An analysis of crania from Tell-Duweir using multiple discriminant functions

Historical and archaelogical evidence suggests that the Iron Age biblical city of Lachish had a multinational population of diverse geographical origins. A multivariate analysis of crania, using canonical discriminant functions and metric variables, tends to confirm this. The approach employed stresses that population discriminant analysis studies should be both biologically and statistically legitimate. An ecological interpretation of the data suggests a research design for analyzing the affinities of cranial series. Similarities probably should be assessed in an analytical space containing the widest possible range of variation.     

The application of multiple discriminant analysis to the reconstruction of the vegetation history of Fynbos,southern Africa

The fynbos biome of southern Africa is floristically diverse and explanations of this diversity have frequently invoked historical processes, in particular environmental change. Few sites exist within the region which facilitate palaeoecological reconstructions, but a relatively deep sequence of organic sediments in the Cederberg mountains in the south-western Cape Province of South Africa has been analysed for fossil pollen content. Conventional zonation of the resultant absolute pollen diagram reveals an apparent absence of marked vegetation change during the last 14500 years. Pollen analysis has its limitations under circumstances where the high plant diversity and incompleteness of reference material entails that pollen identifications may usually be made only down to family level. In order to assess whether the presumed stability of vegetation communities during the late Pleistocene and Holocene is an artefact of these taxonomic limitations, a comprehensive contemporary pollen sampling programme was conducted. Multiple discriminant analysis was applied to the contemporary data and suggests that contemporary pollen spectra are accurate reflections of the surrounding vegetation. Discriminant analysis is further able to identify analogue communities prevailing at various times during the sedimentation period. Rather than being truly stable, the vegetation of these mountains is shown to have been dynamic in response to changes in precipitation inputs, fire regime and human activity. Nevertheless, the vegetation history is characterised by relatively subtle changes in plant community patterns, a fact which may have played an important role in the evolution of prolific species diversity. It is concluded that contemporary pollen rain studies, combined with multiple discriminant analysis, may be especially valuable interpretive tools in situations of high plant species richness.     

Dynamic Locomotor Capabilities Revealed by Early Dinosaur Trackmakers from Southern Africa

Background

A new investigation of the sedimentology and ichnology of the Early Jurassic Moyeni tracksite in Lesotho, southern Africa has yielded new insights into the behavior and locomotor dynamics of early dinosaurs.

Methodology/Principal Findings

The tracksite is an ancient point bar preserving a heterogeneous substrate of varied consistency and inclination that includes a ripple-marked riverbed, a bar slope, and a stable algal-matted bar top surface. Several basal ornithischian dinosaurs and a single theropod dinosaur crossed its surface within days or perhaps weeks of one another, but responded to substrate heterogeneity differently. Whereas the theropod trackmaker accommodated sloping and slippery surfaces by gripping the substrate with its pedal claws, the basal ornithischian trackmakers adjusted to the terrain by changing between quadrupedal and bipedal stance, wide and narrow gauge limb support (abduction range = 31°), and plantigrade and digitigrade foot posture.

Conclusions/Significance

The locomotor adjustments coincide with changes in substrate consistency along the trackway and appear to reflect ‘real time’ responses to a complex terrain. It is proposed that these responses foreshadow important locomotor transformations characterizing the later evolution of the two main dinosaur lineages. Ornithischians, which shifted from bipedal to quadrupedal posture at least three times in their evolutionary history, are shown to have been capable of adopting both postures early in their evolutionary history. The substrate-gripping behavior demonstrated by the early theropod, in turn, is consistent with the hypothesized function of pedal claws in bird ancestors.     

Estimation of age from the pubic symphysis by means of multiple regression analysis.

This study has been carried out to assess the age from the pubic symphysial surface employing a multiple regression analysis and a quantification theory model I analysis. Using partial regression coefficients and/or normalized scores obtained from the analyses, ages of skeletal remains can be quantitatively estimated with a fairly high reliability. The use of this method is, however, limited to the samples between 18 and 38 years of age, because age changes in the symphysial surface show large variations after about 40 years. The reliability of this method was also examined.     

