scholarly journals Diversification of African Rainforest Restricted Clades: Piptostigmateae and Annickieae (Annonaceae)

Diversity ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 227 ◽  
Author(s):  
Baptiste Brée ◽  
Andrew J. Helmstetter ◽  
Kévin Bethune ◽  
Jean-Paul Ghogue ◽  
Bonaventure Sonké ◽  
...  
Keyword(s):  
East Africa ◽  
East African ◽  
African Species ◽  
Extinction Rates ◽  
West Central ◽  
History Of ◽  
Best Fitting ◽  
The One ◽  
Extinction Events ◽  
The Impact

African rainforests (ARFs) are species rich and occur in two main rainforest blocks: West/Central and East Africa. This diversity is suggested to be the result of recent diversification, high extinction rates and multiple vicariance events between west/central and East African forests. We reconstructed the diversification history of two subtribes (Annickieae and Piptostigmateae) from the ecologically dominant and diverse tropical rainforest plant family Annonaceae. Both tribes contain endemic taxa in the rainforests of West/Central and East Africa. Using a dated molecular phylogeny based on 32 nuclear markers, we estimated the timing of the origin of East African species. We then undertook several diversification analyses focusing on Piptostigmateae to infer variation in speciation and extinction rates, and test the impact of extinction events. Speciation in both tribes dated to the Pliocene and Pleistocene. In particular, Piptostigma (13 species) diversified mainly during the Pleistocene, representing one of the few examples of Pleistocene speciation in an African tree genus. Our results also provide evidence of an ARF fragmentation at the mid-Miocene linked to climatic changes across the region. Overall, our results suggest that continental-wide forest fragmentation during the Neogene (23.03–2.58 Myr), and potentially during the Pliocene, led to one or possibly two vicariance events within the ARF clade Piptostigmateae, in line with other studies. Among those tested, the best fitting diversification model was the one with an exponential speciation rate and no extinction. We did not detect any evidence of mass extinction events. This study gives weight to the idea that the ARF might not have been so negatively impacted by extinction during the Neogene, and that speciation mainly took place during the Pliocene and Pleistocene.

Archeology and Reconstructing History in the Kenya Highlands: the Intellectual Legacies of G.W.B. Huntingford and Louis S.B. Leakey

2007 ◽  
Vol 34 ◽  
pp. 297-320
Author(s):  
J.E.G. Sutton
Keyword(s):  
Rift Valley ◽  
African History ◽  
East African ◽  
Colonial Era ◽  
History Of ◽  
Basic Approaches ◽  
The One ◽  
The Impact ◽  
Neolithic Cultures ◽  
Intellectual Climate

A preceding article examined the ethnographic, linguistic and archeological enquiries of G.W.B. Huntingford (1901-1978) and L.S.B. Leakey (1903-1972) in the Kenya highlands in the “high colonial” era of the 1920s and 1930s—the one, a young settler, researching independently in the Kalenjin region west of the Rift Valley, the other brought up on an Anglican mission station in Kikuyu country to the east and then, as an ambitious prehistorian, concentrating his activities in the Rift itself. That article pointed to their contrasting approaches to these disciplines, observing how each in his own way separately compartmentalized his anthropology from his archeology, with the result that any sense of the history of the existing peoples whom they studied-Nandi and Kikuyu-was effectively denied. This sequel examines their archeology more critically, beginning with their basic approaches and methods, and then tracing the impact of their work on subsequent scholarship and research endeavors, and especially on those anxious to reconstruct East African history in the changing intellectual climate leading to Independence.The article concerns itself therefore with what Leakey in the late 1920s designated “Neolithic cultures” in the Nakuru-Elmenteita basin within the elevated stretch of the Rift Valley, to which subject Mary Leakey subsequently contributed, leading to Sonia Cole's essays at synthesis in the 1950s/1960s; and also with the Azanian hypothesis of Huntingford, which was rediscovered by Basil Davidson in the late 1950s and, with some deft transformation, catapulted centerstage for an emerging picture of East African history of a positive and enlightened sort.

scholarly journals What’s New About Muslim Ismaili Transnationalism? Comparing Business Practices in British East Africa, Colonial Mozambique and Contemporary Angola

2013 ◽  
Vol 12 (3) ◽  
pp. 215-244 ◽  
Author(s):  
Susana Salvaterra Trovão ◽  
Filomena Batoréu
Keyword(s):  
East Africa ◽  
Business Practices ◽  
Economic Activities ◽  
East African ◽  
Potential Conflict ◽  
Face To Face ◽  
Nation States ◽  
History Of ◽  
Postcolonial Africa ◽  
The Impact

Abstract The way in which the history of colonialism might link up with the formation of postcolonial migrant identities remains insufficiently examined. Through a comparison between transnational business practices of Khoja Ismaili Muslim settled in the British and Portuguese colonial territories of East Africa and in contemporary Angola, the present paper aims to discuss the impact of colonial experiences in the configuration of postcolonial business cultures. Articulating several guiding empirical questions, we will attempt to show that the continuing centrality of the nation-states in which Ismaili transnational economic activities are embedded, the notion of a disadvantageous network closure, concomitant with the importance of face-to-face contacts, the mutual trust and understanding sustained through personal relations, and the tendency for national loyalty to prevail over religious belonging (whenever any potential conflict between the two exists) constitute crucial dimensions of an accumulated colonial knowledge which is significant in the analysis of the Ismaili competitive advantage in postcolonial Africa. This argument will be developed on the basis of a multi-sited ethnographic research. The U.K. and Portugal emerged as a strategic passage for our encounters with East African Ismailis from former British and Portuguese colonial territories. The current Angolan context, absent from the available literature, was selected as a postcolonial term of comparison.

