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The hypothesis that a single dominant male (GAA) monopolized all matings within the elephant population of South Africa’s Addo Elephant National Park between 1982 and 1996 was tested using microsatellite analysis. In addition, behavioural data on male musth periods, female oestrous periods, and observations of matings were collected between 1996 and 1999, and used to determine whether there is any behavioural evidence of current mating monopoly by GAA. Exclusion analysis and a likelihood-based approach were employed to assess paternity using genetic data, although low genetic diversity in the Addo elephant population limited the power of these techniques. However, GAA could be excluded as father of a minimum of 34% of calves, and was the most likely father of a maximum of only 28 % of calves. Behavioural data support the genetic data, since there is no indication that GAA monopolizes mating opportunities. Therefore, the hypothesis that a single dominant male has monopolized all matings within the Addo elephant population since 1982 can be rejected.Key words: elephant, paternity, microsatellite, genetic diversity, musth.

To investigate the reasons for the rarity of asexuality, despite the twofold advantage in growth rate of the latter, computer-simulated populations of asexual and sexual individuals of defined genetic composition were allowed to compete at a fixed carrying capacity. Variables included population size, mutation rate, selection coefficient, dominance coefficient, and percentages of mutations which were advantageous. Critical was to allow the two groups to evolve separately for a variable number of generations before being mixed in a single competing population, when one or other population would inevitably go extinct. Multiple reiterations under standard sets of conditions enabled accurate measures of extinction rates, loci carrying mutant alleles, fixed mutant alleles, and fitness values. For all of the above variables, values could readily be found which enabled the sexual population to survive in more than 50% of trials. The diploid state enables dominance to assist in the survival of sexuality....

The quagga project has now been in progress for over 20 years. Its aim, given conclusive molecular evidence that the quagga and the plains zebra, Equus quagga, are conspecific, is the retrieval of the pelage characteristics of the quagga by selective breeding from a selected panel of plains zebra Individuals. The programme has now over 25 third generation progeny, and is starting to produce Individuals with a degree of striping reduction shown by none of the original founders and which approximate the striping pattern shown by at least some of the known museum specimens of quagga. These results Indicate that by the fourth generation the project should have largely succeeded in its aim, and will form the basis of a herd of Individuals which can be displayed in the Western Cape as an Illustration of a phenotype which had disappeared from extant populations of plains zebra.

Molecular analyses of the relationships of placental mammals have shown a progressive congruence between mitogenomic and nuclear phylogenies. Some inconsistencies have nevertheless persisted, notably with respect to basal divergences. The current study has aimed to extend the representation of groups, whose position in the placental tree has been difficult to establish in mitogenomic studies. Both ML (maximum likelihood) and Bayesian analyses identified four basal monophyletic groups, Afroplacentalia (=Afrotheria: Hyracoidea, Proboscidea, Sirenia, Tenrecidea, Tubulidentata, Macroscelidea, Chrysochloridea), Xenarthra, Archontoglires (Primates, Dermoptera, Scandentia, Lagomorpha, Rodentia) and Laurasiaplacentalia (Lipotyphla, Chiroptera, Pholidota, Carnivora, Perissodactyla, Artiodactyla, Cetacea). All analyses joined Archontoglires and Laurasiaplacentalia on a common branch (Boreoplacentalia), but the relationship between Afroplacentalia, Xenarthra and Boreoplacentalia was not conclusively resolved. The phylogenomic hypothesis with a sister group relationship between Notoplacentalia (Afroplacentalia/Xenarthra) and Boreoplacentalia served as the basis for estimating the times of placental divergences using paleontologically well-supported mammalian calibration points. These estimates placed the basal placental divergence between Boreoplacentalia and Notoplacentalia at approximately 102 MYA (million years ago). The current estimates of ordinal placental divergences are congruent with recent estimates based on nuclear data, but inconsistent with paleontological notions that have placed the origin of essentially all placental orders within an interval of 5-10 MY in the early Tertiary. Among less deep divergences the estimates placed the split between Gorilla and Pan/Homo at approximately 11.5 MYA and that between Pan and Homo at approximately 8 MYA. As a consequence of these estimates, which are in accord with recent progress in primate paleontology, the earliest divergences among recent humans become placed approximately 270,000 years ago, i.e. approximately 100,000 years earlier than the traditional age of "Mitochondrial Eve". Comparison between the two new mt genomes of Hylomys suillus (short-tailed gymnure) patently demonstrates the inconsistency that may exist between taxonomic designations and molecular difference, as the distance between these two supposedly conspecific genomes exceeds that of the three elephantid genera Elephas, Mammuthus and Loxodonta. In accordance with the progressive use of the term Placentalia for extant orders and extinct taxa falling within this group we forward new proposals for the names of some superordinal clades of placental mammals.

The world's domestic cats carry patterns of sequence variation in their genome that reflect a history of domestication and breed development. A genetic assessment of 979 domestic cats and their wild progenitors—Felis silvestris silvestris (European wildcat), F. s. lybica (Near Eastern wildcat), F. s. ornata (central Asian wildcat), F. s. cafra (southern African wildcat), and F. s. bieti (Chinese desert cat)—indicated that each wild group represents a distinctive subspecies of Felis silvestris. Further analysis revealed that cats were domesticated in the Near East, probably coincident with agricultural village development in the Fertile Crescent. Domestic cats derive from at least five founders from across this region, whose descendants were transported across the world by human assistance.

