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1.
This paper reports the results of the first study on secondary seed removal of seeds dispersed by Sykes’ monkeys (Cercopithecus albogularis) using camera traps in Africa. Patterns of primary seed dispersal are often superimposed by secondary conveyance, emphasising the need to study these secondary processes carefully. As the agents and mechanisms of seed dispersal are often concealed, being carried out by cryptic or nocturnal animals in dense vegetation, camera trapping was deemed a viable means to investigate secondary removal of seeds disseminated by C. albogularis in the Western Soutpansberg, South Africa. Camera traps were established at preferred feeding trees of the focal Sykes’ monkey group to identify animal species that remove seeds and fruits spat and dropped to the forest floor and seed removal observations were carried out. This method proved to be effective in identifying seed removers and also allowed to get indications about the quantities of seeds removed. Ten animal species were recorded visiting the trees, of which eight were observed removing seeds and fruits. Overall seed and fruit removal rates were high, indicating that the foraging behaviour of C. albogularis attracts many terrestrial frugivores. 相似文献
2.
The volatile constituents of nine liverworts species (Asterella marginata, Dumortiera hirsuta, Fossombronia swaziensis, Marchantia pappeana, Marchantia polymorpha subsp. ruderalis, Pallavicinia lyellii, Plagiochasma rupestre, Riccia albolimbata and Symphyogyna podophylla) from South Africa were determined by gas chromatography. Where possible the volatile constituents identified were compared to those reported for the same species from other countries. Among the analysed liverworts, the chemical compositions of A. marginata, F. swaziensis, M. pappeana, and R. albolimbata are reported for the first time. Each of the analysed liverwort species produced its own characteristic components. Thujopsanes, chamigranes and cuparanes were found to be the most characteristic components of M. polymorpha subsp. ruderalis. The presence of dumortane-type sesquiterpenoids in D. hirsuta indicated that this species is similar in chemistry to an Argentinean sample. This is one of only a handful of reports on the presence of this sesquiterpene-type in liverworts. Simple thallose liverworts, S. podophylla and P. lyellii, were characterized by the presence of labdane-type diterpenoids. In addition, the antimicrobial activities of chloroform:methanol (1:1) extracts of the liverworts were evaluated against several important human pathogens using the serial dilution assay. Four of the liverwort species were active against Pseudomonas aeruginosa with MIC values ranging from 0.50 to 1.0 mg/mL. Some activity (MIC value of 1.0 mg/mL) was also recorded for the crude extracts of P. lyellii and M. pappeana against Escherichia coli. The extract of S. podophylla displayed the best activity towards the yeast Cryptococcus neoformans (MIC = 1.0 mg/mL). Although approximately 300 liverwort species occur in southern Africa, a Scopus search confirmed that this is the first report of the volatile profiles and biological properties of species from the region. 相似文献
3.
Marna Visagie;Robert S. Davis;Jan A. Venter;Terry-Lee Honiball; 《Conservation Science and Practice》2024,6(9):e13214
Despite being resident or reintroduced to multiple South African protected areas, spotted hyaena (Crocuta crocuta) have been subject to limited population monitoring and are not managed in the same intensive way as other large carnivores. Considering the species' significant influence on ecosystem processes, robust estimates of population density are necessary to inform conservation management. In this study, we ran a single-season camera trap survey in the Main Camp section of Addo Elephant National Park (Addo), South Africa, and used spatial capture-recapture (SCR) models to estimate spotted hyaena population density. Spotted hyaena density was estimated to be 11.13 (± SE 1.96) individuals/100 km2, with an estimated abundance of 37 (± SE 6.44) individuals. Using our database of sexed spotted hyaena individuals, we found no significant difference for sex-specific SCR parameters (baseline encounter probability and spatial scale parameter), suggesting the incorporation of sex-specific information may not be as necessary for spotted hyaena as it is for territorial felids and other species with more pronounced differences in range size. Spotted hyaena density in Addo was comparable to previous SCR studies and towards the higher end of known densities. Our estimate provides an important baseline for monitoring reintroduction success in Addo, and we advocate for increased SCR monitoring of spotted hyaena in South African protected areas to inform a metapopulation approach to the species' management. 相似文献
4.
Abstract. A model is proposed for the fitting of species-area curves to data from the Stellenbosch region, South Africa. Basic assumptions of the model are finiteness of the number of species in a finite area, and random distribution of plant species over the region. The model involves a distribution of densities of different species, and the parameters of this distribution are useful for describing and classifying communities. The data of the Stellenbosch region suggest that the assumptions of the model break down in areas greater than 500 m2. 相似文献
5.
