Volume 23 1980

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Last integral shorelines in the South Cape
(Bernard Price Institute for Palaeontological Research, 1980) Davies, Oliver
My 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
The 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.
Dune 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.
Late Pleistocene and Holocene climates as viewed from Verlore Vlei
(Bernard Price Institute for Palaeontological Research, 1980) Parkington, John
Evidence from a number of sites along the lower reaches of the Verlore Vlei and the adjacent coastline is interpreted as reflecting considerable environmental change since about 18 000 B.P. In particular seven points are relevant.
Swartkrans 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.
On the genesis of bipedalism
(Bernard Price Institute for Palaeontological Research, 1980) Suzman, Ivan M.
Bipedalism is the hallmark of the Hominidae, past and present. Only against this fundamental adaptive background could cerebral, dental and manual modifications develop to change ape into ape-man, and ape-man into man. Yet surprisingly little is known of its origin, of the variety of forms of locomotor behaviour it has encompassed, or about the sequence of postural refinements which has led to our modern pattern of stance and gait. In an attempt to trace the Plio-Pleistocene history of two-footedness, lower limb fossils of early hominids are examined here. South and East African sites are covered, with special reference to the period 3,6 to 1 ,5 My ago. Numerous structural challenges had to be met so that uprightness could evolve successfully. Several are considered of special interest here, including sacroiliac joint consolidation, a lumbo-acetabular weight transfer mechanism, acetabular remodelling and femorotibial alignment. These features have contributed to the attainment of balance over two limbs, minimal eccentric joint movements and a flow of body weight close to or through joint centres. A primary palaeoanthropological question is then discussed: the time period during which cladogenesis brought about the emergence of earliest Homo from an Australopithecus stock. Lower limb evidence is used to evaluate whether A. africanus postdated this split, and in so doing the possibility is considered that southern African australopithecines exhibited parallel evolution to Homo, rather than having been ancestral. Finally, comparisons are drawn between certain East and South African features of pelvic and lower limb evolution. A chronology of osseous aspects of such evolution is proposed.
An 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.
"Australopithecus afarensis" and A. Africanus: Critique and an alternative hypothesis
(Bernard Price Institute for Palaeontological Research, 1980) Tobias, Phillip V.
During the seventies, a succession of East African discoveries has been claimed to represent the "true" ancestral line of modern man, thus relegating A. africanus, and especially its Transvaal subspecies, to a subordinate role in hominid phylogeny. The latest such attempt has been the claim of Johanson and his co-workers that the 3, 7-2,6 My-old hominids of Laetoli in Tanzania and of Hadar in Ethiopia represent a new species, "A. afarensis", which led to H. habilis, whilst A. africanus represents early stages in a specialized side-branch leading to A. robustus and A. boisei. A critique of the diagnostic criteria of "A. afarensis" reveals that on the available evidence, the Laetoli and Hadar fossils cannot be distinguished at specific level from A. africanus transvaalensis. Furthermore, it is by no means clear that the pooling for statistical and comparative purposes of the Hadar and Laetoli fossils is justified. Hominids from the two sites are separated by about 800 000 years and about 1 600 km as well as by morphometric differences. As an alternative hypothesis, it is proposed that the Laetoli and Hadar hominids belong to the same lineage as that represented by the hominids of Makapansgat Members 3 and 4 and of Sterkfontein Member 4. Moreover, it is hypothesized that the Laetoli and Hadar hominids cannot be separated morphologically from A. africanus and that they represent two new subspecies of that species. Since "A. afarensis" is tied to a Laetoli specimen as holotype, only the Laetoli specimens should be designated A. africanus afarensis (though A. africanus tanzaniensis suggested by the author in 1978 would have been a more appropriate nomen) and the Hadar fossils A. africanus aethiopicus. These newest East African discoveries afford strong confirmation of the hypothesis that A. africanus is the common ancestor of the two later hominid lineages, A. robustuslboisei and Homo, leading from H. habilis through H. erectus to H. sapiens.
Palaeontologia africana Volume 23
(Bernard Price Institute for Palaeontological Research, 1980)
The 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.
On 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.
Models 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.
Some 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.
Further observations on the nature and provenance of the lithic artefacts from the Makapansgat Limeworks
(Bernard Price Institute for Palaeontological Research, 1980) Maguire, Brian
A selected sample of 45 lithic specimens from the Makapansgat Limeworks site, considered to be artefacts showing acceptable evidence of having been deliberately flaked or utilized, are illustrated, described and discussed. The sample comprises a single stalactite fragment from the grey breccia (Member 3), 2 chert pieces from the pink breccia (Member 4), 24 chert and dolomite pieces and 7 of quartzite from the Phase II breccia (Member 5) , 2 pieces- one of quartzite and one of vein quartz- of doubtful provenance, and 9 chert pieces from the overburden. Recognition of deliberate flaking of the native rocks (dolomite and chert) is often difficult because of the feebly conchoidal fracture often produced, and the susceptibility of the dolomite to weathering. Experimentally produced fracturing in chert demonstrates that such artificial fractures differ clearly from those produced by the normal break-up of this rock. The repeated appearance of two crude tool forms is discussed. The method adopted here in the analysis of the small-scale damage on working edges of suspected artefacts is considered to demonstrate independently their authenticity or otherwise. This procedure, whereby eight perceptible attributes are differentiated and evaluated, should prove useful in augmenting other criteria employed in the examination of all primitive materials suspected to be cultural. The Limeworks artefacts are also broadly discussed with reference to the Limeworks stratigraphy as originally described by Brain (1958) and as recently proposed by Partridge (1979) . The derivation of suspected artefacts in the overburden and in Member 5 are discussed. It is concluded that the great majority of those in the overburden were derived by decalcification of the underlying breccias, while those in the pebble bands of Member 5 appear to be primarily of intracavernous origin.
The 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.
Carnivore 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.
The 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.
Dating 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.
The Taung australopithecine: contextual evidence
(Bernard Price Institute for Palaeontological Research, 1980) Butzer, Karl W.
None
Tertiary 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.