. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 76 ANNALS OF THE SOUTH AFRICAN MUSEUM lands to be increasingly confined to the immediate vicinity of the river, thus restricting the habitat available to browsing species. Such animals would then have been increasingly hard-pressed in exploiting the diminishing food resour- ces, with an increase in mortality caused by starvation being likely. In addition, it is possible that as the rainfall pattern was changing from a summer to winter maximum, it became more irregular and perhaps even diminished. Dro
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 76 ANNALS OF THE SOUTH AFRICAN MUSEUM lands to be increasingly confined to the immediate vicinity of the river, thus restricting the habitat available to browsing species. Such animals would then have been increasingly hard-pressed in exploiting the diminishing food resour- ces, with an increase in mortality caused by starvation being likely. In addition, it is possible that as the rainfall pattern was changing from a summer to winter maximum, it became more irregular and perhaps even diminished. Droughts might, therefore, have been an added hardship confronting the fauna. There is evidence that at least some of the 'E1 Quarry browsers were ill-adapted to prevailing conditions by bed 3aN times. For example, teeth of Sivatherium from this level sometimes exhibit hypoplasia of the enamel (fig. 15). B no ll|l!ll!ll!|ll!l!l!l|llllllll|l Fig. 15. A-C. Incisors of Sivatherium hendeyi from the PPM 3aN (unnumbered Dump 10 specimens), with hypoplasia of the enamel. D. A healthy specimen. This condition results from disturbances in the formation of the enamel matrix during development of the teeth, and is a positive indication of ill-health in the immature individual (Scott & Symons 1974). The aetiology in the case of the bed 3aN Sivatherium is not known, but a nutritional inadequacy is most likely. Such inadequacies could be caused by reduced food resources. A second dental abnormality observed amongst bed 3aN browsers, is irregular and excessive wear of teeth. Although this was observed in several of the bovid species, it is most common in the teeth of the reduncines and/or tragelaphines. There are problems in distinguishing the teeth of these animals (see below), but it is virtually certain that the abnormal bed 3aN specimens belong to the reduncines (mostly Kobus subdolus, but some Kobus sp. B), the. Please note that these images are extracted from scanned page images that m
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