《Systematic and applied microbiology》2023,46(5):126452
A genealogical concordance approach was used to delineate strains isolated from Acacia dealbata and Acacia mearnsii root nodules in South Africa. These isolates form part of Bradyrhizobium based on 16S rRNA sequence similarity. Phylogenetic analysis of six housekeeping genes (atpD, dnaK, glnII, gyrB, recA and rpoB) confirmed that these isolates represent a novel species, while pairwise average nucleotide identity (ANIb) calculations with the closest type strains (B. cosmicum 58S1T, B. betae PL7HG1T, B. ganzhouense CCBAU 51670 T, B. cytisi CTAW11T and B. rifense CTAW71T) resulted in values well below 95–96%. We further performed phenotypic tests which revealed that there are high levels of intraspecies variation, while an additional analysis of the nodA and nifD loci indicated that the symbiotic loci of the strains are closely related to those of Bradyrhizobium isolates with an Australian origin. Strain 14ABT (=LMG 31415 T = SARCC-753 T) is designated as the type strain of the novel species for which we propose the name Bradyrhizobium xenonodulans sp. nov. 相似文献
6.
Janette Deacon 《Evolutionary anthropology》1999,8(2):48-64
The total number of rock art sites in South Africa certainly is in excess of 30,000. Collectively, they include well over a million images. However, fewer than 10,000 sites are listed on official databases. One reason for the lack of documentation is the high cost of establishing and maintaining recording programs. There is also a low level of public interest in rock art because both the art and the history of indigenous peoples have been neglected in school and university curricula. Matters are improving: At least one postgraduate university course dedicated to rock art will be offered at the University of the Witwatersrand beginning in 1999. Moreover, the gradual inclusion of cultural resources in heritage conservation and management programs is continuing. The significance of the oversight in the past is magnified if we consider the fragility of the art and the potential wealth of information it holds for understanding the evolution of South African society over the past 30,000 years. Rock art is an irreplaceable historical archive of extraordinary value. Although no one would dispute that this art must survive intact into the next millennium, research into its meaning is equally important if we are to convince the public that the art is worth saving. It is in this latter field that South African researchers have made a significant contribution to rock art studies in the past three decades. 相似文献
7.
South African coastal forests form part of two critically endangered eco‐regions and harbor an extinction debt. Remaining fragments are small, isolated, and embedded within a range of human land‐use types. In this study, we ask: how should we invest conservation resources if we want to restore this landscape and prevent predicted extinctions? To answer this question, we use path analyses to determine the direct and indirect effects of forest area, forest connectivity, and matrix land‐use types on species richness within five bird feeding guilds. We found that forest connectivity had a significant direct effect on insectivores—fragments that were more connected had more species of insectivores than those that were isolated. Moreover, forest area had a significant indirect effect on insectivores that was mediated through tree species richness. Larger fragments had more species of trees, which led to more species of insectivores. Fragment area, connectivity, matrix land‐use type, and tree species richness had no significant effects on the species richness of frugivores, nectarivores, granivores, or generalist feeders. To conserve insectivores in coastal forests, conservation efforts should focus on maximizing fragment connectivity across the landscape, but also protect the tree community within fragments from degradation. This can be achieved by including matrix habitats that adjoin forest fragments within forest conservation and restoration plans. Natural matrix habitats can increase connectivity, provide supplementary resources, buffer fragments from degradation, and could play an important role in safeguarding diversity and preventing extinctions in this threatened human‐modified landscape. 相似文献
8.
ROGER N. HUGHES 《Zoological Journal of the Linnean Society》1978,64(2):111-127
D. corallinacewn forms sheet-like colonies at Mean Low Water (MLW) on exposed rocky shores: S. natalensis forms loose aggregations under stones below MLW in more sheltered situations. Both species released young from July— December. D. corallinaceun has single embryos in capsules brooded free in the mantle cavity; S. natalensis has 20–40 embryos per capsule, the latter being attached to the roof of the shell and hanging through a dorsal slit in the mantle. The morphology of the crawling young is similar in both species, resembling adult errant prosobranchs. D. corallinaceum has a stouter, more streamlined protoconch than S. natalensis correlated with the more turbulent water of its habitat. The crawling young secrete a sticky mucous trail for adhesion to the substratum. They are strongly photopositive until settlement. D. corallinaceum can settle within 24 hours but may delay settlement to 4–5 days if suitable substrata are absent. Metamorphosis is complete 2 days after settlement. D. corallinaceum prefer to settle on Lithothamnion which is easily eroded by the radula to provide a groove for rapid, firm attachments to the substratum. Both species feed from mucous nets, S. natalensis having a slower feeding rhythm commensurate with its larger size. Contiguous pairs of S. natalensis have synchronised feeding rhythms, probably to reduce mutual net robbing. Particles are also filtered out of suspension; many particles are rejected in the pseudofaeces but some are ingested. D. corallinaceum and S. natalensis have many similar ecologically equivalent species throughout the warm temperate and tropical seas of the world. 相似文献
9.
