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1.
R G Klein G Avery K Cruz-Uribe D Halkett T Hart R G Milo T P Volman 《Journal of human evolution》1999,37(2):153-190
Excavations at Duinefontein (DFT) 2 near Cape Town, South Africa have recovered numerous stone artefacts and animal bones on an ancient surface sealed within iron-stained eolian sands. U-series analysis of an overlying calcrete places the sands before 150 ka ago, while the large mammal taxa imply an age between 400 and 200 ka ago. The artefacts include a classic Acheulean handaxe and probable biface shaping flakes that support this age estimate. The principal mammalian species are long-horned buffalo, black wildebeest, greater kudu, Cape zebra, and grysbok/steenbok, which imply a grass-and-bush mosaic instead of the historic small-leafed shrubland.Hippopotamus and reedbuck indicate that water stood nearby, probably in dune swales. The large mammal bones are mostly vertebrae and other axial elements, often in near-anatomical order. Both proximal and distal appendicular elements are rare. Bones with carnivore damage are common, but ones with stone tool marks are scarce. The sum suggests a water-edge attritional death site where people played a minimal role and carcasses were disarticulated mainly by carnivore feeding and by trampling. Stone tool marks tend to be equally rare at other Acheulean attritional death sites, and the implication may be that Acheulean people rarely obtained large mammals, whether by hunting or scavenging. Human scavengers at DFT2 would not have encountered a disproportionate number of distal (versus proximal) limb elements, and it follows that the tendency for distal elements to dominate many archeological assemblages need not reflect scavenging versus hunting. Even if DFT2 was not itself a locus of intense human activity, it provides a useful baseline for evaluating bone damage, skeletal part representation, and other variables at sites where people were deeply involved. 相似文献
2.
Ryan J. Gibbon Darryl E. Granger Timothy C. Partridge 《Journal of human evolution》2009,56(2):152-160
An absolute dating technique based on the build-up and decay of 26Al and 10Be in the mineral quartz provides crucial evidence regarding early Acheulean hominid distribution in South Africa. Cosmogenic nuclide burial dating of an ancient alluvial deposit of the Vaal River (Rietputs Formation) in the western interior of South Africa shows that coarse gravel and sand aggradation there occurred ca 1.57 ± 0.22 Ma, with individual ages of samples ranging from 1.89 ± 0.19 to 1.34 ± 0.22 Ma. This was followed by aggradation of laminated and cross-bedded fine alluvium at ca 1.26 ± 0.10 Ma. The Rietputs Formation provides an ideal situation for the use of the cosmogenic nuclide burial dating method, as samples could be obtained from deep mining pits at depths ranging from 7 to 16 meters. Individual dates provide only a minimum age for the stone tool technology preserved within the deposits. Each assemblage represents a time averaged collection. Bifacial tools distributed throughout the coarse gravel and sand unit can be assigned to an early phase of the Acheulean. This is the first absolute radiometric dated evidence for early Acheulean artefacts in South Africa that have been found outside of the early hominid sites of the Gauteng Province. These absolute dates also indicate that handaxe-using hominids inhabited southern Africa as early as their counterparts in East Africa. The simultaneous appearance of the Acheulean in different parts of the continent implies relatively rapid technology development and the widespread use of large cutting tools in the African continent by ca 1.6 Ma. 相似文献
3.
A survey of nematodes associated with native and introduced species of terrestrial slugs was conducted in the Western Cape Province of South Africa, in order to gather new data regarding diversity and distribution. A total of 521 terrestrial slugs were collected from 35 localities throughout the Western Cape. All slugs were dissected and examined for the presence of internal nematodes. Extracted nematodes were identified using a combination of molecular (18S rRNA gene sequencing) and morphological techniques. Nematodes were found parasitizing slugs at 14 of the 35 sites examined, amounting to 40% of sample sites. Of all slugs, 6% were infected with nematodes. A total of seven species of nematode were identified in the province, including Agfa flexilis, Angiostoma sp., Phasmarhabditis sp. SA1, Phasmarhabditis sp. SA2, Caenorhabditis elegans, Panagrolaimus sp. and Rhabditis sp. Of these species, four were thought to be parasitic to slugs (A. flexilis, Angiostoma sp., Phasmarhabditis sp. SA1 and Phasmarhabditis sp. SA2), as opposed to forming necromenic or phoretic associations. Three new species of slug-parasitic nematode were identified during this study (Angiostoma sp., Phasmarhabditis sp. SA1 and Phasmarhabditis sp. SA2). 相似文献
4.
