Volume 30 1993

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7th Biennial Conference of the Palaeontological Society of South Africa 6th-9th September 1992 Programme
(Bernard Price Institute for Palaeontological Research, 1993)
A detailed description of the internal structure of the skull of Emydops (Therapsida: Dicynodontia)
(Bernard Price Institute for Palaeontological Research, 1993) Fourie, Heidi
A detailed morphological study of two skulls of Emydops was undertaken by using the serial grinding technique. Graphic reconstructions of various aspects of the skulls were made. The internal structures are described in detail and compared to other small dicynodonts such as Eodicynodon, Pristerodon, Cistecephalus and Diictodon. Emydops and Cistecephalus show more advanced features in common with each other than with other dicynodonts. The structure of the skull of Emydops conforms within the limits of variation known for this genus, to descriptions given in the literature. It was found that Emydops differs from other dicynodonts in that the parasphenoid has a definite suture with the pterygoid anterior to the pterygoid-basisphenoid suture, instead of passing between the pterygoids without contacting them, as reported by Olson (1944).
Dicynodont (Therapsida) bone histology: phylogenetic and physiological implications
(Bernard Price Institute for Palaeontological Research, 1993) Chinsamy, Anusuya; Rubidge, Bruce S
The bone histology of humeri of a number of taxonomically well established and easily definable dicynodont genera is described and compared. The bone of Aulacephalodon, Cistecephalus, Dicynodon, Endothiodon, Lystrosaurus, Kannemeyeria and Oudenodon consists of alternating fibro-lamellar and lamellated bone tissue, while that of Diictodon consists only of fibro-lamellar tissue. The presence of fibro-lamellar bone in all the genera studied, indicates that the bone was deposited rapidly, but the occurrence of lamellated bone tissue suggests that all the genera except Diictodon, also had intermittent periods of slow growth. This is the first time that a comparative study of bone histology of different dicynodont genera has been attempted by using one particular bone element to standardise intergeneric comparisons.
Fossil proboscidean remains from Bolt's Farm and other Transvaal cave breccias
(Bernard Price Institute for Palaeontological Research, 1993) Cooke, H B S
Proboscidean remains are very rare in the Transvaal cave breccias and the few specimens recovered are generally fragmentary but deserve description because of their potential value in correlation and dating. The best specimen is the back half of a left lower molar from Pit 7 of the University of California African Expedition's work at Bolt's Farm. It was regarded by Maglio as representing Elephas ekorensis but closer examination suggests that there are some more progressive characters and it most likely represents Elephas recki brumpti. The stump of a second molar from Bolt's farm also accords with this taxon. Makapansgat has furnished 14 fragmentary fossils, 6 of them tusk or root remains. Particularly interesting is the occurrence of a pair of cones from a molar of Anancus. The scrappy elephantid material from Makapansgat may be referred tentatively to an early stage of the Elephas recki lineage, as also a mandible fragment from Sterkfontein with the two anterior milk teeth. An anterior milk tooth from Swartkrans Member 3 exhibits broader and higher lamellae than in E. recki and most probably belongs to the more advanced E. iolensis to which most of the Vaal River elephants have been referred.
Fossil wood from the Brandvlei area, Bushmanland as an indication of palaeoenvironmental changes during the Cainozoic
(Bernard Price Institute for Palaeontological Research, 1993) de Wit, Michiel C J; Bamford, Marion K
Remnants of Cainozoic fluvial deposits occur along the northerly flowing Sak River in Bushmanland, between Brandvlei and Sak River Station. The terraces can be subdivided into older and younger deposits, and occur approximately 60m and between 20m and 30m above the present-day river respectively. The older deposits are found to the east of the Sak River in the Geelvloer palaeo-valley. Most of the older 'terraces' are either hill-slope deposits or fans, and represent reworked fluvial sediments. A rounded vertebrate bone and several pieces of sub-rounded fossil wood were found in these deposits, which indicate a mid Miocene age for the original older deposits. Some of the fossil-wood samples have been positively identified as extant angiospermous families. The occurrence of fagaceous wood in two samples is of great interest biogeographically. Both the vertebrate fossil and the wood suggest that the mid Miocene climate was subtropical. At the end of the Miocene the wet period changed to arid conditions, and mature calcretes developed. This dry period was interrupted by pluvials during which the younger gravels were deposited. These alluvial terraces are interpreted as an aggradational sequence of braid bars associated with a wandering river, deposited under semi-arid conditions. Two well-rounded fossil-wood clasts, presumably reworked from the older terraces, were found in these sediments. One of which is identified as Polygalaceae. Based on similarities of lithofacies and style of diagenesis with the Van Wyksvlei sequence to the east, the younger terraces are probably Plio-Pleistocene in age.