The molecular relationship of placental mammals has attracted great interest in recent years. However, 2 crucial and conflicting hypotheses remain, one with respect to the position of the root of the eutherian tree and the other the relationship between the orders Rodentia, Lagomorpha (rabbits, hares), and Primates. Although most mitochondrial (mt) analyses have suggested that rodents have a basal position in the eutherian tree, some nuclear data in combination with mt-rRNA genes have placed the root on the so-called African clade or on a branch that includes this clade and the Xenarthra (e.g., anteater and armadillo). In order to generate a new and independent set of molecular data for phylogenetic analysis, we have established cDNA sequences from different tissues of various mammalian species. With this in mind, we have identified and sequenced 8 housekeeping genes with moderately fast rate of evolution from 22 placental mammals, representing 11 orders. In order to determine the root of the eutherian tree, the same genes were also sequenced for 3 marsupial species, which were used as outgroup. Inconsistent with the analyses of nuclear + mt-rRNA gene data, the current data set did not favor a basal position of the African clade or Xenarthra in the eutherian tree. Similarly, by joining rodents and lagomorphs on the same basal branch (Glires hypothesis), the data set is also inconsistent with the tree commonly favored in mtDNA analyses. The analyses of the currently established sequences have helped examination of problematic parts in the eutherian tree at the same time as they caution against suggestions that have claimed that basal eutherian relationships have been conclusively settled.

Summary We investigated the applicability of microsatellite primers, designed in horses, for use in plains and mountain zebras. Fifteen of the 20 tested horse-isolated primer pairs reliably amplified polymorphic loci in two wild equid species. We used this information to assess whether levels of genetic variation and repeat size differed in species from which microsatellites were isolated and in closely related target species. Target equid species exhibited similar levels of genetic variation to the horse, the species from which primers were originally isolated. We show that ascertainment bias results in lower mean and modal repeat size in target species. The data also provide evidence for a bi-directional mutational constraint in allele size across three equid species.

A molecular phylogenetic investigation was conducted to examine phylogenetic relationships between various members of the catsharks (Chondrichthyes; Carcharhiniformes; Scyliorhinidae), and is the largest chondrichthyan data set yet analysed, consisting of nearly 130,000 nucleotides. Three mitochondrial DNA genes were used to construct the phylogenies, cytochrome b, NADH-2, and NADH-4, with 41 sequences from 18 taxa being novel. These sequences were either used separately or combined into a single data set, and phylogenies were constructed using various methods, however, only the Bayesian inference tree derived from the cytochrome b data set was resolved sufficiently for phylogenetic inferences to be made. Interestingly, the family Scyliorhinidae was not supported by the results and was found to be paraphyletic. The Scyliorhininae and Pentanchinae were supported, whereas the Pentanchini clade was present, but not well supported. The Halaelurini hypothesis was supported with Holohalaelurus identified as the basal genus of that clade, and Haploblepharus edwardsii identified as the basal taxon for that genus. Elsewhere within the Chondrichthyes, the Carcharhiniformes and the Lamniformes were found to be monophyletic, and the Heterodontiformes was placed within the Squalimorphs. The placement of the skates and rays in these analyses support the Batoidea as being sister to the Elasmobranchii.

The endangered mountain zebra (Equus zebra) is endemic to the semi-arid inhospitable mountainous escarpments of southern Africa. The species is divided taxonomically into two geographically separated subspecies, each with differing recent population histories. In Namibia, Hartmann’s mountain zebra (E. z. hartmannae) is common and occurs in large free-ranging populations, whereas in South Africa, prolonged hunting and habitat destruction over the last 300 years has decimated populations of the Cape mountain zebra (E. z. zebra). In this study, we investigate the consequences of these divergent demographic histories for population genetic diversity and structure. We also examine the phylogeographic relationship between the two taxonomic groups. Genetic information was obtained at 15 microsatellite loci for 291 individuals from a total of 10 populations as well as 445 bp of the mitochondrial control region sequence data from 77 individuals. Both model-based and standard analytical approaches were used to examine the data. Both types of marker returned levels of diversity and structure that were consistent with population history. Low genetic variation within individual Cape mountain zebra populations, the characteristic indicator of population fragmentation and drift, was offset by moderate variation in the entire E. z. zebra sample. This implies that higher levels of diversity still exist within the Cape mountain zebra gene pool. A management strategy that entailed the mixing of aboriginal populations is therefore advocated in order to halt the further loss of Cape mountain zebra genetic diversity. Allele frequencies in Hartmann’s mountain zebra were relatively resilient to demographic fluctuations. Due to the high incidence of mitochondrial haplotype sharing between populations, the hypothesis that Cape and Hartmann’s mountain zebra mitochondrial lineages were reciprocally monophyletic was not supported. However, the presence of private alleles at nuclear loci rendered the two subspecies genetically distinct evolutionary significant units.

