Persistent millennial-scale climatic variability over the past 25,000 years in Southern Africa

Ehrharta Thunb. is a genus of Gondwanaland distribution with its centre of diversity in the winter rainfall Fynbos Biome of southern Africa. In recent subfamily treatments Ehrharta has proved difficult to place satisfactorily, and during the past five years it has been moved between Bambusoideae and Arundinoideae. However, most previous systematic studies using cryptic characters have covered only four taxa out of about 35. The present study includes all African taxa, and demarcates seven species groups on the basis of both spikelet morphology and leaf blade anatomy. Parallelism and/or convergence in vegetative macromorphology within and between the species groups is widespread, and is similar, in some cases, to adaptations found in other plant families in the Fynbos Biome. However, these macromorphological trends are not reflected in the leaf anatomy. Leaf anatomy is generally consistent with the spikelet morphology. Some anatomical differences between the species groups in Ehrharta appear to be as great as differences between taxa of much higher ranks elsewhere in the Poaceae. This wide range of variability may be related to an early divergence of Ehrharteae from other grasses, as suggested by the Gondwanaland distribution, and may explain the difficulty of placing this fascinating yet baffling genus in a subfamily.

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New taxa, new records and name changes for southern African plants

Bothalia ◽

10.4102/abc.v18i2.1052 ◽

1988 ◽

Vol 18 (2) ◽

pp. 293-304 ◽

Cited By ~ 3

Author(s):

G. E. Gibbs Russell ◽

W. G. Welman ◽

G. Germishuizen ◽

E. Retief ◽

B. J. Pienaar ◽

...

Keyword(s):

Southern Africa ◽

Vascular Plants ◽

New Records ◽

The Past ◽

Past Half Century ◽

Infraspecific Taxa ◽

African Plants ◽

New Research ◽

Name Changes ◽

Past Half

Alterations to the inventory of about 24 000 species and infraspecific taxa of bryophytes and vascular plants in southern Africa are reported for the year 1987. The inventory, as presently maintained in the Taxon component of the PRECIS system, contains the accepted name for each taxon, synonyms previously in use as accepted names during the past half-century, and literature references necessary to identify species in each genus and to establish the synonymy. The inventory is updated as new research affecting plant classification in southern Africa is published. During 1987 there were 678 alterations, representing about 2,8% of the total number of taxa.a

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The taxonomic position of C3 and C4 Alloteropsis semialata (Poaceae) in southern Africa

Bothalia ◽

10.4102/abc.v14i2.1160 ◽

1983 ◽

Vol 14 (2) ◽

pp. 205-213 ◽

Cited By ~ 8

Author(s):

G. E. Gibbs Russell

Keyword(s):

Southern Africa ◽

Leaf Blade ◽

Morphological Characters ◽

Taxonomic Position ◽

Grass Species ◽

The Past ◽

Photosynthetic Pathways ◽

Voucher Specimens

Alloteropsis semialata (R. Br.) Hitchc. sensu Chippindall (1955) and Clayton (in press) is the only known grass species in which elements with both non-Kranz and Kranz leaf blade anatomy, and therefore with C3 and C4 photosynthetic pathways are included. In the past, two taxa had been recognized, but the characters used to separate them were found to be unreliable, so they were united. However, study of voucher specimens for anatomical and physiological work has shown that C3 and C4 taxa may be separated on the basis of morphological characters that differ from those considered in the past. Therefore, two taxa are again recognized, this time at the rank of subspecies, and the name Alloteropsis semialata subsp. eckloniana (Nees) Gibbs Russell stat. nov. is published.

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Millennial-scale denudation rates in the Himalaya of Far Western Nepal

10.5194/esurf-2019-7 ◽

2019 ◽

Author(s):

Lujendra Ojha ◽

Ken L. Ferrier ◽

Tank Ojha

Keyword(s):

Stream Power ◽

Denudation Rate ◽

The Past ◽

Cosmogenic Nuclide ◽

Northern India ◽

Denudation Rates ◽

Cosmogenic 10Be ◽

Channel Steepness ◽

The Himalaya ◽

Millennial Scale

Abstract. Over the past two decades, rates and patterns of Himalayan denudation have been documented through numerous cosmogenic nuclide measurements in central and eastern Nepal, Bhutan, and northern India. To date, however, few denudation rates have been measured in Far Western Nepal – a ~ 300-km-wide region near the center of the Himalayan arc – which presents a significant gap in our understanding of Himalayan denudation. Here we report new catchment-averaged millennial-scale denudation rates inferred from cosmogenic 10Be in fluvial quartz at seven sites in Far Western Nepal. The inferred denudation rates range from 385 ± 31 t km−2 yr−1 (0.15 ± 0.01 mm yr −1) to 8737 ± 2908 t km−2 yr−1 (3.3 ± 1.1 mm yr−1), and, in combination with our analyses of channel topography, are broadly consistent with previously published relationships between catchment-averaged denudation rates and normalized channel steepness across the Himalaya. These data show a weak correlation with catchment-averaged specific stream power, consistent with a Himalaya-wide compilation of previously published stream power values. Together, these observations are consistent with a dependence of denudation rate on both tectonic and climatic forcings, and represent a first step toward filling an important gap in denudation rate measurements in Far Western Nepal.