J C Sealy M K Patrick A G Morris D Alder 《American journal of physical anthropology》1992,88(2):123-134
Stable carbon isotope measurements and incidences of dental caries are presented for three groups of prehistoric human skeletons from different regions of the Cape Province, South Africa. The isotopic analyses of bone collagen demonstrate the importance of marine foods in the diet and vary through time, across space, and according to sex. The incidence of dental caries ranges from 0% among heavily marine-dependent individuals from the south-western Cape coast, to 17.7% among skeletons from an archaeological site on the south coast. The extremely high incidence of caries in a hunter-gatherer population may be related to lack of fluoride in the water. 相似文献
5.
《Ostrich》2013,84(4):275-284
Bi-monthly counts of waterbirds were made between March and September 2003 at an ephemeral pan in the Northern Cape Province following the first substantial inundation since 1988. Bi-annual counts between 1991 and 2003 indicated that the pan infrequently supported waterbirds, with waterfowl and small waders generally being the dominant species. During the bimonthly counts, a total of 50 waterbird species was recorded, with the most dominant species, both in terms of numbers and duration of presence, being Black-winged Stilt Himantopus himantopus (max. 378), Cape Shoveller Anas smithii (max. 260) and South African Shelduck Tadorna cana (max. 200). Most other waterfowl and wader species were regular but in lower numbers. Species groups that occurred in limited numbers or for short periods include primarily herons, grebes, flamingos, ibises and storks. Species abundance and richness reached a peak one month after the pan was inundated, followed by a gradual decline over the ensuing two months. 相似文献
6.
Waterbird assemblages and associated habitat characteristics of farm ponds in the Western Cape, South Africa 总被引:4,自引:0,他引:4
Albert Froneman Michael J. Mangnall Robin M. Little Timothy M. Crowe 《Biodiversity and Conservation》2001,10(2):251-270
Natural freshwater wetlands are among the most threatened habitats on Earth. Effective wetland biodiversity conservation can not, however, be evaluated without fully understanding the roles of artificial waterbodies as refuges for water-dependent plants and animals. Waterbird assemblages were examined on 59 farm ponds in the Elgin and Caledon districts of the Western Cape, South Africa. This study examines the relationship between waterbird use and habitat characteristics of farm ponds. Patterns of temporal and spatial variation of waterbird species richness and abundance were quantified in relation to the habitat characteristics of each pond. Cluster analysis and multiple regression analyses identified surface area of the farm ponds as an important variable determining the presence and abundance of many waterbird species. Structural diversity in terms of vegetation in and around the ponds was especially important in determining their usage by waterbirds. These variables were evaluated in terms of creating a mosaic of habitat types (by varying vegetation structure and pond topography), which may be a useful way to enhance waterbird diversity at farm ponds. This study concludes that the high number of farm ponds in the transformed habitat matrix of the Western Cape plays an important role in conserving waterbirds. 相似文献
7.
Marean CW 《Journal of human evolution》2010,59(3-4):425-443
Genetic and anatomical evidence suggests that Homo sapiens arose in Africa between 200 and 100ka, and recent evidence suggests that complex cognition may have appeared between ~164 and 75ka. This evidence directs our focus to Marine Isotope Stage (MIS) 6, when from 195-123ka the world was in a fluctuating but predominantly glacial stage, when much of Africa was cooler and drier, and when dated archaeological sites are rare. Previously we have shown that humans had expanded their diet to include marine resources by ~164ka (±12ka) at Pinnacle Point Cave 13B (PP13B) on the south coast of South Africa, perhaps as a response to these harsh environmental conditions. The associated material culture documents an early use and modification of pigment, likely for symbolic behavior, as well as the production of bladelet stone tool technology, and there is now intriguing evidence for heat treatment of lithics. PP13B also includes a later sequence of MIS 5 occupations that document an adaptation that increasingly focuses on coastal resources. A model is developed that suggests that the combined richness of the Cape Floral Region on the south coast of Africa, with its high diversity and density of geophyte plants and the rich coastal ecosystems of the associated Agulhas Current, combined to provide a stable set of carbohydrate and protein resources for early modern humans along the southern coast of South Africa during this crucial but environmentally harsh phase in the evolution of modern humans. Humans structured their mobility around the use of coastal resources and geophyte abundance and focused their occupation at the intersection of the geophyte rich Cape flora and coastline. The evidence for human occupation relative to the distance to the coastline over time at PP13B is consistent with this model. 相似文献
8.