The Natal long-fingered bat (Miniopterus natalensis) and lesser long-fingered bat (M. fraterculus) are morphologically almost indistinguishable and occur sympatrically over much of their southern African range. This raises the possibility that they are sister taxa. We employed a multidisciplinary approach to examine their taxonomic relationship to one another and to other Miniopterus species, whose global phylogeny requires review. We examined echolocation, morphological, and dietary differences between M. natalensis and M. fraterculus ,a s well as both nuclear and mitochondrial DNA variation between them in the context of a phylogeny incorporating 13 Miniopterus species and subspecies. Despite similarities in their morphology and distribution, M. natalensis and M. fraterculus echolocate at peak frequencies separated by 12 kHz, and both nuclear and mitochondrial DNA markers confirm they are distinct species. Analysis of cytochrome-b (Cytb) sequences further indicates that M. fraterculus and M. natalensis are not sister taxa; M. fraterculus appears to be more closely related to the greater long-fingered bat (M. inflatus). Examination of the global taxonomy of Miniopterus confirms that Schreibers’s long-fingered bat (M. schreibersii) forms a paraphyletic species complex. Furthermore, the miniopterine bats are divided into 2 geographically isolated monophyletic groups, one containing African and European species, and the other taxa from Australasia and Asia. Cytb sequence divergence also suggests that M. natalensis is distinct from the European M. schreibersii. These results support the elevation of M. natalensis to full species rank.

Black and white rhinoceroses are among the most charismatic megaherbivores and have become flagship species for international conservation. They are often subject to intense management that includes being compressed unnaturally in space and density. We present chromosomal and microsatellite evidence to substantiate the first recorded instance of interspecific hybridisation between them. The data suggest that the genetic integrity of the African rhinoceros species probably depends on differences in behavioural and ecological preferences that offer semipermeable reproductive isolation. We caution against the retention of both species in captive and other population situations where disruption of species-specific behaviour patterns may result if there is an unnatural composition in terms of age and sex, and where access to conspecific mates is restricted or absent.

Body composition, isometric quadriceps muscle force output, EMG activity during isometric and SSC activity, and flexibility were assessed in female dancers (n = 11) and physically active controls (n = 11) to investigate quadriceps muscle strength and electromyographic (EMG) activity during isometric and stretch-shortening cycle (SSC) activity in dancers. The dancers had less body fat (21.4% ± 2.8 vs 25.6% ± 3.7, p < 0.01) and were more flexible in the straight-leg raise, ankle plantar flexion and dorsiflexion, elbow flexion and extension and sit-and-reach tests (all p < 0.01) than the controls. The dancers generated greater quadriceps muscle force output during a 5 second maximal voluntary isometric contraction (peak force: 458.9N ± 91.4 vs 327.9N ± 78.2, p < 0.01), but did not jump significantly higher than the controls (37.6 ± 5.5 vs 35.9 ± 3.9 cm, respectively). The dancers generated similar force output to the controls, but with less relative EMG activity, during the squat (p < 0.01), counter-movement (p < 0.05), and drop (p < 0.05) SSC jumps. The dancers had greater quadriceps muscle strength than the controls, but did not jump significantly higher. They used less of their maximum EMG during the jump tests, and hence less of their maximal possible muscle recruitment when jumping than the controls. This may be due to the dancers subconsciously sacrificing their jump height for aesthetics, to training-induced differences in whole limb muscle recruitment patterns, or to training-induced or genetic differences in the elastic components of the dancers’ compared to the controls’ lower limb musculotendinous tissue.

Microsatellite DNA was used to investigatelevels of genetic variability in severelyfragmented populations of the geometrictortoise, Psammobates geometricus, themost endangered tortoise on mainland Africa.Eight microsatellite markers were used toassess genetic variability within and betweenthree naturally occurring populations of P. geometricus. These populations areseparated by the Cape Fold mountain ranges inthe western Cape region of South Africa. Levels of variability were quantified usingallelic diversity, genotypic frequencies andheterozygosity. Evidence for populationsub-structuring was examined using Fstatistics, Rst and δμ2.High levels of variability were found in allthree populations. Low levels of populationdifferentiation were found suggestingsignificant gene flow between the populations.

Sequence data from the intron and spacer of the trnL-F chloroplast region elucidate the phylogenetic relationships of the tribe Diseae (Orchidoideae: Orchidaceae). Within Diseae, 41 species of Disa, two of Brownleea, three of Satyrium, and two of Corycium were included, with five species ofHabenaria sensu lato (Orchideae) and one epidendroid as outgroups. The sequences revealed substitutions and considerable length variation, due mainly to the presence of repeat motifs. Phylogenetic analysis using parsimony revealed five distinct clades. The branching order of the five weakly supported the paraphyly of Diseae, with the successive divergence of Brownleea, Corycium, Habenaria, Satyrium,and Disa. Within the monophyletic Disa, three main groupings appeared, two strongly supported clades representing sect. Racemosae and sect. Coryphaea and the third grouping containing several clades currently grouped into sections based on morphological phylogenies. Some discrepancies between the molecular phylogeny and the phylogeny based on morphological characters may require reevaluation of some of the morphological characters. The presence of different numbers of repeat motifs, both among different taxa and within taxa, indicates that these characters may be phylogenetically informative at the population level. The tribe Diseae dominates the terrestrial orchid flora of southern Africa including 250 of the 466 orchid species on the subcontinent (Linder and Kurzweil, 1999). Diseae encompasses 54% of all orchids endemic to southern Africa, underlining its importance in the local orchid flora. Linder and Kurzweil (1994) recognize five subtribes in the tribe. Of these, Huttonaeinae and Brownleeinae each contain a single genus. Douzery et al. (1999) corroborated the monophyly of the subtribes with the exception of the Coryciinae, which may be diphyletic, and suggested that the tribe itself may be paraphyletic, with Orchideae embedded in Diseae. Almost half of all species in the Diseae belong to the subtribe Disinae. The subtribe was revised taxonomically by Linder in 1981, resulting in a complicated taxonomy of five genera, and many subgenera, sections, and series. However, attempts to establish a wellresolved phylogeny of the subtribe based on morphological data have been unsuccessful (Linder, 1986; Linder and Kurzweil, 1990). Recent morphological work suggested that Brownleea should be excluded from the subtribe, and that Monadenia and Herschelianthe should be included in Disa, thus reducing the subtribe to two genera: Schizodium with 6 species and Disa with 131 species (Johnson, Linder, and Steiner, 1998; Linder and Kurzweil, 1999). Recently, phylogenetic studies in the Orchidaceae have ben1