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Abrupt Termination of Employee Contracts In a Democratic State: The Case of Botswana

Journal of Public Administration and Governance ◽

10.5296/jpag.v2i4.2611 ◽

2012 ◽

Vol 2 (4) ◽

pp. 71

Author(s):

Baakile Motshegwa ◽

Keratilwe Bodilenyane

Keyword(s):

Southern Africa ◽

Trade Unions ◽

The State ◽

The Past ◽

Democratic State ◽

Essential Services ◽

Disciplinary Procedures ◽

The Government

Botswana has in the past received accolades of being the most peaceful country in Southern Africa. Any disturbance of this peace is either shunned or seen as a departure from the norm. The advent of trade unions in Botswana has always been looked at with suspicion and they have been seen as militant, which is contrary to the peaceful existence the country has enjoyed regardless of the fact that it is surrounded by countries that have been to war at some point in their history. Therefore, the state has made it a point that any sign of unrest is severely dealt with by the government. Some employees were dismissed un-procedurally as disciplinary procedures were not followed and the court ruled in the employee’s favour in 2012. The majority of those dismissed were from the essential services sections of government even though at the beginning some were released through the strike rules agreement between government and unions. Laid down disciplinary rules and procedures of having a hearing were not followed.

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Ancient genomes reveal complex patterns of population movement, interaction, and replacement in sub-Saharan Africa

Science Advances ◽

10.1126/sciadv.aaz0183 ◽

2020 ◽

Vol 6 (24) ◽

pp. eaaz0183 ◽

Cited By ~ 2

Author(s):

Ke Wang ◽

Steven Goldstein ◽

Madeleine Bleasdale ◽

Bernard Clist ◽

Koen Bostoen ◽

...

Keyword(s):

Southern Africa ◽

Sub Saharan Africa ◽

The Past ◽

Genome Wide ◽

Movement Interaction ◽

Genome Wide Data ◽

Sub Saharan ◽

Population Interactions ◽

Eastern And Southern Africa ◽

Complex Trajectories

Africa hosts the greatest human genetic diversity globally, but legacies of ancient population interactions and dispersals across the continent remain understudied. Here, we report genome-wide data from 20 ancient sub-Saharan African individuals, including the first reported ancient DNA from the DRC, Uganda, and Botswana. These data demonstrate the contraction of diverse, once contiguous hunter-gatherer populations, and suggest the resistance to interaction with incoming pastoralists of delayed-return foragers in aquatic environments. We refine models for the spread of food producers into eastern and southern Africa, demonstrating more complex trajectories of admixture than previously suggested. In Botswana, we show that Bantu ancestry post-dates admixture between pastoralists and foragers, suggesting an earlier spread of pastoralism than farming to southern Africa. Our findings demonstrate how processes of migration and admixture have markedly reshaped the genetic map of sub-Saharan Africa in the past few millennia and highlight the utility of combined archaeological and archaeogenetic approaches.

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Redescription of Haemaphysalis (Rhipistoma) elliptica (Koch, 1844), an old taxon of the Haemaphysalis (Rhipistoma) leachi group from East and southern Africa, and of Haemaphysalis (Rhipistoma) leachi (Audouin, 1826) (Ixodida, Ixodidae

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v74i3.122 ◽

2007 ◽

Vol 74 (3) ◽

Cited By ~ 45

Author(s):

D.A. Apanaskevich ◽

I.G. Horak ◽

J-L. Camicas

Keyword(s):

East Africa ◽

Southern Africa ◽

Junior Synonym ◽

Past Century ◽

Nomen Nudum ◽

Immature Stages ◽

The Past ◽

Wild Carnivores ◽

First Time

Koch (1844) originally described only the male of Haemaphysalis (Rhipistoma) elliptica (Koch, 1844), which he named Rhipistoma ellipticum. For the past century, however, this name has been considered a junior synonym of Haemaphysalis (Rhipistoma) leachi (Audouin, 1826), or a nomen nudum. We redescribe here the male and larva of H. (R.) elliptica and describe the female and nymph for the first time. Our redescription is based on the male holotype, plus numerous specimens from southern and East Africa. The adults of this tick parasitize domestic and wild carnivores, and the immature stages infest rodents in these regions. For comparative purposes redescriptions of all parasitic stages of H. (R.) leachi are provided. It parasitizes the same hosts as H. (R.) elliptica in Egypt, and in northeastern, Central, West and East Africa.

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