Marean CW Bar-Matthews M Fisher E Goldberg P Herries A Karkanas P Nilssen PJ Thompson E 《Journal of human evolution》2010,59(3-4):234-255
Pinnacle Point Cave 13B (PP13B) has provided the earliest archaeological evidence for the exploitation of marine shellfish, along with very early evidence for use and modification of pigments and the production of bladelets, all dated to approximately 164?ka (Marean et?al., 2007). This makes PP13B a key site in studies of the origins of modern humans, one of a handful of sites in Africa dating to Marine Isotope Stage 6 (MIS 6), and the only site on the coast of South Africa with human occupation confidently dated to MIS 6. Along with this MIS 6 occupation there are rich archaeological sediments dated to MIS 5, and together these sediments are differentially preserved in three different areas of the cave. The sediments represent a complex palimpsest of geogenic, biogenic, and anthropogenic input and alteration that are described and interpreted through the use of a variety of macrostratigraphic, micromorphologic, and geochemical techniques. Three independent dating techniques allow us to constrain the age range of these sediments and together provide the stratigraphic context for the analyses of the material that follow in this special issue. 相似文献
9.
The extensive early Pliocene mammalian assemblages at Langebaanweg hold the potential to provide important information about paleoenvironments of the southwestern tip of Africa, an area that today consititutes the Fynbos Biome. We here add to a growing body of literature on the paleoenviornments of the site with an examination of dental microwear textures of bovids from the Varswater Formation. Microwear texture analysis is a new, automated and repeatable approach that measures whole surfaces in three dimensions without observer error. A study of extant ruminants indicates that grazers have more anisotropic microwear surface textures, whereas browsers have more complex microwear surface textures. Fossil bovids recovered from the Muishond Fontein Pelletal Phosphorite Member vary in their microwear textures, with some taxa falling within the extant browser range, some closer to extant grazers, and others in between. These results are consistent with scenarios suggesting mosaic habitats including fynbos vegetation, some (probably C3) grasses, and woodland elements when these fossils were accumulated. 相似文献
10.
Current and future threats to plant biodiversity on the Cape Peninsula, South Africa 总被引:3,自引:0,他引:3
D. M. Richardson B. W. van Wilgen S. I. Higgins T. H. Trinder-Smith R. M. Cowling D. H. McKell 《Biodiversity and Conservation》1996,5(5):607-647
The biodiversity of the Cape Peninsula (49127 ha in extent) has been considerably affected by various factors since European settlement in 1652. Urbanization and agriculture have transformed 37% of the original area of natural vegetation. Lowland vegetation types have been worst affected, with almost half of the transformation occurring in one of the 15 recognized vegetation types. Vegetation at high altitudes has been little affected by urbanization and agriculture, but alien trees and shrubs are now threatening biodiversity in these areas. Of the area not affected by urbanization and agriculture 10.7% is currently under dense stands (>25% canopy cover) of alien plants and another 32.9% is lightly invaded. Dense stands of Acacia cyclops, the most widespread invader, cover 2510 ha, 76% of the total area under dense alien stands. This paper assesses the impacts of these factors on aspects of the plant biodiversity of the area, namely, the distribution of major vegetation types and of endemic, rare and threatened plant taxa and of taxa in the Proteaceae (a prominent element in almost all communities, taken as an indicator of overall plant biodiversity).Possible future impacts on biodiversity are assessed by considering the effects of several scenarios involving increased urbanization and changes to alien plant control strategies and further spread over the next 50–100 years. The worst-case scenario for urbanization sees the area under natural vegelation reduced to 12163 ha (39.3% of its extent in 1994, or 24.8% of its original extent). Under this scenario almost a quater of the 161 endemic, rare and threatened (special) taxa are confined totally to urban areas; 57.4% of the known localities of these taxa, and 40.1% of the remaining localities of Proteaceae taxa are transformed. Dense alien stands currently affect 29.8% of the localities of special taxa known from