The amount of genetic differentiation between the African wild cat (Felis lybica) and the domestic cat (F. catus) in southern Africa is not known, but there is concern that interbreeding between the two may have been sufficiently extensive to threaten the status of the wild cat as a genetically distinct population. Eight hypervariable microsatellite loci were therefore used to determine the genetic relationships within and among wild and domestic cat populations. Measures of genetic differentiation, including FST and RST, confirmed significant differentiation between the wild and domestic cat populations and no significant differentiation between two widely separate domestic cat populations. Our data indicate that the level of genetic introgression is lower than previously thought. This enhances the conservation status of the African wild cat and demonstrates the need for the implementation of feral cat control in and around game reserves and rural areas.

Ischaemic preconditioning is a process whereby a period of partial ischaemia, short of a duration resulting in damage, can protect against a subsequent more severe ischaemic episode. The phenomenon was first reported by Murry et al. [1] who showed that short periods of coronary artery occlusion in dogs produced a degree of protection to the heart against more prolonged occlusion. Subsequently it was found that the protective initial ischaemia did not need to be produced in the tissue later exposed to the major ischaemic insult [2], but that cardioprotection, for example, could be effected by short periods of limb ischaemia using a simple blood pressure cuff around the arm. This is termed remote (or distal) ischaemic preconditioning and has become one of the most powerful interventions for reducing myocardial infarction size in ischaemic hearts [3], as, for example, in patients undergoing heart valve surgery. They noted however, as have many others, that incomplete comprehension of the mechanisms underlying the process could be impairing the design of clinical trials and the interpretation of their results.

Genetic variation was measured in 105 African buffalo from four populations in South Africa to investigate the effects of habitat fragmentation. Levels of heterozygosity, allelic diversity and genetic differentiation among populations were quantified using seven polymorphic microsatellite markers. There was a significant correlation between the amount of genetic variation and population size, and differentiation was detected among all populations measured by FST and RST. We used likelihood analysis to infer the effective population sizes of each population and to determine whether the fragmented populations were historically differentiated from one another. The genetic estimates of census size were consistent with historical records, and no historical genetic differentiation could be inferred in the original population before fragmentation. These results are discussed in the light of conservation management of fragmented buffalo populations, particularly where natural gene flow is no longer possible.

Restriction-endonuclease site maps of mitochondrial DNA were constructed for members of the family Bovidae emphasizing species in the Alcelaphinae, Bovinae, and Aepycerotinae. Cladograms weakly supported sister status of the impala, Aepyceros melampus , relative to the Alcelaphinae, and monophyletic status of the Bovini and Tragelaphini. Four members of the Tragelaphini remained an unresolved quadrichotomy, which would be consistent with the inclusion of the eland, Taurotragus oryx , within Tragelaphus . The restriction data are consistent with a radiation for the Tragelaphini at the end of the Miocene.

Cell cultures have been established from 33 individual black rhinoceroses. These were from wild populations from various localities in southern Africa and include representatives from three geographical regions (southwestern, south-central, and eastern) corresponding to currently accepted conservation units, and include individuals previously attributed to one of the four subspecies, Diceros b. minor, D. b. bicornis, D. b. michaeli, and D. b. chobiensis (du Toit et al. 1987). Comparative mitochondrial DNA restriction maps were constructed using 16 restriction enzymes. These showed in each case two site differences between representative individuals from any two of the above geographical regions. Maps were monomorphic within geographical regions and, therefore, have the potential to provide diagnostic markers. The map from a single individual attributed to the D. b. chobiensis subspecies was identical to other individuals (attributed to D. b. minor) in the south-central geographical region. The low amount of genetic diversity implied by these few differences renders it unlikely that problems with outbreeding depression will arise if, given the continuing decline in numbers of black rhinoceroses, it becomes necessary to supplement wild or captive populations with individuals from a different conservation unit in order to avoid inbreeding depression. Se establecieron cultivos de celulas de 33 rinocerontes negros. Estos provinieron de poblaciones salvajes de varias localidades del sur de Africa e incluyen representantes de tres regiones geograficas (Sudoccidental, Sud-central y Oriental) que corresponden a las unidades de conservacion corrientemente aceptadas e incluyen individuos que previamente fueron atribuidos a otras cuatro subespecies, Diceros b. minor, D. b. bicornis, D. b. michaeli y D. b. chobiensis (du Toit, Foose & Cummings, 1987). Se construyeron mapas de restriccion de ADN mitocondrial comparativos usando 16 enzimas de restriccion. En cada caso estos mostraron diferencias en dos sitios entre individuos representantes de un par cualquiera de las regiones geograficas antes mencionadas. Los mapas fueron monomorficos dentro de cada region geografica y por lo tanto tienen el potencial para proveer marcadores diagnosticos. El mapa de un unico individuo que se atribuia a la subespecie D. b. chobiensis fue identico a otros individuos (atribuidos a D. b. minor), en la region geografica Sud-central. El bajo nivel de diversidad genetica que implican estas pocas differencias hace poco probable que surjan problemas de depresion de exogamia si, dada la declinacion continua en el numero de rinocerontes negros, se hace necesario suplementar las poblaciones salvajes o cautivas con individuos de unidades de conservacion diferentes a los efectos de evitar la depresion de endogamia.