Comparative analysis on the genetic relatedness of Sorghum bicolor accessions from Southern Africa by RAPDs,AFLPs and SSRs

In order to get an overview on the genetic relatedness of sorghum (Sorghum bicolor) landraces and cultivars grown in low-input conditions of small-scale farming systems, 46 sorghum accessions derived from Southern Africa were evaluated on the basis of amplified fragment length polymorphism (AFLPs), random amplified polymorphic DNAs (RAPDs) and simple sequence repeats (SSRs). By this approach all sorghum accessions were uniquely fingerprinted by all marker systems. Mean genetic similarity was estimated at 0.88 based on RAPDs, 0.85 using AFLPs and 0.31 based on SSRs. In addition to this, genetic distance based on SSR data was estimated at 57 according to a stepwise mutation model (Deltamu-SSR). All UPGMA-clusters showed a good fit to the similarity estimates (AFLPs: r = 0.92; RAPDs: r = 0.88; SSRs: r = 0.87; Deltamu-SSRs: r = 0.85). By UPGMA-clustering two main clusters were built on all marker systems comprising landraces on the one hand and newly developed varieties on the other hand. Further sub-groupings were not unequivocal. Genetic diversity (H, DI) was estimated on a similar level within landraces and breeding varieties. Comparing the three approaches to each other, RAPD and AFLP similarity indices were highly correlated (r = 0.81), while the Spearman's rank correlation coefficient between SSRs and AFLPs was r = 0.57 and r = 0.51 between RAPDs and SSRs. Applying a stepwise mutation model on the SSR data resulted in an intermediate correlation coefficient between Deltamu-SSRs and AFLPs (r = 0.66) and RAPDs ( r = 0.67), respectively, while SSRs and Deltamu-SSRs showed a lower correlation coefficient (r = 0.52). The highest bootstrap probabilities were found using AFLPs (56% on average) while SSR, Deltamu-SSR and RAPD-based similarity estimates had low mean bootstrap probabilities (24%, 27%, 30%, respectively). The coefficient of variation (CV) of the estimated genetic similarity decreased with an increasing number of bands and was lowest using AFLPs.     

Climatic conditions in Southern Africa since the last glacial maximum, inferred from pollen analysis

A review of Late Quaternary palaeoclimatic data derived from several pollen sequences, between ca. 22 and 34°S in Southern Africa, shows a degree of similarity in temperature and moisture variations between the various site. Pollen data from sites such as Wonderkrater and Rietvlei (Transvaal), Tate Vondo (Venda), Elim (Orange Free State), Equus Cave (Southern Kalahari) and Boomplaas (Cape Province) suggest relative dryness during the Last Glacial Maximum, wet conditions during the Late Glacial, and dry conditions during the Early Holocene ca. 8000 yr B.P., followed by progressively moister conditions peaking soon after the development of a temperature optimum ca. 6500 yr. B.P. Problems with radiocarbon dating of polleniferous spring deposits, however, prevent precise correlations of especially Late Pleistocene sequences. Different seasonal patterns in the Late Glacial and Early Holocene may explain palaeobotanical data and are partly compatible with simulations of past climates of Kutzbach and Guetter (1986).     

Pollen analysis of Iron Age cow dung in southern Africa

Thick accumulations of consolidated cow dung occur in ancientkraals (byres or corrals) in the bushveld and highveld areas of Zimbabwe, Botswana, and South Africa dating from the last 2000 years. They originated from long-term cattle herding by Iron Age people. The vitrified or baked dung deposits are thought to be a product of the burning of cow dung as fuel, either for domestic purposes or for iron smelting. In order to establish the palaeoecological potential of this material, 36 samples of cow dung from archaeological sites within the present-day savanna and grassland biomes were analyzed for pollen and other microfossils. Of the samples, 29 contained pollen together with other microfossils that support a faecal origin of the material such as sordariaceous ascospores,Thecaphora, Gelasinospora, andChaetomium, and eggs of the intestinal parasiteTrichuris. Similar microfossils were also found in recent fresh cow dung from the same study areas. The presence of pollen grains and spores in most of the Iron Age samples lead to the assumption that they survived the burning because fire temperatures were not high enough to destroy them. Pollen in these cow dung pieces is apparently sealed and can be preserved under open-air conditions at sites under which pollen in other deposits like soils, will decay away. Good pollen preservation and palynomorph diversity were found with mainly Poaceae, and secondly Chenopodiaceae and Cyperaceae as the most important pollen types, while trees and shrubs indicating savanna are rare. In the case of the samples that came from the subtropical savanna biome the latter result is unexpected and suggests that the cattle were kept in more open vegetation than the woody environments of today. Recent cow dung samples reflect the composition of present-day vegetation by showing considerably higher proportions of tree pollen than the fossil assemblages.     