herbarium records and 8.4% of these taxa currently occur only in areas at present affected by aliens. Clearing all dense stands would result in 62.9% of special taxa having less than half of their known localities affected (49.1% at present). Under this scenario, 92% of Proteaceae taxa have more than 75% of their localities unaffected by aliens. If clearing is confined to specific areas (the Cape Peninsula Protected Natural Environment or all publicly-owned land) and the aliens spread further outside these areas, the area of natural vegetation remaining shrinks (to 82.4% of the current extent if control is confined to public land). The further losses in biodiversity associated with these scenarios are described. If control programmes collapse and all potentially invadable land is occupied by dense alien stands, only 407 ha of natural vegetation would remain (1.5% of the current extent).The probability of the various scenarios materializing is discussed. To minimize further losses in biodiversity it is essential that: (1) a major initiative is launched immediately to clear (firstly) the 10184 ha of lightly invaded vegetation and then the 3313 ha of densely invaded vegetation; (2) no urban development be permitted within the boundaries of the Cape Peninsula Protected Natural Environment; (3) a systematic programme of prescribed burning (linked to the alien control programme) is initiated; and (4) contingency measures are implemented to improve the status of seriously threatened taxa, habitats and vegetation types. 相似文献
11.
12.
Fred Kigozi 《African Journal of Ecology》2003,41(4):289-293
South Africa is considered one of the top four chicory (Chichorium intybus) producing countries of the world and commercial growing of the plant in the country is restricted to a small area in three districts of the Eastern Cape Province. Faecal analysis technique was used to study the diet of common duiker (Sylvicapra grimmia Linnaeus, 1758) in a chicory growing region at Grants valley. One of the principal items in the diet of these antelopes was chicory and the crop provided more than one third (35.6%) of the winter diet and a substantial proportion (14.4%) of the spring diet of common duiker. These findings confirmed earlier reports of common duiker feeding on cultivated crops and may have profound implications for the South African chicory industry. The study also confirmed earlier findings that common duiker are selective feeders and predominantly browsers, consuming only a very small proportion of monocotyledonous plants. 相似文献
13.
《Journal of bryology》2013,35(4):234-239
AbstractA new genus, Acaulonopsis (Pottiaceae, Bryophyta), including two new species, A. fynbosensis and A. eureka, is described from the Western Cape Province of South Africa. Together with the similarly much reduced pottiaceous genus Acaulon, Acaulonopsis is unique in the family with a very short seta and spherical capsule, which lacks the apiculus found in other genera. The new genus is also distinguished by short plant stature, and a total of about five ovate leaves that clasp closely the capsules in nearly spherical leaf bases. Continuing bryological study of the fynbos region has recently resulted in a number of startling discoveries of bryophytes new to science and distinct at the genus level. A new combination is made for the South African endemic genus Vrolijkheidia (Pottiaceae) with discussion of its dimorphic habitus. 相似文献
14.
Site PP13B is a cave located on the steep cliffs of Pinnacle Point near Mossel Bay in Western Cape Province, South Africa. The depositional sequence of the cave, predating Marine Isotopic Stage 11 (MIS 11) and continuing to present, is in the form of isolated sediment exposures with different depositional facies and vertical and lateral variations. Micromorphological analysis demonstrated that a suite of natural sedimentation processes operated during the development of the sequence ranging from water action to aeolian activity, and from speleothem formations to plant colonization and root encrustation. At the same time, anthropogenic sediments that are mainly in the form of burnt remains from combustion features (e.g., wood ash, charcoal, and burnt bone) were accumulating. Several erosional episodes have resulted in a complicated stratigraphy, as discerned from different depositional and post-depositional features. The cave is associated with a fluctuating coastal environment, frequent changes in sea level and climate controlled patterns of sedimentation, and the presence or absence of humans. 相似文献
15.
