Volume 23 1980
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- ItemSwartkrans as a case study in African cave taphonomy(Bernard Price Institute for Palaeontological Research, 1980) Brain, C. K.By taphonomy is meant the systematic study of death assemblages of once-living things in this case of vertebrate animals. Such study may have various aims but in the present instance my objective has been the interpretation of bone assemblages in the Swartkrans cave to throw light on such topics as: 1. the ways in which bones found their way to the cave; 2. the nature of the animal communities which contributed bones to the assemblages and the kind of environment in which the communities lived; 3. the behaviour of the hominids and other animals whose bones form part of the fossil assemblage. Swartkrans, though not a particularly large cave, is one of considerable complexity and can be used as a case study to illuminate several principles in African cave taphonomy. Three of these principles are discussed.
- ItemFaunal remains from Hot Pot Cave, Bredasdorp(Bernard Price Institute for Palaeontological Research, 1980) Gow, C. E.Recent unconsolidated cave deposits can be useful in providing an understanding of how consolidated fossil cave deposits were formed and are far easier and quicker to analyse. This preliminary study describes an extensive, extremely rich bone accumulation in a horizontal cave system linked to the surface by a single verticaI shaft from the middle of a domed chamber. The cave is in Tertiary marine limestone on the southwestern Cape coast. The fauna has two chief components: a macrofauna resulting from entirely fortuitous introductions such as animals falling down the shaft; and an extensive microfauna accumulated by the barn owl, Tyto alba. Between these two groups there is a very small range of possible overlap. The macrofauna contains a mixture of wild and domestic animals, herbivores and predators with sizes ranging from hare to buffalo. The microfauna is closely packed in a black organic-rich soil of predominantly dust sized particles. A feature of this soil is the vast number of tiny terrestrial snail shells it contains. The deposit represents continuous accumulation over several hundred years at least. Seeds, pollen and carbonised wood are present in the undisturbed deposit so that sequential dating will be possible. By contrast, recognisable insect cuticle is virtually absent though dung beetles, for example, are frequently seen in surface solution cavities and must fall into the cave in fair numbers. Alignment of microfauna! longbones within the deposit is horizontal and parallel to the passage walls, so it is clear that the material was distributed by stream action. Much of the fauna has a wide geographic range, but throughout there are elements either endemic to the southern Cape or indicative of the prevailing vegetation type.
- ItemThe nature and genesis of solution cavities (Makondos) in Transvaal Cave breccias(Bernard Price Institute for Palaeontological Research, 1980) Brink, A. B. A.; Partridge, T. C.The discovery of a large part of the cranium of a hominid, evidently closely related to Homo habilis (Hughes and Tobias 1977) in a solution cavity within the calcified Member 5 of the Sterkfontein Formation (Partridge 1978) has again drawn attention to the frequent occurrence of these features in the hominid-bearing breccias of the Transvaal. The authors first studied these features at Makapansgat (fig. 1) some fifteen years ago and have since then become aware of their very widespread occurrence in soluble rocks in many parts of the world. All subsequent information has served to confirm the origin of these features, but, since these were never published, it is worthwhile to place these findings on record. Solution cavities, or Makondos, in the Transvaal cave breccias are soil-filled pits shaped like an inverted cone. Their walls and intervening areas of the calcified cave deposit are usually rough, and the coalescing of adjacent cavities below the surface is common. They seldom exceed 2 m in diameter and 6 m in depth and occur at intervals of 2 to 3 m in the calcified cave deposit.
- ItemBone collecting by striped hyaenas, Hyaena hyaena, in Israel(Bernard Price Institute for Palaeontological Research, 1980) Skinner, J. D.; Davis, S.; Ilani, G.Differences in bone collecting behaviour of three species of hyaena and porcupines are discussed. Observations on feeding behaviour of striped hyaenas are described as well as their habit of carrying pieces away particularly if feeding cubs at maternity dens. At one maternity den near Arad the floor of the main cavern was littered with bones which covered an area of 40 m2. Of this 2,0 m2 was sampled and found to contain 267 bones and bone fragments from no fewer than 57 individuals, mainly of domestic species such as camel, donkey, caprovines and dogs.