Five polymorphic, dinucleotide microsatellite loci have been identified and characterized in Schreibers’ long-fingered bat, Miniopterus schreibersii (Chiroptera: Vespertilionidae). These include three uninterrupted (CA)n repeats, ranging in length from (CA)17 to (CA)19, one interrupted repeat (CA)4(CG)2(CA)13, and one uninterrupted (GA)27 repeat. All loci were highly polymorphic, with 17–20 alleles identified per locus. Observed heterozygosity levels (0.66–0.82) are lower than expected due to homozygote excess, probably caused by pooling of populations, resulting in population substructuring. All five polymorphic loci were also successfully amplified in the closely related M. fraterculus. Two pairs of primers additionally amplified polymorphic microsatellites in Chaerophon sp.

Mitochondrial DNA restriction maps of Diceros bicornis , the black rhinoceros, and Ceratotherium simum , the white rhinoceros, were constructed to provide a basis for population genetic and systematic studies. The sequence divergence between DNA of the two species was calculated to be 6.79% from which it could be estimated that the time of divergence from a common ancestor was ca. 3.4 × 106 years ago. Little intraspecific variation was found in the 24 black rhinoceroses or the 4 white rhinoceroses studied.

The black rhinoceros (Diceros bicornis) is currently one of the most endangered African mammals as a direct result o habitat destruction and intensive poaching. A microsatellite library was constructed to address a number of population genetic questions. This paper describes the isolation of five black rhinoceros microsatellite loci. Three of these loci were found to be polymorphic. In addition, the paper demonstrates the utility for cross-hybridization of these primers in other species of rhinoceros.

DNA fingerprinting involves the use of individual, population or species-specific DNA patterns for providing quantitative or qualitative information for population genetic, forensic and conservation management purposes. Keywords: DNA fingerprinting; ecology; microsatellite; minisatellite; VNTR; RAPD

Black rhinoceros ( Diceros bicornis ) are one of the most endangered mammal species in Africa, with a population decline of more than 96% by the end of the last century. Habitat destruction and encroachment has resulted in fragmentation of the remaining populations. To assist in conservation management, baseline information is provided here on relative genetic diversity and population differentiation among the four remaining recognized subspecies. Using microsatellite data from nine loci and 121 black rhinoceros individuals, and comparing the results with those of other African species affected in similar ways, Diceros bicornis michaeli retained the most genetic diversity (heterozygosity 0.675) compared with Diceros bicornis minor (0.459) and Diceros bicornis bicornis (0.505), suggesting that the duration of the known bottlenecks in these populations has only had a limited impact on diversity. Comparable and moderate degrees of population differentiation were found between D. b. minor, D. b. bicornis and D. b. michaeli. Results from the single sample available of the most endangered subspecies, Diceros bicornis longipes, showed the least diversity of all individuals examined. This information should assist conservation management decisions, especially those affecting population viability assessments and selection of individuals for translocations, and will also facilitate subspecies identification for ex situ individuals of uncertain origin.

Examining patterns of inter-population genetic diversity can provide valuable information about both historical and current evolutionary processes affecting a species. Population genetic studies of flying and migratory species such as bats and birds have traditionally shown minimal population substructure, characterized by high levels of gene flow between populations. In general, strongly substructured mammalian populations either are separated by non-traversable barriers or belong to terrestrial species with low dispersal abilities. Species with female philopatry (the tendency to remain in or consistently return to the natal territory) might show strong substructure when examined with maternally inherited mitochondrial DNA, but this substructure generally disappears when biparentally inherited markers are used, owing to male-mediated gene flow. Male-biased dispersal is considered typical for mammals, and philopatry in both sexes is rare. Here we show strong population substructure in a migratory bat species, and philopatry in both sexes, as indicated by concordance of nuclear and mtDNA findings. Furthermore, the genetic structure correlates with local biomes and differentiation in wing morphology. There is therefore a close correlation of genetic and morphological differentiation in sympatric subspecific populations of this mammalian species.

