban built‐up areas. Our results suggest that modified habitat use by vervet monkeys is a consequence of behavioural facilitation to access highly available food resources, thereby facilitating their persistence in green spaces in urban areas of South Africa. Conflict management is dependent on the conservation of sufficient natural habitats and food resources, to minimise their dependence on anthropogenic supplementary food resources and consequently reduce human–monkey conflict.  相似文献   

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This study investigated fluctuations in hematological values of 50 wild-caught vervet monkeys (African green monkeys, grivets, Chlorocebus aethiops) during habituation to captivity. The monkeys were categorized into four groups according to age and sex viz adult males, adult females, juvenile males, and juvenile females. The erythrocyte values were significantly higher (P<0.05) in the adult males than in the other animals. There was an increase in most of the erythrocyte parameters studied during the monitoring period with the most significant being hemoglobin, hematocrit, and mean corpuscular volume. However, the red cell distribution widths, which were higher in adult females, declined. The total white blood cell (WBC) counts, which were higher in adult females than in the other animals, were closely correlated with granulocytes counts. The WBC levels decreased in all the animals throughout the 8 months study, indicating gradually decreasing stress, but they were relatively stable in males. The platelet counts declined significantly (P<0.05) and at 8 months post capture the counts were higher in females than in males. The juvenile female platelet counts were relatively stable during the monitoring period. The maintenance of the monkeys on an improved stable diet and in environment-controlled housing combined with progressing psycho-physiological adaptation may be important factors for the gradual improvements of the hematological values recorded. There were wide variations in these between individual animals emphasizing the need for long adaptation combined with establishment of individual baseline values before experimental studies.  相似文献   

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5.
Unrelated male primates frequently cohabit in bisexual groups and, despite being reproductive competitors, have been shown to cooperate in ways that are associated with reproductive success. Such coalitions between males are common in some taxa, where they can serve two primary functions – status management and improved mating opportunities – that subserve long‐ and short‐term objectives. Here, we use observational data to provide information on male coalitions in vervet monkeys (Chlorocebus pygerythrus), a guenon with a multimale group structure. We recorded a total of 62 coalitions from two troops across a 10‐mo period at Samara Game Reserve, South Africa. We found that males who were more frequently associated spatially and who had groomed one another were more likely to form coalitions and did so against higher‐ranking opponents. This was not linked to any evidence that coalitionary aggression provided either short‐ or long‐term reproductive benefits for the aggressors and coalitions were not restricted to the mating season. There was little evidence that particular individuals were targeted, reciprocation between partners was not observed, and recent immigrant males were not targeted disproportionately. Our data suggest that within‐group coalition formation between vervet males may represent something close to an ancestral state whereby males form ad hoc coalitions opportunistically, joining an ongoing dyadic contest to target an opponent without facing the possible risks of dyadic contest, such as a greater chance of injury.  相似文献   

6.
I study the relation between orphanhood and fertility patterns in young adults using a longitudinal survey from the city of Cape Town, South Africa. The data set combines two survey waves with a year-by-year life history calendar that records key outcomes (e.g., schooling, work, fertility). It also provides information on so-called ‘parental investments’ (time and material support), family background, and literacy and numeracy test scores. I find that orphans exhibit significantly higher rates of teenage pregnancy. In particular, teenage motherhood is 19% points more likely among (female) orphans. These results suggest that orphanhood may leave a long-lasting ‘imprint’ in terms of premature fertility, especially in teenage females.  相似文献   

7.
From 1975 through 1991, three sets of twins were born from a total of 693 live and stillborn births (0.43%) at the UCLA/Sepulveda Veterans Administration Medical Center Nonhuman Primate Research Laboratory, CA. None of the twin's mothers were related. Positive patrilineal relationships have not been established; however, a brother (not a twin) of the first set of twins may have fathered the third set. All twins were born to multiparous females and, in each case, only one infant survived beyond 4 days. One set of twins was dizygotic; the genetic status of the others is unknown. © 1994 Wiley-Liss, Inc.  相似文献   