10.
A. R. Wood 《Mycological Progress》2007,6(2):93-99
The holdings of rust fungi on Grewia species (Tiliaceae) housed in the South African National Collection of Fungi (PREM) were examined. They belong to three morphologically
similar, but clearly separable, species of Uredopeltis, and a species of Uredo. Each rust species has a distinct and restricted host range. Ravenelia atrides is a species of Uredopeltis and is transferred accordingly. Several specimens previously accessioned under R. atrides however belong to U. chevalieri. The specimens previously accessioned under Uredo grewiae belong to U. flava, and not U. chevalieri. Three specimens are best placed in Uredo corbiculoides.
Taxonomic novelties
Uredopeltis atrides (Syd. & P. Syd.) A.R. Wood. comb. nov. 相似文献
11.
Kuno Thomasson 《International Review of Hydrobiology》1980,65(5):745-747
A new subspecies of Keratella cochlearis, viz. Keratella cochlearis pachyacantka is described. It has been recorded from Africa and South America. 相似文献
12.
Marguerite Marquart 《Arts Education Policy Review》2013,114(2):33-36
A brief examination of early childhood music education in South Africa, through an investigation of government documents and academic literature, leads to an impression that music is embraced in a broad framework of meeting young children's cultural and artistic needs. There is an overriding consciousness of the value of providing children with connections to their cultural heritage and instilling in them appreciation for one another's cultures and respect for diversity. More specific policy for each age level of early childhood in several governmental departments is needed to protect children's voices and to ensure not only that their musical heritage and artistic creativity are nourished and fostered but also that we listen to what they say through their music. 相似文献
13.
BERNHARD A. HUBER 《Zoological Journal of the Linnean Society》2003,139(4):477-527
The southern African pholcid spiders previously assigned to Pholcus and Spermophora are revised and their phylogenetic position within Pholcidae is analysed cladistically. Two distinct groups are recognized: the first is restricted to the Cape region and probably correctly placed in Spermophora ; it includes Spermophora peninsulae Lawrence and four new species. The second is more widely distributed in southern and eastern South Africa, and reaches as far north as Cameroon, Congo (Democratic Republic) and Uganda; it is assigned generic status ( Quamtana gen. nov .), and includes two species transferred from Pholcus [ Q. leptopholcica (Strand), Q. ciliata (Lawrence)] as well as 23 new species. A key to the pholcid spiders of South Africa is presented. A close correlation between a male character (distance between cheliceral apophyses) and a female character (distance between pockets on epigynum) is documented in Quamtana . © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 139 , 477−527. 相似文献
14.
Wahlenbergia cordiformis, a new species of the Lightfootia‐type is described and illustrated. It is currently only known from the farm Knolfontein, in the Swartruggens region, north east of Ceres in the Western Cape, South Africa. The closest relative of W. cordiformis is unclear, but it may be closely related to either W. tenella, W. nodosa, W. tenerrima, W. oligantha or W. neorigida. Wahlenbergia cordiformis is distinguished from them by its cordate, leaf‐like calyx lobes. 相似文献
15.
Christopher C. Gilbert W. Scott McGraw Eric Delson 《American journal of physical anthropology》2009,139(3):421-429
Recent studies suggest a large raptor such as the crowned eagle (Stephanaoetus coronatus) was responsible for collecting at least a portion of the primate fauna from the South African fossil site of Taung, including its lone hominin specimen. This taphonomic signature at Taung is currently regarded as a unique and, most likely, isolated case in primate and human evolution. However, the activities of large, carnivorous birds should also be detectable at other primate fossil localities in Africa if raptors have been a strong selective force throughout primate evolution. Over the last 60 years, a collection of extinct cercopithecids has been assembled from several cave breccias on the Humpata Plateau in southern Angola. The material, dated near the Plio‐Pleistocene boundary, includes an assortment of craniodental and postcranial remains variably assigned to Papio (Dinopithecus) cf. quadratirostris, Parapapio, Cercopithecoides, and Theropithecus. We compare the Angolan and Taung material to remains of extant primates killed by crowned eagles in the Ivory Coast's Tai National Park. Our analysis indicates that the size distribution and composition of fauna from the localities is quite similar and that there are striking consistencies in damage to the crania from each site. The absence of large bodied (>20 kg) primates and other mammalian taxa at the Taung hominin locality and Tai, and their rarity in Angola, combined with the strong likelihood that raptor nests were positioned near fissure openings at both fossil localities, provides additional support for eagle involvement. On the basis of this evidence, we conclude that at least some of the Angolan cercopithecids were most likely raptor prey and hypothesize that raptor predation has been a strong and perhaps underappreciated selective force during the course of primate evolution. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc. 相似文献
16.