Widespread hunting had fragmented and severely reduced elephant populations in South Africa by 1900. Elephant numbers increased during the 1900s, although rates of recovery of individual populations varied. The Kruger National Park elephant population increased rapidly, to more than 6000 by 1967, with recruitment boosted by immigration from Mozambique. The Addo Elephant National Park population was reduced to 11 elephants in 1931 and remains relatively small (n = 325). Loss of genetic variation is expected to occur whenever a population goes through a bottleneck, especially when post-bottleneck recovery is slow. Variation at nine polymorphic microsatellite loci was analysed for Kruger and Addo elephants, as well as museum specimens of Addo elephants shot prior to the population bottleneck. Significantly reduced genetic variation and heterozygosity were observed in Addo in comparison to Kruger (mean alleles/locus and H(E): Addo 1.89, 0.18; Kruger 3.89, 0.44). Two alleles not present in the current Addo population were observed in the museum specimens. Addo elephants represent a genetic subset of the Kruger population, with high levels of genetic differentiation resulting from rapid genetic drift. The Kruger population is low in genetic diversity in comparison to East African elephants, confirming this population also suffered an appreciable bottleneck.

Objectives—To measure metabolic rates of the hexose monophosphate shunt (HMPS) in erythrocytes of rhinoceroses, and to test the hypothesis that low concentrations of endogenous ATP in erythrocytes impair HMPS capacity, thereby increasing susceptibility to oxidant-induced hemolysis. Animals—13 black and 3 white rhinoceroses, freeranging in several regions of southern Africa, and 1 Sumatran rhinoceros in US captivity. Procedure—HMPS fluxes were measured in rhinoceros erythrocytes with carbon-labeled glucose in the presence and absence of known HMPS activators. Results—Compared with values for human erythrocytes, mean basal state HMPS fluxes were appreciably lower (22 to 46%) in all 3 rhinoceros species studied. Shunt activators increased HMPS rates approximately 5-fold over basal rates in rhinoceros erythrocytes, compared with increases in humans of 10-fold with ascorbate and 15-fold with methylene blue. Stimulated HMPS rates in human erythrocytes were quantitatively 5- to 10-times greater than those observed in rhinoceros erythrocytes. Overall HMPS catabolic rates were completely independent of intracellular ATP concentrations. Conclusions and Clinical Relevance—HMPS glycolytic and recycling rates and responses to activators are inherently low in erythrocytes from 3 species of rhinoceros, likely contributing to (but not solely responsible for) the high susceptibility of black rhinoceroses to oxidant-induced hemolysis. Slow erythrocyte HMPS capacities were independent of intracellular ATP concentrations, invalidating a current hypothesis regarding the pathogenesis of hemolytic anemia in captive black rhinoceroses. Limitations in HMPS capacities emphasize the importance of protecting rhinoceroses from exposure to drugs, chemicals, toxins, foodstuffs, and other conditions known to increase production of oxidizing metabolites, reactive oxygen species, and free radicals.(Am J Vet Res 2001;62:1113–1117)

Pyrimidine 5' nucleotidase (P5'N-1) deficiency is an autosomal recessive condition causing hemolytic anemia characterized by marked basophilic stippling and the accumulation of high concentrations of pyrimidine nucleotides within the erythrocyte. It is implicated in the anemia of lead poisoning and is possibly associated with learning difficulties. Recently, a protein with P5'N-1 activity was analyzed and a provisional complementary DNA (cDNA) sequence published. This sequence was used to study 3 families with P5'N-1 deficiency. This approach generated a genomic DNA sequence that was used to search GenBank and identify the gene for P5'N-1. It is found on chromosome 7, consists of 10 exons with alternative splicing of exon 2, and produces proteins 286 and 297 amino acids long. Three homozygous mutations were identified in this gene in 4 subjects with P5'N-1 deficiency: codon 98 GAT--GTT, Asp--Val (linked to a silent polymorphism codon 92, TAC--TAT), codon 177, CAA--TAA, Gln--termination, and IVS9-1, G--T. The latter mutation results in the loss of exon 9 (201 bp) from the cDNA. None of these mutations was found in 100 normal controls. The DNA analysis was complicated by P5'N-1 pseudogenes found on chromosomes 4 and 7. This study is the first description of the structure and location of the P5'N-1 gene, and 3 mutations have been identified in affected patients from separate kindreds. (Blood. 2001;97:3327-3332)

A molecular phylogeny of the subfamily Antilopinae was determined using the two mitochondrial DNA (mtDNA) genes cytochrome b and cytochrome c oxidase III. The tribe Antilopini is monophyletic with Antidorcas marsupialis and Litocranius walleri basal to the large genus Gazella. Antilope cervicapra falls within Gazella. This placement would either make Gazella paraphyletic or require that the genus name Gazella be changed to Antilope. Gazella thomsonii is supported as a subspecies of G. rufifrons. Most members of the tribe Neotragini are sister species to the Antilopini, but the Neotragini is rendered paraphyletic by a deep placement of Neotragus moschatus.

Phylogenetic analysis of 14 cetacean species, including members from two baleen whale families and three toothed whale families, was undertaken using restriction site mapping of mitochondrial DNA and using cladistic and distance measures to infer phylogenies. The amount of between-taxa sequence divergence inferred from the data was lower than expected from the standard interpretation of the fossil record, but more consistent with some recent estimates of sequence divergence in cetacean mitochondrial DNA or nuclear DNA. This implies either that the rate of molecular evolution of cetacean DNA is much lower than that of other mammalian orders or that the fossil record of cetaceans requires reinterpretation. The incompleteness of the cetacean fossil record precludes resolution of the paradox at the present time. However, this discrepancy could in part be attributed to the sampling error inherent in the restriction site mapping technique, as comparative studies using the complete mtDNA genome and restriction site data of the blue and fin whales (genus Balaenoptera) indicate that the restriction site maps underestimate sequence divergence by about 40%. In contrast to a recent study suggesting that toothed whales were paraphyletic, with the sperm whales being more closely related to the rorquals than to the other toothed whales, the restriction data tend to support the monophyly of the baleen and the toothed whales, a finding which is consistent with a recent molecular-based study and with morphological and paleontological data. Topologies of the subfamily and generic levels are generally consistent with morphologically based schemes.