Glimpses from Gondolin: a faunal analysis of a fossil site near Broederstroom, Transvaal, South Africa
(Bernard Price Institute for Palaeontological Research, 1993) Watson, V
The faunal analysis of a Plio-pleistocene site near Broederstroom, 34km north west of Pretoria, in the Transvaal has revealed a fossil fauna possibly as old as 2 million years. A single Homo sapiens tooth probably more recent than the rest of the deposit was recovered. Twenty seven mammal taxa were recovered with Redunca arundinum, the reedbuck, being the most common and the fossil klipspringer Oreotragus major the next most common. A large metridiochaerine suid was well represented. Primate remains were remarkable by their absence. From damage to the bones the most likely collecting agent was leopard. The fauna suggests a hilly grassy environment with permanent water and rocky outcrops. Open grass plains must have been in relatively close vicinity of the dolomite cave.
Palaeontologia africana Volume 30
(Bernard Price Institute for Palaeontological Research, 1993)
Palaeontology and the National Monuments Council
(Bernard Price Institute for Palaeontological Research, 1993) Deacon, Janette
The National Monuments Council is the only statutory body that actively protects the palaeontological resources in South Africa. It does this in three ways: by issuing permits for excavation, collection and export of palaeontological material; by declaring sites of particular scientific importance national monuments; and by compiling a register of conservation-worthy property that can include palaeontological sites. It is important that palaeontologists in South Africa are aware of the terms of the National Monuments Act and that they assist the National Monuments Council in drawing up policy and guidelines. Close co-operation between the PSSA and the NMC can be of mutual benefit with regard to formulating principles and criteria for evaluating permit applications, identifying sites that may be affected by development, and predicting the implications that promoting palaeontology may have for site protection and management.
Postcranial evidence for the evolution of the Black Wildebeest, Connochaetes gnou: an exploratory study
(Bernard Price Institute for Palaeontological Research, 1993) Brink, James S
Black wildebeest fossils from the interior of South Africa and the Cape coastal zone are compared to modern specimens in order to trace the pattern of morphological change and the distribution of the species through time. Measurements taken on selected postcranial skeletal elements, i.e. the axis and metapodials, suggest that the evolution of the black wildebeest was marked by a general reduction in body size. It appears that the evolution of Connochaetes gnou from a blue wildebeest-like (C. taurinus) ancestor is best documented in areas to the south of the Vaal River. Although the geographic range of the two temporal subspecies of C. gnou (C. gnou laticornutus and C. gnou antiquus) included the Cape ecozone, the reduction in body size appears to have beeen accelerated in the Cape coastal zone where in the Last Glacial sensu lato there was a regionally distinct population. This population, of smaller body size than extant populations, became extinct at the end of the Last Glacial with the onset of higher sea levels.
A preliminary estimate of the age of the Gladysvale australopithecine site
(Bernard Price Institute for Palaeontological Research, 1993) Berger, Lee R
Excavations conducted at the Gladysvale site in the Transvaal, South Africa during 1991 -1992 have revealed an abundant Plio-Pleistocene fossil fauna from the limeworks breccia dumps and in situ decalcified deposits. To date, over 600 specifically identifiable macro-mammalian specimens have been recovered including the remains of Australopithecus. These identifications have revealed that the Gladysvale site has an extremely diverse macro-mammalian faunal assemblage equal to many other South African Plio-Pleistocene fossil sites. Comparison of the Gladysvale macromammalian fauna with those of the other early hominid-associated sites in South Africa indicates an age for the deposit(s) at Gladysvale between 1.7- 2.5 m.a.. ln addition, the Kromdraai A macromammalian assemblage is considered to be closer in age to the Gladysvale assemblage than any other South African faunal assemblage.
Sensitivity of xylem vessel size and frequency to rainfall and temperature: implications for palaeontology
(Bernard Price Institute for Palaeontological Research, 1993) February, Ed
Based on the xylem vessel size and frequency in fossil wood, a number of studies have developed theories on climate change through time. The basic premise of these studies is that xylem vessel size decreases while vessel frequency increases with intensifying aridity. In this paper the relationship between rainfall and xylem vessel size and frequency is examined in two extant tree species. The results indicate that rainfall is related positively to vessel diameter and negatively to vessel frequency in Combretum apiculatum and Protea caffra. Xylem vessel size of both species is between 50 and 100 µm. However, the two species exhibit different responses to rainfall in that P. caffra has much smaller diameter vessels than C. apiculatum in high rainfall areas. These differences indicate that the potential for using xylem anatomy as a palaeoclimatic indicator has not been fully utilised. A more precise picture of climate change through time is possible with a more refined statistical analysis of reliably identified fossil wood.