Prediction of protein structural class by discriminant analysis

Protein structural class--alpha, beta, mixed (alpha/beta or alpha + beta), irregular--can be predicted from the amino acid sequence by discriminant analysis. Discrimination is based on distributions, in the classes, of vectors of attributes characterizing the sequences. In this paper, two sets of attributes and two methods of estimating their distributions are compared using more than 100 proteins from the Protein Data Bank. The best results were obtained when canonical variates of the frequencies of occurrence of 20 amino acids and non-parametric estimates of their distributions were used. Three variates are sufficient to allocate proteins to one of four classes with 83% reliability (estimated by cross-validation) and four variates allowed allocation to one of five classes with 78% reliability.     

Further studies of crania from ancient northern Africa: an analysis of crania from first dynasty Egyptian tombs, using discriminant functions.

An analysis of First Dynasty crania from Abydos was undertaken using multiple discriminant functions. The results demonstrate greater affinity with Upper Nile Valley patterns, but also suggest change from earlier craniometric trends. Gene flow and movement of northern officials to the important southern city may explain the findings.     

Correlation between soil characters and forest types: a study in multiple discriminant analysis

Multiple discriminant analysis is a useful multivariate technique in vegetation studies that can be employed for several purposes, even if the underlying statistical assumptions are not satisfied. An example of application of this method is discussed: multiple discriminant analysis was successfully used for evaluating the predictivity of forest types defined by numerical classification of vegetation data with respect to soil variables.Species nomenclature follows Pignatti (1982) for vascular plants and Augier (1966) for mosses.The research has been supported by the IDROSER (Bologna, Italy) and by the Italian C. N. R. (Grant no. 83.02548.04, resp. Prof. A. Pirola). We wish to thank Prof. E. Feoli, Prof. E. van der Maarel, Prof. L. Orlóci and Prof. A. Pirola for suggestions. We are also indebted to Dr N. Filippi who analyzed the soil samples.     

Sex determination of Finnish crania by discriminant function analysis

Using multivariant discriminant function analysis, the sex of 232 Finnish crania of known sex was determined. Eight measurements were used to form two discriminant functions. In 80% of cases the sex determination by means of the discriminant functions was identical with the original information. The applicability of the sex discriminant function of Giles and Elliot ('63) for American white and Negro crania was also tested on the Finnish crania. An accuracy of only 65% was attained.     

Moniliformin production and toxicity of different Fusarium species from Southern Africa.

Four new moniliformin-producing species of Fusarium were found, viz., F. acuminatum, F. concolor, F. equiseti, and F. semitectum. Isolates of F. acuminatum and F. concolor produced large amounts of moniliformin (3.4 and 9.5 g/kg, respectively), whereas isolates of the other three species yielded less than 30 mg/kg. The production of moniliformin by isolates of F. oxysporum and F. avenaceum from southern Africa is described. All 14 toxic isolates of F. oxysporum produced moniliformin. Most isolates of F. fusarioides and all six isolates of Fusarium moniliforme va. subglutinans tested produced moniliformin, as did 28 of 36 toxic isolates of F. moniliforme. A number of F. moniliforme isolates produced greater than 10 g/kg, and one isolate yielded 33.7 g/kg in corn after incubation for 5 weeks at 25 degrees C. Moniliformin production in the field in corn ears was shown by inoculating plants with known moniliformin-producing isolates of three Fusarium species. Yields of up to 645 mg/kg were recorded. Isolates of F. acuminatum, F. equiseti, F. fusarioides, and F. moniliforme were found that were highly toxic to ducklings but which did not produce moniliformin.     

A new genus and species of a dendrochirotid holothurian from Southern Africa

A new genus and species of a dendrochirotid holothurian, Pawsonellus africanus , from shallow waters off the east coast of Southern Africa, are described. The new genus is compared with several genera within the family Cucumariidae and it is concluded that it is not closely related to any of them. Although its body wall spicules strongly resemble those of Panningia hyndmani (Thompson), notably the typical form described by Madsen (1942), there are several features which suggest that the two species are not congeneric.