Hershko et al. demonstrated in 19671 that rabbit erythrocytes incubated in a high phosphate medium accumulate PRPP. Berman et al. in 19882 defined details of the precise conditions of phosphate concentration, pH and pO2 which control PPRP accumulation in human erythrocytes. Under anoxic conditions xanthine dehydrogenase can be converted to xanthine oxidase which in the presence of hypoxanthine, and molecular oxygen as an electron acceptor, can form superoxide radicals3. If this mechanism contributes to reperfusion injury then removal of hypoxanthine from ischaemic tissue before exposure to oxygen might alleviate injury. In this paper, the ability of erythrocytes to accumulate PPRP under appropriate conditions in vitro is utilised to investigate whether such PPRP ‘primed’ erythrocytes can facilitate the removal of the hypoxanthine which accumulates in ischaemic tissues.

In South Africa, the endemic toad species Bufo pardalis, more commonly known as the leopard toad, was initially described by Hewitt (1935) from Kei Road in the Eastern Cape, as a subspecies of Bufo regularis, Bufo regularis pardalis. It is distributed in two allopatric populations: one that occurs in the extreme southwestern Cape including the Cape Peninsula, Cape Flats and forelands to Hermanus, and the other, larger population that occurs in the Eastern Cape Province from Cape St. Francis to the Kwazulu-Natal border. The smaller Western Cape population is threatened because of the increase in recent years of land development for housing on the peninsula, with corresponding habitat losses (M. I. Cherry, pers. obs.). Hewitt made a distinction between the western and eastern forms based on morphological differences including more brilliant coloration, larger dorsal blotches and broader parotid glands in western specimens. In 1964, Poynton raised Bufo pardalis to specific status but made no comment on Hewitt's distinction between western and eastern forms. Comparisons of laryngeal morphology by Lambiris (1994) provided additional support for species recognition of the two populations. Poynton and Lamibiris (1998) elevated the Western Cape form to specific status as Bufo pantherinus: B. pantherinus was found to have distinctive coloration and markings, as well as unique laryngeal and parotid gland morphology. Differences in call structure have not yet been investigated, but it is intriguing to speculate that the differences in the laryngeal morphology may be reflected by differences in the call structure.

Sequence data from the plastid encoded gene rbcL are used to determine phylogenetic relationships between various lineages in the grasses, with particular emphasis on the subfamily Arundinoideae. Thirty four sequences, producing 155 phylogenetically informative sites, were analysed using both parsimony and distance methods. Cladistic analyses indicate that there are two main lineages: Pooideae (including the Stipeae) and a large clade comprising Panicoideae, Arun- dinoideae, Chloridoideae, and Centothecoideae. The Bambusoideae are unresolved and basal to these two lineages. Relationships within the panicoid, arundinoid, chloridoid, and centothecoid clade indicate that Arundinoideae as presently circumscribed are paraphyletic, as lineages within this subfamily show affinities with all three of the other subfamilies. Despite poor support for some relationships, rbcL appears to be well suited for systematic studies in the Poaceae.

Interaction between the de novo and salvage pathways of pyrimidine metabolism was studied in a line of rat hepatoma cells by co-labelling with [14C]uridine and [3H]orotate. A difference in the ratio of 14 C 3 H between CTP and UTP in the acid-soluble nucleotide pool was reflected in the corresponding ratios in CMP and UMP in RNA, with uridine labelling cytidine nucleotides relatively more effectively than orotate. These results are not compatible with the concept of a single UTP pool, and a new model for pyrimidine anabolic pathways, based on compartmentation of de novo from salvage pathways, is proposed.

DNA was prepared directly from preparations pf papovavirus excreted in the urine of 2 patients on immunosuppressive therapy, without preliminary amplification in cell cultures. EcoRI, BamHI, and HindIII restriction patterns were typical of BK virus DNA and were identical for the two isolates. However, there were significant differences in the sizes of the HindIII fragments when compared with those of standard cell-culture-adapted BK virus strains.

A cytoplasmic polyhedrosis virus (CPV) from Heliothis armigera contains 10 double-stranded RNA genome segments which are all well resolved on polyacrylamide gel electrophoresis. The relationship between log molecular weight and electrophoretic mobility in polyacrylamide gels has been studied using 32 P-labeled CPV RNA, and has been shown to deviate markedly from linearity at the higher molecular weight values. A new relationship between molecular weight and electrophoretic mobility for doubles-tranded RNA has therefore been defined and used to determine the absolute molecular weight of the CPV RNA by comparison with reovirus type 3 RNA.