8.
Ascidians are sessile marine chordate invertebrates found along seashores worldwide and are typically regarded as invasive organisms. Knowledge concerning their global genetic structure and subsequent invasive potential is limited. Here, we identified three ascidians—Ciona robusta, Ciona savignyi, and Styela clava from the northeast region of China using morphological characteristics and mitochondrial cytochrome c oxidase subunit I (cox1) as genetic marker. We additionally used phylogenetics to aid in the identification of these three species. The results of a population genetic analysis showed that among the three species, the level of haplotype diversity was particularly high within C. savignyi, and nucleotide diversity varied moderately. We divided the three species separately into native and invasive populations using 170 cox1 sequences from global resources to explore population genetic structure and invasive potential. Although in the network analysis Ciona spp. formed haplogroups of native and invasive populations, some haplotypes were still shared. We found that the haplotypes did not cluster within the network of S. clava. Our AMOVA results also showed that Ciona spp. had a weak genetic structure, and less genetic differentiation was present in S. clava. These data suggest that there are extensive incursions of these three ascidians into different geographical regions. Global comparisons of ascidian populations will help in the understanding of their population genetic structure and invasive potential, hence providing important insights regarding conservation as well as management.  相似文献   

9.
Two mitochondrial DNA segments of the bigeye tuna (Thunnus obesus) were amplified by polymerase chain reaction (PCR), and restriction fragment length polymorphism (RFLP) analyses of these segments were used for the genetic stock study. The variation in a segment flanking the ATPase and COIII genes was low; only two genotypes (α and β) were detected by RsaI digestion. Yet a large difference in the genotype distribution was observed between ocean basin samples. The α type predominated in four Atlantic samples, where 178 of 244 individuals were the α type. In contrast, only one of 195 individuals collected in the Indo‐Pacific was the α type? The frequency of the α type varied considerably from 0 to 80% among seven samples collected off the Cape of Good Hope. The variation found in the other segment, containing the D‐loop region, was much higher; two endonucleases (DpnII and RsaI) detected five genotypes each and 15 composite genotypes. A highly significant difference in genotype frequencies was observed between the Atlantic and Indo‐Pacific samples, but no heterogeneity was observed among the four Atlantic or among four Indo‐Pacific samples. These results clearly indicate that not only gene flow, but also fish migration, between the Atlantic and Indian Oceans are severely restricted, and that fishes from these distinct stocks are intermingling around South Africa. The simple and diagnostic genetic marker found in this study can be used to estimate mixing ratios between Atlantic and Indian stocks around South Africa.  相似文献   

10.
Insertions and deletions (indels) result in sequences of various lengths when homologous gene regions are compared among individuals or species. Although indels are typically phylogenetically informative, occurrence and incorporation of these characters as gaps in intraspecific population genetic data sets are rarely discussed. Moreover, the impact of gaps on estimates of fixation indices, such as F(ST), has not been reviewed. Here, I summarize the occurrence and population genetic signal of indels among 60 published studies that involved alignments of multiple sequences from the mitochondrial DNA (mtDNA) control region of vertebrate taxa. Among 30 studies observing indels, an average of 12% of both variable and parsimony-informative sites were composed of these sites. There was no consistent trend between levels of population differentiation and the number of gap characters in a data block. Across all studies, the average influence on estimates of PhiST was small, explaining only an additional 1.8% of among population variance (range 0.0-8.0%). Studies most likely to observe an increase in PhiST with the inclusion of gap characters were those with < 20 variable sites, but a near equal number of studies with few variable sites did not show an increase. In contrast to studies at interspecific levels, the influence of indels for intraspecific population genetic analyses of control region DNA appears small, dependent upon total number of variable sites in the data block, and related to species-specific characteristics and the spatial distribution of mtDNA lineages that contain indels.  相似文献   