- ItemCarnivore damage to antelope bones and its archaeological implications(Bernard Price Institute for Palaeontological Research, 1980) Richardson, P. R. K.The rates of survival, damage, fragmentation and degree of articulation of the bones of 89 bovids eaten by a variety of carnivores in the Transvaal are presented and evaluated. These results are entirely predictable considering the size, density, shape and mode of attachment of the bones. With the exception of the brown and spotted hyaenas the extent of damage to these bones can be directly related to the sizes of the bovids and the carnivores concerned. The hyaenas have disproportionately high abilities to crush bones, particularly the long limb bones. The bones all had fairly uniform survival rates except the ribs, carpals, tarsals, phalanges and caudal vertebrae, which are easily eaten or removed. Mandibles and scapulae had exceptionally low articulation rates, and long bones, crania and ribs had the highest fragmentation rates. Small bovid bones were far more susceptible to damage by trampling than those of larger bovids. Certain differences between carnivore and hominid damage to bones are mentioned. These relate primarily to hominids using their hands to dismember and damage bones selectively, particularly long bones which are broken in half to extract the marrow. A different pattern of survival of long bone epiphyses resulting from hominid activity can be predicted from that caused by carnivores, especially hyaenas. The pattern of survival of epiphyses at Makapansgat is that predicted for hominids, whereas the pattern at Swartklip I, an accepted hyaena site, is the opposite. It is therefore suggested that australopithecines were the primary bone collectors at Makapansgat. Further data on the differences between carnivore and hominid damage are also presented.
- ItemAn overview of palaeomagnetic chronology with special reference to the South African hominid sites(Bernard Price Institute for Palaeontological Research, 1980) McFadden, P. L.The phenomena of secular variation, polarity reversals and apparent polar wander are discussed. The calibration of each of these phenomena for use in palaeomagnetic chronology is outlined and the use of each of these calibrated scales for dating is briefly explained. A successful application of the polarity reversal dating technique is presented as an example of the potential for palaeomagnetic chronology in South Africa. In this example it is shown that the age of the important Member 3 in Makapan is about 3 My. It is concluded that palaeomagnetic chronology has a vast potential in South Africa ; a palaeomagnetic laboratory specifically oriented to chronological problems would be extremely valuable.
- ItemModels in geomorphology- Quaternary evolution of the actual relief pattern of coastal central and northern Namib desert(Bernard Price Institute for Palaeontological Research, 1980) Rust, U.Field and laboratory results gained at various SWA/Namibian sites between the Kuiseb river in the south and the Unjab river in the north are presented. At the Namib coast under study two low stands of sea level and two high stands, one of them of Intra-Wurmian age, can be proved. From Toscanini northward a third (? Holocene) high stand exists besides the other two. The former shore lines can be linked spatially and temporally to the terrestrial relief sequences by means of fluvial and eolian land forms and sediments. Thus the changing patterns of more arid or more humid environments at different morphoclimatic stages up to the present one can be described. Furthermore, it is evident that the geomorphic processes themselves change regionally, and it is seen that the Central Namib desert is a geomorphologically unique area in comparison with the Skeleton Coast and the southern dune area. Finally, the tendencies of Quaternary landscape evolution even enable us to deduce some geoecological consequences concerning man's activities in this desert.
- ItemLast integral shorelines in the South Cape(Bernard Price Institute for Palaeontological Research, 1980) Davies, OliverMy paper discusses the Last Interglacial shorelines of the South Cape with reference to findings from the rest of the world. I call them Eemian shorelines, and define Eem as an interglacial with three peaks of sea level separated by two stadials when the ocean dropped. I use the term Eem though it has been wrongly applied in north-west Europe (Kukla 1977). Other names have been given to this interglacial; in the deep-ocean record the stage is referred to as Stage X or Stage 5. It has been dated mostly by Uranium/Thorium as lasting from about 125 000 to 80 000 B.P. The dates and the fluctuations will be discussed below
- ItemDune systems an palaeoenvironments in southern Africa(Bernard Price Institute for Palaeontological Research, 1980) Lancaster, N.Extensive systems of fixed linear dunes occur throughout the Kalahari. Together the dunes form a semicircular arc with a radius of 1 000 km which corresponds approximately with the pattern of outblowing winds around the South African anticyclone. The dunes were formed by a wind regime broadly similar to that existing today. However, differences between dune alignments and present-day potential resultant sand flows in the northern part of the system suggest that shifts in the position and strength of the South African anticyclone may have taken place since these dunes were formed. Comparison of the extent of fixed dunes with that of the presently active dunes indicates that the extent of the arid zone in southern Africa has altered substantially in the past. Evidence exists for at least two periods of much greater aridity in the subcontinent, but their dating remains uncertain.