A patient with hereditary erythrocyte pyrimidine 5′ nucleotidase deficiency was studied to determine the mechanism of accumulation of erythrocyte pyrimidine nucleotides. Estimates of the rate of degradation of uridine nucleotides to diffusable products imply that the high levels found in these patients could not be sustained from the degradative pathways alone. Active synthesis of uridine nucleotides was found to occur in erythrocytes from both patient and control blood samples when either uridine or orotate was used as a substrate. The circulating levels of uridine in the blood are such that sufficient nucleotides to account for the high levels seen in these patients could accumulate in the erythrocytes from biosynthetic pathways alone, quite apart from the contribution from degradation of residual ribosomal RNA. This provides scope for new therapeutic approaches; treatment with allopurinol, however, was found to result in an increase, rather than a decrease, in erythrocyte pyrimidine nucleotides.

The nucleic acids of three viruses infecting Heliothis armigera have been studied. A nuclear polyhedrosis virus and granulosis virus contained double-stranded DNA. A cytoplasmic polyhedrosis virus contained double-stranded RNA, and polyacrylamide gel electrophoresis showed that the genome consisted of 10 discrete double-stranded RNA components.

A re-evaluation of the mobility of double-stranded RNA on polyacrylamide gels over a molecular weight range of 0.46–6.3 · 10 6 was carried out using double-stranded RNAs of: bacteriophage Φ6; virus like particles or mycoviruses of Penicillium chrysogenum, Penicillium stoloniferum and Helminthosporium maydis , and reovirus type III. When the relative mobility on polyacrylamide gels was plotted as a function of log molecular weight, a smooth curve could be drawn which passed through all point. The implications of these findings to the determination of molecular weight of double-stranded RNA by polyacrylamide gel electrophoresis are discussed.

A program is described to perform general DNA sequence analysis on the Hewlett-Packard Model 86/87 microcomputer operating on 128 K of RAM. The following analytical procedures can be performed: 1. display of the sequence, in whole or part, or its complement; 2. search for specified sequences e.g. restriction sites, and in the case of the latter give fragment sizes; 3. perform a comprehensive search for all known restriction enzyme sites; 4. map sites graphically; 5. perform editing functions; 6. base frequency analysis; 7. search for repeated sequences; 8. search for open reading frames or translate into the amino acid sequence and analyse for basic and acidic amino acids, hydrophobicity, and codon usage. Two sequences, or parts thereof, can be merged in various orientations to mimic recombination strategies, or can be compared for homologies. The program is written in HP BASIC and is designed principally as a tool for the laboratory investigator manipulating a defined set of vectors and recombinant DNA constructs.

The genome of a new cytoplasmic polyhedrosis virus (CPV) isolated from Heliothis armigera has been shown to consist of 10 double-stranded RNA segments, as in other CPVs, but the gen

The probable extinction of the last confirmed population of northern white rhinoceros (Ceratotherium simum cottoni) in the world has ignited debate regarding its species status compared to the southern white rhinoceros (Ceratotherium simum simum). Previous studies, based on partial mitochondrial sequences, have reported conflicting results regarding the species status of the northern white rhinoceros. We use whole mitochondrial genomes obtained using Next Generation Sequencing of four northern white rhinoceros and three southern white rhinoceros using novel primers in three overlapping fragments. Phylogenetic relationships were constructed, using Maximum Likelihood, and recovered monophyletic clades for northern white rhinoceros and southern white rhinoceros. The divergence time between the two mitochondrial DNA lineages was estimated to be between 0.46 and 0.97 million years ago using Bayesian inferences. Since there are currently only three surviving northern white rhinoceros individuals these results put into sharp focus the ongoing debate regarding the methods of species definition, and in particular the consequences of such definitions in conservation management of endangered species and subspecies. We conclude that the designation of sub-species status is more applicable to northern and southern white rhinoceros.

The uptake of the pyrimidine nucleotide precursor, orotate, by non-nucleated human erythrocytes is not immediately explicable, (1). During the course of an investigation into the origin of the increased erythrocyte nucleotides seen in hereditary ythrocyte pyrimidine 5′nucleotidase deficiency, rapid uptake of 14C orotate and its conversion to uridine nucleotides by normal red cells was observed (Figure 1(a) A). Moreover, free uridine was present within the cells and accumulated in significant quantities in the medium (Figure 2).

Intercellular gap-junctional communication was measured using [14C]citrulline incorporation in co-cultures of argininosuccinate lyase-deficient human fibroblasts and argininosuccinate synthetase-deficient Chinese Hamster V79 cells. As previously shown, in this system junctional communication is completely inhibited by the tumor promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA). In the absence of extracellular calcium, TPA inhibition was less pronounced. However, synergism with calcium ionophore A23187 could not be demonstrated. Chlorpromazine, trifluoperazine and 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester partially antagonised the effect of TPA. No antagonism was demonstrable between calmidazolium and TPA. Treatment of co-cultures with exogenous phospholipase C or 1-oleoyl-2-acetylglycerol (OAG) resulted in communication inhibition, suggesting that protein kinase C activation is involved in the mechanism of phorbol ester-mediated communication inhibition. However co-cultures which had been made refractory to TPA by prolonged exposure to high concentrations remained sensitive to inhibition by phospholipase C and OAG. These results suggest either that diacylglycerol can produce other effects independent of protein kinase C activation, or that refractoriness to phorbol esters is not simply due to a decrease in the amount of protein kinase C.