11.
Blood and saliva samples were collected from 330 vervet monkeys living in 30 troops in central and southern Kenya. The saliva samples were tested for the presence of human-type ABH antigens by standard agglutinationinhibition tests. This population of vervets is the first in which the O phenotype has been found to occur. The gene frequencies in the overall population are as follows: A, 0.74; B, 0.21; and O, 0.05. The serum samples were tested for the presence of agglutinins having specificities like those of human anti-A and anti-B. Ten percent of the vervets have anomalous combinations of salivary antigens and serum agglutinins. The nature of the anomalies is described and a hypothesis presented to account for these observations.  相似文献   

12.
We describe a scenario of plant speciation across a relict forest archipelago in South Africa involving Pleistocene habitat expansion-contraction cycles, dispersal and adaptation to lower temperatures. This is the first population level study using molecular data in South African forests and has significant implications for conservation efforts in this area. Populations of the mesophytic forest floor herbs Streptocarpus primulifolius sensu lato and Streptocarpus rexii were sampled throughout their range in the naturally fragmented forests of eastern South Africa in order to investigate population genetic and phylogenetic patterns within the species complex, using nuclear microsatellites, nuclear ribosomal ITS (internal transcribed spacer) sequences and chloroplast genome sequences. S. primulifolius harbours high levels of genetic diversity at both the nuclear (mean HE = 0.50) and the chloroplast level (each population fixed for a unique haplotype). This is consistent with populations of these coastal species being Pleistocene relicts. In contrast, populations of S. rexii in cooler habitats at higher altitudes and lower latitudes harbour little or no nuclear genetic diversity (mean HE = 0.09) and most share a common chloroplast haplotype. The split of S. rexii from populations intermediate between the two species (S. cf. primulifolius) occurred between 0 and 0.44 million years ago according to the calibrated ITS phylogeny of the taxa. The low genetic diversity and homogeneity of S. rexii is congruent with this species having reached its current range during the Holocene. We found no evidence of monophyly of any of the taxa in this study, which we consider a consequence of recent evolution in a fragmented habitat.  相似文献   

13.
Four new species of oribatid mites of the genus Crotonia , ( C. pauropelor sp. nov., C. dicella sp. nov., C. lyrata sp. nov. and C. ecphylla sp. nov. ) are described from soil and plant litter from South Africa. Crotonia pauropelor, C. dicella and C. ecphylla are allied to the 'capistrata' species-group, previously known only from Queensland, Australia, in that they possess the full complement of c setae on the notogaster. They differ in having eight pairs rather than nine pairs of genital setae. In addition, C. ecpylla is unusual in the genus Crotonia in that it appears to possess two pairs of setae on each of the second epimera. Crotonia lyrata has only two pairs of c setae and is allied to the 'cophinaria' species-group. This is only the second published record of the genus Crotonia from South Africa, and the first of any named species. A key to the African Crotonia species is provided, which includes the only two previously known species C. alluaudi and C. rothschildi (Berlese, 1916).  相似文献   

14.
Resolving the identity, phylogeny and distribution of cryptic species within species complexes is an essential precursor to management. The bonnethead shark, Sphyrna tiburo, is a small coastal shark distributed in the Western Atlantic from North Carolina (U.S.A.) to southern Brazil. Genetic analyses based on mitochondrial markers revealed that bonnethead sharks comprise a species complex with at least two lineages in the Northwestern Atlantic and the Caribbean (S. tiburo and Sphyrna aff. tiburo, respectively). The phylogeographic and phylogenetic analysis of two mitochondrial markers [control region (mtCR) and cytochrome oxidase I (COI)] showed that bonnethead sharks from southeastern Brazil correspond to S. aff. tiburo, extending the distribution of this cryptic species >5000 km. Bonnethead shark populations are only managed in the U.S.A. and in the 2000s were considered to be regionally extinct or collapsed in southeast Brazil. The results indicate that there is significant genetic differentiation between S. aff. tiburo from Brazil and other populations from the Caribbean (ΦST = 0.9053, P < 0.000), which means that collapsed populations in the former are unlikely to be replenished from Caribbean immigration. The species identity of bonnethead sharks in the Southwest Atlantic and their relationship to North Atlantic and Caribbean populations still remains unresolved. Taxonomic revision and further sampling are required to reevaluate the status of the bonnethead shark complex through its distribution range.  相似文献   