- ItemTertiary environmental changes along the south-western African coast(Bernard Price Institute for Palaeontological Research, 1980) Coetzee, J. A.Evidence for major vegetation and climatic changes during the Tertiary in the south-western Cape has been obtained from a number of sites. The palynomorph assemblages indicate in general an alternation of relatively cool temperate forests with two periods of subtropical - tropical palm-dominated vegetation from the Late Oligocene/ Early Miocene to the Pliocene when many of the taxa became extinct. Subsequently, strong development of macchia vegetation took place. These changes can be correlated with some palaeogeographic data and the major temperature changes of the Southern Ocean indicated in the palaeotemperature curve of Shackleton and Kennett (1975) which reflects the longterm progressive cooling of the earth since the Eocene/Oligocene boundary. The two subtropical- tropical periods can probably be related to the respective Early and Middle Miocene pan-African faunas of Arrisdrift and Luderitz and could coincide with the two warmest periods of the Miocene at 19 My and 14 My ago. The end of the Miocene witnessed the maximum build-up of the Antarctic icesheet and the substantial increase of the upwelling in the Benguela Current. This resulted in the initiation of the aridification of the present Namib desert, the extermination of the palm vegetation and the provincialism of the coastal molluscs. The important drop in temperature which reached its maximum about 3,5 My ago in the Pliocene could have exterminated the surviving elements of the last of the temperate Tertiary forests. The progressive aridity of the continent resulted in the spread of savannas, the evolution of the Alcelaphini and Antelopini and the change to regional vertebrate faunas. The increasing summer aridity in the southwestern Cape led to the strong development of the macchia vegetation.
- ItemSedimentological characteristics of the "red muds" at Makapansgat Limeworks(Bernard Price Institute for Palaeontological Research, 1980) Turner, Brian R.The "red muds" which occur at Rodent Corner along the west face of the exit quarry at Makapansgat limeworks have been divided into two sedimentary facies according to lithology, sedimentary properties and biological content: (1) coarse sandstone; and (2) siltstone and fine-sandstone. These two facies form a depositional couplet or sedimentary motif that occurs throughout the deposits and can be used as a basis for interpretation of the conditions of deposition. The coarse sandstone facies consists of thin lenticular beds which contain occasional elongate bone fragments showing a pronounced sedimentary fabric. This facies was probably deposited by flowing water, but, because of its coarse grain size, scale and low granulometric contrast, traction current structures such as cross-bedding and ripple cross-lamination were not developed. The angular character of the individual grains implies a short distance of transport and local derivation of the facies. The siltstone and fine sandstone facies is red and calcareous and contains sporadically distributed coarse sand grains. It is generally thicker and laterally more persistent than the coarse sandstone facies and capped by a mudcracked surface. The general characteristics of this facies are consistent with deposition in slow-moving or standing water from quiet suspension sedimentation. Shallowing of the water, related to changes in level of the water table, led to exposure of the depositional surface and the development of mudcracks. A variation of this facies pattern occurs in the middle of the succession where two limestone layers were deposited, the upper one intimately associated with local concentrations of cave pearls which originated from the lime-rich surface waters in locally agitated pools by concentration and precipitation of carbonate about a central nucleus. The facies couplet is interpreted in terms of storm and fair weather processes and compared with modern analogues found on shallow marine shelves, alluvial plains and in lakes. The coarse sandstone facies is attributed to storms and heavy rainfall outside the cave washing in coarse sandy detritus and raising the level of the water table. Between storm episodes quiet suspension sedimentation occurred accompanied by a gradual shallowing of the water table. Thus the coarse sandstone facies provides clues to storm periodicities and rainfall and suggests a rather wet climatic regime at this time. The red muds at Rodent Corner differ from those near the "Ancient Entrance" in that they contain coarse sandy interbeds, implying that the two deposits were separated from one another, possibly by a floor high, and that the opening into the cave at this time was small and probably located close to Rodent Corner.