Statistical analysis of skulls of Triassic proterosuchids (Reptilia, Archosauromorpha) from South Africa
(Bernard Price Institute for Palaeontological Research, 1993) Welman, Johann; Fleming, Alex
Size-related differences have previously been considered to be important in distinguishing the four proterosuchian archosauromorph species described from South Africa. Previous authors hypothesized that these differences were due to allometric growth. In this study, a statistical analysis of 85 parameters measured in 12 skulls, including all the type specimens, has been carried out. The results show that all the specimens can be fitted into a growth series, supporting a hypothesis expressed by Cruickshank (1972). Variation in the growth rate of parts of the proterosuchid skull and the possible functional significance of such allometric growth patterns are investigated. On the basis of specimens measured in this study and assuming that they all belong to a single species, it would appear that the South African proterosuchids did not display a strong degree of sexual dimorphism.
Taxonomic and evolutionary affinities of Papio izodi fossils from Taung and Sterkfontein
(Bernard Price Institute for Palaeontological Research, 1993) McKee, Jeffrey K
Papio izodi is an extinct papionin found at Taung and Sterkfontein. The taxonomic status of southern African fossils sometimes referred to P. izodi is clarified here in order to verify the existence of the species at Sterkfontein and define the morphological characteristics distinguishing it from P. angusticeps, a later species of similar size. P. izodi may be the earliest known species of the genus Papio in southern Africa, as the putative contemporary presence of the derived species Papio hamadryas robinsoni cannot be confirmed at Sterkfontein. P. izodi retains some of the primitive features found in Parapapio broomi, suggesting a close evolutionary link between the two species.
Taxonomic description of fossil wood from Cainozoic Sak River terraces, near Brandvlei, Bushmanland, South Africa
(Bernard Price Institute for Palaeontological Research, 1993) Bamford, Marion K; de Wit, Michiel C J
Seven pieces of silicified wood are described from two sites near the Sak River, Bushmanland. The Miocene deposit yielded five specimens which can be assigned to the Dipterocarpaceae, Fagaceae, Myrtaceae, Oleaceae and Rutaceae. Of the two logs recovered from the Plio-Pleistocene deposit, only one was well enough preserved to be assigned to the Polygalaceae. All the woods indicate that the palaeoenvironment in that region was tropical to subtropical based on the wood structure, growth rings and from their modem counterparts.
Undescribed suid remains from Bolt's Farm and other Transvaal cave deposits
(Bernard Price Institute for Palaeontological Research, 1993) Cooke, H B S
Although individual suid specimens from other sites have been described, only Makapansgat has been treated comprehensively, but much new material has come to light in the past three decades. The University of California African Expedition worked several sites of different ages at Bolt's Farm and the material recovered includes a virtually complete, slightly compressed, skull of Phacochoerus modestus (= P. antiquus Broom 1948) from Pit 3, associated with Antidorcas recki, and also several cranial and dental fragments from Pit 14 that belong to the typical Makapansgat Potamochoeroides shawi. Bolt's Farm was the source of a cranial specimen described by Broom as "Notochoerus meadowsi" (= Metridiochoerus andrewsi); other specimens referred to this taxon and described by Shaw as from "Sterkfontein Lime Works" more probably came from Bolt's Farm as well. Broom's cranium and a pair of mandibles have closer resemblances to Metridiochoerus jacksoni of East Africa. Swartkrans has yielded both described and undescribed material referred to Phacochoerus modestus and to Metridiochoerus. Discounting Shaw's material, only one small specimen has come from the Sterkfontein Type Site, a mandible fragment of a juvenile with an incompletely formed third molar in alveolus but it can be matched remarkably closely with a specimen from Makapansgat and there is very little doubt that it belongs to Potamochoeroides shawi. An undescribed third molar from the pink breccia at Makapansgat is comparable with early Notochoerus scotti from East Africa. The status of Notochoerus capensis is reconsidered.
Variability in shape of the dental arcade of Homo sapiens in Late Pleistocene and modern samples from southern Africa
(Bernard Price Institute for Palaeontological Research, 1993) Thackeray, J Francis; Kieser, J A
Mandibles are among the most common skeletal elements of Late Pleistocene specimens of Homo sapiens from southern African sites (notably Klasies River Mouth and Border Cave). For this reason mandibles have been selected for study to compare with samples drawn from modem populations (including South African negroes, Khoisanoid "Bushmen" and caucasoids). An analysis of shape of the dental arcade, based on the spatial distribution of molars, premolars and canines, indicates that several of the Late Pleistocene samples (including KRM 41815) are outside the range of variation found in modem African and caucasoid populations, and in this respect, cannot be described as "anatomically modem", sensu strictu. There appears to be a trend in the process of modernisation, from very flared dental arcades (notably in the case of the Kabwe skull, representing "archaic" H. sapiens), through moderately flared arcades (as found in Late Pleistocene "nearly modem" samples) towards a less flared condition which is found in modern Africans and caucasoids.

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