15.
We analyzed mtDNA polymorphisms (parts of control region, ND5, ND2, Cytb, 12S, together 902 bp) in 59 scat and 18 tissue samples from 13 Indian populations of the critically endangered Indian tiger (Panthera tigris tigris), along with zoo animals as reference. Northern tiger populations exhibit two unique haplotypes suggesting genetic isolation. Western populations from Sariska (extinct in 2004) and Ranthambore are genetically similar, such that Ranthambore could serve as a source for reintroduction in Sariska. Zoo populations maintain mitochondrial lineages that are rare or absent in the wild.  相似文献   

16.
Hybridization between the North American menhadens Brevoortia smithi , Brevoortia tyrannus and Brevoortia patronus has been reported by numerous authors, based primarily on the morphological intermediacy of hybrids relative to each parental type. In this study, genetic characterization of individuals in areas previously designated as hybrid zones validates the presence of F1 hybrids. Evidence from microsatellite genotypes indicates that B. patronus and B. smithi are parental species of hybrids on both sides of the Florida peninsula, and mitochondrial DNA (mtDNA) haplotypes suggest a maternal contribution by B. smithi in each case. Hybrids between B. tyrannus and B. smithi were not identified in this study. The presence of B. patronus on the Atlantic coast of Florida, coupled with admixture between this species and B. tyrannus , has likely influenced the mixed lineage assortment of mtDNA haplotypes demonstrated in this study and in previous studies.  相似文献   

17.
The cheetah (Acinonyx jubatus) has been described as a species with low levels of genetic variation. This has been suggested to be the consequence of a demographic bottleneck 10 000–12 000 years ago (ya) and also led to the assumption that only small genetic differences exist between the described subspecies. However, analysing mitochondrial DNA and microsatellites in cheetah samples from most of the historic range of the species we found relatively deep phylogeographic breaks between some of the investigated populations, and most of the methods assessed divergence time estimates predating the postulated bottleneck. Mitochondrial DNA monophyly and overall levels of genetic differentiation support the distinctiveness of Northern‐East African cheetahs (Acinonyx jubatus soemmeringii). Moreover, combining archaeozoological and contemporary samples, we show that Asiatic cheetahs (Acinonyx jubatus venaticus) are unambiguously separated from African subspecies. Divergence time estimates from mitochondrial and nuclear data place the split between Asiatic and Southern African cheetahs (Acinonyx jubatus jubatus) at 32 000–67 000 ya using an average mammalian microsatellite mutation rate and at 4700–44 000 ya employing human microsatellite mutation rates. Cheetahs are vulnerable to extinction globally and critically endangered in their Asiatic range, where the last 70–110 individuals survive only in Iran. We demonstrate that these extant Iranian cheetahs are an autochthonous monophyletic population and the last representatives of the Asiatic subspecies A. j. venaticus. We advocate that conservation strategies should consider the uncovered independent evolutionary histories of Asiatic and African cheetahs, as well as among some African subspecies. This would facilitate the dual conservation priorities of maintaining locally adapted ecotypes and genetic diversity.  相似文献   