- ItemThe Taung australopithecine: contextual evidence(Bernard Price Institute for Palaeontological Research, 1980) Butzer, Karl W.None
- ItemThe Makapansgat Limeworks grey breccia: hominids, hyaenas, hystricids or hillwash?(Bernard Price Institute for Palaeontological Research, 1980) Maguire, J. M.; Pemberton, D.; Collett, M. H.The question of the origin of the Makapansgat Limeworks grey breccia is here considered from two viewpoints: (a) the accumulation of bones within a catchment area; and (b) the possible concentration of the bones in their final resting place. The potential role of hyaenas and porcupines as bone-accumulating agents is investigated. Nine categories of hyaena damage to bone surfaces could be distinguished on collections of bone taken from a series of recent hyaena breeding dens. All nine categories can be demonstrated in identical form on fossil bones from the grey breccia. It is concluded that carnivores have played a more substantial role as accumulators of the bones in this breccia than has previously been acknowledged. Porcupines are excluded as major contributors to the grey breccia bone assemblage on the basis of the low percentage of porcupine-gnawed bones present compared with recent porcupine accumulations. Furthermore, the pattern of damage observed on porcupine-collected skeletal elements does not resemble that documented for the grey breccia. A 3-dimensional computer plot of the topography of the Limeworks travertine floor shows the presence of two larger and two smaller basins separated from each other by floor "highs". A floor "high" around the grey breccia is demonstrated and may have been a significant factor in bone concentration. Sedimentation within separate basins need -not necessarily have been synchronous or equivalent, and the practice of equating Members from one part of the cavern to another is questioned. Stereographic projections of the dip and strike orientations of the long axes of a number of in situ grey breccia bones in two separate areas indicate orientation patterns and imbrication. The results of the projections suggest that a combination of water current action and gravity may have been responsible for the present configuration of the bones.
- ItemThe sedimentology of some Transvaal hominid cave deposits and its environmental and chronological implications(Bernard Price Institute for Palaeontological Research, 1980) Partridge, T. C.The sedimentology of cave deposits is principally influenced by two sets of factors: (1) those relating to the morphology of the depository and its evolution through time; and (2) those resulting from external influences, including the production of sediments and their introduction into the cave under varying conditions of climate and vegetation cover. The interaction of these two sets of factors often poses unique sedimentological problems which differ markedly from those encountered in other sedimentary environments. In particular, the imprint of intracavernous conditions on specific sedimentary facies frequently complicates interpretations relative to extracavernous environmental influences. Inferences from sedimentological studies should, therefore, be supplemented as far as possible with other evidence - for example from isotope analyses, palynology and faunal studies - in any meaningful attempt to reconstruct ancient environments from these deposits. The sequence of intracavernous events which occurred during the accumulation of the Makapansgat and Sterkfontein Formations will be outlined in relation to the probable imprint of external changes. When viewed in conjunction with the evidence of variations in the concentrations of 13C and 18O in the various stratigraphic units and with interpretations relative to the extent of the cover of woody vegetation near each site, a fairly consistent picture of climate fluctuations emerges. These early fluctuations may, in a general way, parallel those recorded by Shackleton and Opdyke in the northern hemisphere for the period between 3,2 My B.P. and the beginning of the Quaternary.
- ItemPalaeontologia africana Volume 23(Bernard Price Institute for Palaeontological Research, 1980)
- ItemDating possibilities for the South African hominid sites(Bernard Price Institute for Palaeontological Research, 1980) Vogel, J. C.A brief description is given of dating methods which may in future prove to be applicable to the calcified ossiferous cave deposits of the early hominid sites in the Transvaal. Potentially the techniques based on amino acid racemisation, uranium series disequilibrium and radiation damage could provide dates for at least the upper members of the cave formations. The results would, however, have. to be calibrated in the younger time-range by radiocarbon dating of parallel samples.