The distribution and state of mangroves along the coast of Transkei,Eastern Cape Province,South Africa 总被引:1,自引:0,他引:1
The mangrove communities along the coastline of the former Transkei, now part of the Eastern Cape Province, have not been looked at in detail since Ward and Steinkes survey in 1982. Mangroves previously occurred in 17 estuaries but were now found in only 14 of the 76 estuaries visited, with a complete loss of mangroves evident in the Mnyameni, Mzimvubu and Bulungula estuaries amounting to 7.5 ha. Total mangrove loss amounted to 17.6 ha which represents a 6.5% loss over 17 years or 1.04 ha per annum. Tree cover had increased by 16.15 ha in eight other estuaries. This increase could be attributed to the inaccessibility of mangrove stands or to protection afforded by provincial nature reserves and hotel resorts. No new mangrove stands were recorded, although Steinke (pers. comm.) has recently recorded mangroves along the north bank of the Kei River. There has been little change in mangrove species composition in the different estuaries over the past 17 years. Total mangrove loss amounted to 17.6 ha which represents a 6.5% loss over 17 years or 1.04 ha per annum and the species recorded included Avicennia marina, Bruguiera gymnorhiza and Rhizophora mucronata. The mangrove fern Acrostichum aureum L. was recorded for the first time in the Mkozi estuary. Tree density for all estuaries was between 10 and 2594 trees ha–1. The Mngazana and Mntafufu estuaries had the highest tree densities of 2594 and 1402 trees ha–1 respectively, typical of riverine mangrove forests. Fringe mangroves were evident in most other systems. Removal of trees for wood has the greatest impact on mangrove cover. Fringe mangrove stands are particularly accessible to harvesters. Only 6% of the current area of trees is afforded some protection in conservation areas. The Mdumbi, Mzamba and Kobonqaba estuaries receive no conservation protection and harvesting has resulted in more than 50% of the trees being removed. The density of dead tree stumps was greater than the number of living trees and no seedlings or juvenile trees were found. Further removal of mangroves within the estuaries south of the Mzimvubu River is expected in the fringe mangroves, as most are unprotected and easily accessible. 相似文献
16.
The effects of agriculture on farmland bird assemblages on the Agulhas Plain, Western Cape, South Africa 总被引:1,自引:0,他引:1
Coastal Fynbos on the Agulhas Plain of the Western Cape, South Africa, has been transformed extensively by crop and pastoral agriculture. Many bird species, e.g. sunbirds, nightjars and mousebirds have consequently been affected negatively by the reduction of suitable habitat for daily requirements. However, populations of certain bird species, especially granivores and omnivores, such as sparrows, larks and pipits, as well as Egyptian Geese and Helmeted Guineafowl have proliferated on the Agulhas Plain. This study investigates the effects of agricultural development on overall bird diversity on the Agulhas Plain. In 1998, twice monthly transect counts at 13 farmland sites recorded 106 bird species. Fifteen species occurred at 75% or more of the sites. Highest avian diversity was recorded at the sites with a mixture of crops and Coastal Fynbos (Mixed regime). A small number of species, e.g. sunbirds, are reliant on the natural Coastal Fynbos for their survival. With the exception of the Mixed regime that gained 50 species, all the other agricultural regimes reflected a loss of diversity when compared with Fynbos. To provide more suitable habitat for a greater diversity of birds, mixed landscapes should be maintained, and further destruction of natural Fynbos habitat should be prevented. 相似文献
17.
Michael J. Lawes Harriet A.C. Eeley Steven E. Piper 《Biodiversity and Conservation》2000,9(5):683-705
The relationship between local and regional diversity was tested by regressing local community richness against regional species diversity for three taxa, birds, butterflies and mammals, in subtropical forest. The quadratic model best fits the relationship between local and regional diversity for birds. Local bird species richness is theoretically independent of the size of the regional pool of species and may represent saturated communities. A linear model best describes the relationship for mammals and butterflies. For mammals, the slope is shallow (0.264) and regional richness overestimates local species richness, suggesting communities are undersaturated. Extinction filtering may explain this pattern. Past climatic changes have filtered out many mammalian species, these changes have been too recent for autochthanous speciation, and the relatively low vagility of mammals has prevented extensive recolonisation. Differences in the nature of the diversity relationship between taxa are as much due to independent evolutionary histories as to differences in vagility and colonising potential. A pervasive role is suggested for regional biogeographic processes in the development of faunal assemblage structure. Large-scale processes are not considered in current conservation plans. We encourage the shift of conservation emphasis from local ecological processes and species interactions, to whole communities and consideration of regional processes. 相似文献
18.