18.
This study was designed to evaluate the timecourse of ovarian and pituitary endocrine events throughout the menstrual cycle in the vervet monkey, and whether circulating luteinizing hormone (LH) or the uterus regulates the functional lifespan of the vervet corpus luteum. Daily saphenous blood samples were collected from adult females (1) during spontaneous menstrual cycles (n = 7), and (2) during cycles in which a gonadotropin-releasing hormone antagonist (acyline) was administered for 3 days at midluteal phase (n = 3), and (3) for 30 days following recovery from hysterectomy (n = 4). Estradiol (E) and progesterone (P) levels were assayed using electrochemoluminescent assays. Gonadotropin levels were measured by radioimmunoassay using reagents developed for the assay of follicle-stimulating hormone and LH in macaques. Spontaneous cycles exhibited a midcycle E rise (476+/-49 pg/ml), engendering an LH surge, 12+/-1 days after onset of menses, followed by a luteal phase with peak P levels of 4.7+/-0.9 ng/ml. Histologic evaluation of the ovaries at late follicular phase or early luteal phase revealed the presence of a single, large Graafian follicle or developing corpus luteum, respectively. Acyline treatment caused a significant (P<0.05) decline in P levels (2.9+/-0.5 vs 0.5+/-0.3 ng/ml, 0 vs 48 h post-treatment) and premature menstruation compared with untreated controls (P<0.05). Hysterectomy had no apparent effect on the monthly pattern or levels of circulating E or P. Thus, the characteristics and regulation of the ovarian cycle in vervets appear similar to those in women and macaques, with cyclicity dependent on pituitary gonadotropin hormones and independent of a uterine luteolytic factor.  相似文献   

19.
The wreckfish Polyprion americanus , a large [>1 m total length ( L T)] demersal teleost, is distributed globally in temperate waters, including both sides of the North and South Atlantic Oceans, the Mediterranean, the western South Pacific, and the southern Indian Ocean. Wreckfish spawn off the south-eastern U.S. on an area of the Blake Plateau (the Charleston Bump) characterized by an extensive ridge having approximately 100 m relief, in 450–600 m depths. Juvenile wreckfish (<60 cm L T) are pelagic and, in the North Atlantic, are not reported from the Blake Plateau fishing area, but occur in by-catch and fishery landings in the eastern Atlantic. Analysis of nine restriction fragment length profiles from a PCR-amplified fragment (∼1.5 kb) of the ND1 mitochondrial gene indicated no stock separation between eastern North Atlantic (Azores, Majorca, Madeira), and western North Atlantic (Blake Plateau) wreckfish. Restriction site differences separate western South Atlantic wreckfish from the North Atlantic; however, South Atlantic wreckfish share restriction-site similarities with western Pacific wreckfish that are not shared with North Atlantic wreckfish. North Atlantic circulation provides a mechanism for a long-lived pelagic stage to be dispersed from Blake Plateau spawning grounds to the eastern North Atlantic. Global circulation patterns may explain both the dispersal of mtDNA haplotypes and the disjunct distribution of wreckfish body lengths in a temperate, deep-water vagile species with an extended pelagic juvenile stage such as wreckfish.  相似文献   

20.
The population genetic structure of the Anopheles gambiae in western Kenya was studied using length variation at five microsatellite loci and sequence variation in a 648-nt mtDNA fragment. Mosquitoes were collected from houses in villages spanning up to 50 km distance, The following questions were answered, (i) Are mosquitoes in a house more related genetically to each other than mosquitoes between houses? (ii) What degree of genetic differentiation occurs on these geographical scales? (iii) How consistent are the results obtained with both types of genetic markers? At the house level, no differentiation was detected by FST and RST, and the band sharing index test revealed no significant associations of alleles across loci. Likewise, indices of kinship based on mtDNA haplotypes in houses were even lower than in the pooled sample. Therefore, the hypothesis that mosquitoes in a house are more related genetically was rejected. At increasing geographical scales, microsatellite allele distributions were similar among all population samples and no subdivision of the gene pool was detected by FST or RST. Likewise, estimates of haplotype divergence of mtDNA between populations were not higher than the within population estimates, and mtDNA-based FST values were not significantly different from zero. That sequence variation in mtDNA provided matching results with microsatellite loci (while high genetic variation was observed in all loci), suggested that this pattern represents the whole genome. The minimum area associated with a deme of A. gambiae in western Kenya is therefore larger than 50 km in diameter.  相似文献   

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