- ItemSome problems in using landforms as evidence for climatic change(Bernard Price Institute for Palaeontological Research, 1980) Marker, M. E.Landforms are used as evidence for past climatic conditions on the basis of morphoclimatic explanation. Problems arise because the relationships from climatic parameters through process to landforms are not direct. The problems inherent in employing landform evidence are discussed under the headings: Recognition, Interpretation, Application, Correlation and Chronology. It is concluded that certain landforms provide unequivocal evidence for climatic change even though landform evidence must always be circumstantial. An individual landform alone does not prove climatic change although an entire assemblage exhibiting similar tendencies might. Where, however, evidence from other areas and other lines of evidence also point to the same conditions, then the conclusions may be accepted more securely. Landform evidence has a place in Quaternary studies, but it must be used with caution.
- ItemThe Sterkfontein Valley australopithecine succession(Bernard Price Institute for Palaeontological Research, 1980) Vrba, E. S.If we knew the kinds and relative frequencies of animal species belonging to a natural living community, we would be able to predict the supporting environment with some accuracy. Unfortunately for the palaeoecologist the equivalent parameters of a fossil assemblage usually differ substantially from those of the ancient living parent community. This distortion results from the action of a number of taphonomic factors during the passage of remains "from the biosphere to the lithosphere". The major steps of palaeoenvironmental reconstruction from fossils follow a circuitous route of erecting hypotheses upon hypotheses: 1. Analyses of taxonomy and relative frequency. 2. Recognition of environmental indicators (El): Which fossil groups are environmentally specialized (i.e. good Els); and precisely what kind of environments do they indicate? (estimated from modern analogy). 3. Recognition of taphonomic biases: Have the proportions of Els in the original community been distorted by preferential inclusion and survival in the assemblage? Such bias or distortion may be caused by many factors, for example seasonality and duration of deposition, geographic area sampled, mode of death, transport and accumulation, species death rate, and so forth. 4. Estimation of El proportions in the original community by correcting where necessary for taphonomic biases. 5. Interpretation of taxonomic and morphologic change: Let us assume that estimates of original EI proportions, resulting from steps 1-4, can be seen to change significantly in chronologically successive strata in one area like the Sterkfontein Valley. Must such morphologic/ taxonomic change necessarily imply a change in the ecosystem, or may it imply no more than the passage of time? A particular palaeoenvironmental study on fossil assemblages from Sterkfontein, Swartkrans and Kromdraai is followed through steps 1-5 to its conclusion.
- ItemOn the age of Border Cave hominids(Bernard Price Institute for Palaeontological Research, 1980) Beaumont, Peter B.Cited evidence suggests that Border Cave hominids 1-3 and 5 are associated with MSA phases 1-2 and date back to c. 90 000-110 000 yr B.P. These remains are fully modern in terms of morphology, and incipient Khoisan features are seemingly present in the case of BC1. This evidence is taken to mean that truly ancestral forms of our own species probably range back into the late Middle Pleistocene of sub-Saharan Africa. Such a scenario implies that previous phologenetic reconstructions have been based on only the final quarter or so of modern man's evolutionary history.
- ItemThe potential vegetable dietary of Plio-Pleistocene Hominids at Makapansgat(Bernard Price Institute for Palaeontological Research, 1980) Maguire, BrianNeither fossil pollens nor macroscopic plant remains have as yet been reported from the Makapansgat Limeworks breccias; hence there exists no direct means of assessing the character of the local floral environment during australopithecine times. However, it is suggested that provided acceptable evidence on the nature of the contemporaneous climate and particularly rainfall can be obtained, by indirect means a comparatively full picture may be presented, both of the local vegetation and of the plant foods available to hominids in the area at that time. The methods and types of data employed in deducing the nature of the palaeoflora at Makapansgat, under hypothetical conditions of rainfall both higher and lower than the present, are briefly summarised. The extant vegetation in the Makapansgat area is briefly described and the food plant component is discussed with reference to the numbers and types of food plant present, the numbers and types of foods these plants provide and the times at which they are availabe. These data relate to two study areas, one lying within an 8 km radius of the Limeworks site, the other lying within a 16 km radius. The present climate and floral-climatic relationships at Makapansgat in recent and historic times are discussed. The nature of secondary disturbance in the area is discussed and its effects emphasised. The conjectured nature and food plant component of the prehistoric Makapansgat vegetation is discussed in relation to hypothetical conditions of both increased and diminished rainfall. The five vegetation types represented at Makapansgat provide a total of 117 food plants within a radius of 8 km of the Limeworks site, and 150 within a 16 km radius. These plants are mainly trees and shrubs providing edible fruits.