Large-scale comparisons might reveal matching between fruit traits and frugivore assemblages that might be cryptic on a local scale. Therefore, we compared morphological (colour, size, husk thickness) and chemical fruit traits (protein, nitrogen, sugar, lipid, tannin and fibre content) between Malagasy and South African tree communities with different frugivore communities. In Madagascar, where lemurs are important seed dispersers, we found more tree species with fruit colour classified as primate fruits. In contrast, in South Africa we found more tree species with fruits classified as bird coloured. This correlated with the greater importance of frugivorous birds in South Africa vs. Madagascar. Additionally, we found higher sugar concentrations in fruits from the South African tree community and higher fibre content in fruits from the Malagasy tree community. However, fibre content could be related to differences in abiotic conditions between the two study sites. This suggests that fruit colour more than other morphological and chemical fruit traits, reflects food selection by the different frugivore assemblages of those two sites. 相似文献
17.
18.
The fish populations within the East Kleinemonde Estuary, South Africa, were studied using Dual frequency IDentification SONar (DIDSON) during March 2010 which allowed for direct comparisons of the abundance, distribution and behaviour of a wide size range of fishes along the length of the system. Small schooling fishes <100 mm in total length (L(T) ) were most abundant while larger size classes 100-300 and 300-500 mm were less abundant, but evenly distributed longitudinally within the estuary. Fishes <100 mm were most abundant within the mouth region which may reflect the feeding ecology of species that fall into these size classes and the effects of higher turbidities further up the estuary. Large fishes >500 mm were similarly most abundant near the mouth, and fishes of this size being mostly piscivorous, probably showed these distribution patterns due to the location of smaller prey fishes. Differential behaviour was observed among the longitudinal sections, with small fishes forming schools in areas of low turbidity and particularly in the presence of large predatory fishes. Results from this study present a snap-shot of the composition, distribution and behaviour of the ichthyofauna within a small temporarily closed estuary, and also show that abiotic factors and interactions of various size classes can influence their distribution. There is significant potential for DIDSON in future ecological research within these systems. 相似文献
19.
Thembisa Waetjen 《Ethnic and racial studies》2013,36(4):653-678
In South Africa, a country in which the manipulation of ethnicity was at the heart of the government's attempts to establish control over the majority African population, ethnic mobilization during the liberation struggle was singularly unsuccessful. The one exception was Chief Mangosuthu Buthelezi's controversial Inkatha movement. This article suggests that one of the reasons for Inkatha's successes was the astute way in which the organization and, in particular, Buthelezi played on gendered notions of 'home' and 'homeland'. Historically, apartheid constructed notions of home and space differently for women and men and Inkatha was able to draw upon and manipulate these differences to produce a powerfully felt response. Thus, for men, many of them migrant workers in South Africa's cities, the notion of 'home' implied a return to patriarchal values and male domestic control in a historically constituted 'homeland'; for women, Buthelezi emphasized the new 'modern' opportunities opened up by the KwaZulu homeland, and the importance of their 'God-given' gifts of motherhood. 相似文献
20.
Morphological and metrical comparison of San and Central Sotho dentitions from southern Africa 总被引:1,自引:0,他引:1
A M Haeussler J D Irish D H Morris C G Turner 《American journal of physical anthropology》1989,78(1):115-122
Comparative morphological and metrical study of San and Central Sotho dentitions indicates that the teeth of the two samples are significantly different from one another. The San dental complex contains traits that add mass to the occlusal surface of microdontic dentitions: moderate low-grade UI1 (13.5%) and UI2 shoveling (24.7%), high Bushman canine (43.1%), fairly low UM2 hypocone reduction (23.3%), high UM2 cusp 5 (55.6%), high LM1 cusp 7 (35.2%), LM1 distal trigonid crest (7.1%), and LM2 deflecting wrinkle (5.3%), lack of reduction of LM1 and LM2 cusp number, in the presence of very low UM1 Carabelli's trait (6.7%) and high LM2 Y-groove (86.3%). Culturally, males occasionally exhibit filed UI1 and females are missing LI1. Conversely, mesodontic Central Sotho dentitions display a more simplified morphology, with the exception of moderately high incidence of UM1 Carabelli's trait (41.0%) and very high LM1 cusp 7 (71.3%). Discriminant analysis of mesiodistal and buccolingual diameters and tooth crown surface area data for the left maxillary teeth supports classification of San dentitions as microdont and Central Sotho dentitions as mesodont. Additionally, metrical analysis indicates that San teeth are more sexually dimorphic than are those of Central Sotho. 相似文献