Die Kelders Cave 1, first excavated under the direction of Franz Schweitzer in 1969-1973, was re-excavated between 1992 and 1995 by a combined team from the South African Museum, SUNY at Stony Brook, and Stanford University. These renewed excavations enlarged the artefactual and faunal samples from the inadequately sampled and less intensively excavated lower Middle Stone Age (MSA) layers, increased our understanding of the complex site formation processes within the cave, enlarged the hominid sample from the MSA deposits, and generated ESR, TL, and OSL dates for the MSA layers. Importantly, these new excavations dramatically improved our comprehension of the vertical and lateral characteristics of the MSA stratigraphy. Surface plotting of the MSA layers has led to the identification of at least two major zones of subsidence that significantly warped the layers, draping some along the eroding surface contours of major blocks of fallen limestone roof rock. A third zone of subsidence is probably present in the older excavations. Dramatic roof falls of very large limestone blocks occurred at least twice-once in the middle of Layer 4/5 where the roof blocks were only slightly weathered after collapse, and at the top of Layer 6 where the blocks weathered heavily after collapse, producing a zone of decomposed rock around the blocks. Many of the sandy strata are cut by small and localized faults and slippages. All of the strata documented by Schweitzer's excavations are present throughout the exposed area to the west of his excavated area, where many of them thicken and become more complex. Layer 6, the thickest MSA layer, becomes less diagenetically altered and compressed to the west. 相似文献
19.
Some of the earliest evidence for modern human behavior has been recovered from the Western Cape Province, South Africa. Archaeological and paleontological sites in the Western Cape are typically described as “glacial” or “interglacial” in aspect based on the numbers of grazers found in the faunal assemblage, as glacial periods are often thought to have been characterized by spreading C4 grasslands that replaced endemic C3 shrubland vegetation found in the Western Cape today. Here, we test the hypothesis that glacial and interglacial time periods were associated with a predictable change in large mammal trophic adaptations by analyzing the proportions of grazing larger mammals from 118 levels of 15 Western Cape fossil assemblages sampling marine isotope stage (MIS) 6 to the present time to determine whether there is a change in composition in these communities that might reflect a shift in ecology and habitat. Our results indicate that trophic proportions did not significantly change over time in the Western Cape as a whole, and thus the hypothesis for habitat changes affecting the subsistence ecology of modern humans during the development of modern behavior is not supported. However, our results show that the southwestern subregion of the Western Cape was characterized by the presence of more grazing species through time than the western subregion. Thus, if ecological and population isolation during glacial periods were integral to catalyzing the development of modern behaviors in the Western Cape region of South Africa, then a complex model including the development of possible mosaic habitats is needed. 相似文献
20.
The Hollow Rock Shelter site in Western Cape Province, South Africa, was excavated in 1993 and 2008. This study presents new results from a technological analysis of Still Bay points and bifacial flakes from the site. The results show that Still Bay points from the site are standardized tools. The points in the assemblage consist of a complex mixture of whole and fragmented points in all phases of production. The fragmentation degree is high; approximately 80% of the points are broken. A high proportion of bending fractures shows that several of the points were discarded due to production failures, and points with impact damage or hafting traces show that used points were left in the cave. This illustrates that the production of points as well as replacement of used points took place at the site. The result also shows that worked but not finished preforms and points were left at the site, suggestive of future preparation.The points were produced within the framework of three different chaînes opératoires, all ending up in a typologically uniform tool. This shows that the manufacture of Still Bay points should be regarded as a special bifacial technology, only partly comparable with other bifacial technologies. A raw material analysis shows that locally available quartz and quartzite were used in the production, and that points made of silcrete were brought to the site.Based on the technological analysis, a discussion of behavioural modernity, focusing on hypotheses about social interaction, experimentation, different strategies for learning to knap, and landscape memories, results in an interpretation that behavioural modernity was established at Hollow Rock Shelter in the Still Bay phase of the southern African Middle Stone Age. 相似文献