The War of Legs

Transfers ◽  
2015 ◽  
Vol 5 (2) ◽  
pp. 102-120
Author(s):  
Michael Pesek
Keyword(s):  
World War I ◽  
Medical Care ◽  
East Africa ◽  
Transport Infrastructure ◽  
World War ◽  
East African ◽  
Colonial State ◽  
History Of ◽  
Main Factors ◽  
Belgian Congo

This article describes the little-known history of military labor and transport during the East African campaign of World War I. Based on sources from German, Belgian, and British archives and publications, it considers the issue of military transport and supply in the thick of war. Traditional histories of World War I tend to be those of battles, but what follows is a history of roads and footpaths. More than a million Africans served as porters for the troops. Many paid with their lives. The organization of military labor was a huge task for the colonial and military bureaucracies for which they were hardly prepared. However, the need to organize military transport eventually initiated a process of modernization of the colonial state in the Belgian Congo and British East Africa. This process was not without backlash or failure. The Germans lost their well-developed military transport infrastructure during the Allied offensive of 1916. The British and Belgians went to war with the question of transport unresolved. They were unable to recruit enough Africans for military labor, a situation made worse by failures in the supplies by porters of food and medical care. One of the main factors that contributed to the success of German forces was the Allies' failure in the “war of legs.”

scholarly journals Epidemic malaria and warmer temperatures in recent decades in an East African highland

2010 ◽  
Vol 278 (1712) ◽  
pp. 1661-1669 ◽  
Author(s):  
David Alonso ◽  
Menno J. Bouma ◽  
Mercedes Pascual
Keyword(s):  
Climate Change ◽  
East Africa ◽  
Nonlinear Response ◽  
Climate Change Impacts ◽  
Human Model ◽  
Recent Past ◽  
East African ◽  
Highly Nonlinear ◽  
The Impact

Climate change impacts on malaria are typically assessed with scenarios for the long-term future. Here we focus instead on the recent past (1970–2003) to address whether warmer temperatures have already increased the incidence of malaria in a highland region of East Africa. Our analyses rely on a new coupled mosquito–human model of malaria, which we use to compare projected disease levels with and without the observed temperature trend. Predicted malaria cases exhibit a highly nonlinear response to warming, with a significant increase from the 1970s to the 1990s, although typical epidemic sizes are below those observed. These findings suggest that climate change has already played an important role in the exacerbation of malaria in this region. As the observed changes in malaria are even larger than those predicted by our model, other factors previously suggested to explain all of the increase in malaria may be enhancing the impact of climate change.

scholarly journals A Survey of Techniques for Constructing Chinese Knowledge Graphs and Their Applications

2018 ◽  
Vol 10 (9) ◽  
pp. 3245 ◽  
Author(s):  
Tianxing Wu ◽  
Guilin Qi ◽  
Cheng Li ◽  
Meng Wang
Keyword(s):  
Artificial Intelligence ◽  
Question Answering ◽  
Knowledge Representation And Reasoning ◽  
Knowledge Graph ◽  
Development History ◽  
One Belt One Road ◽  
History Of ◽  
Knowledge Graphs ◽  
The One ◽  
The Impact

With the continuous development of intelligent technologies, knowledge graph, the backbone of artificial intelligence, has attracted much attention from both academic and industrial communities due to its powerful capability of knowledge representation and reasoning. In recent years, knowledge graph has been widely applied in different kinds of applications, such as semantic search, question answering, knowledge management and so on. Techniques for building Chinese knowledge graphs are also developing rapidly and different Chinese knowledge graphs have been constructed to support various applications. Under the background of the “One Belt One Road (OBOR)” initiative, cooperating with the countries along OBOR on studying knowledge graph techniques and applications will greatly promote the development of artificial intelligence. At the same time, the accumulated experience of China in developing knowledge graphs is also a good reference to develop non-English knowledge graphs. In this paper, we aim to introduce the techniques of constructing Chinese knowledge graphs and their applications, as well as analyse the impact of knowledge graph on OBOR. We first describe the background of OBOR, and then introduce the concept and development history of knowledge graph and typical Chinese knowledge graphs. Afterwards, we present the details of techniques for constructing Chinese knowledge graphs, and demonstrate several applications of Chinese knowledge graphs. Finally, we list some examples to explain the potential impacts of knowledge graph on OBOR.

scholarly journals Swiss Architectural Origins, Le Corbusier, and the Pātaka of Lake Horowhenua (1845)

2014 ◽  
Vol 11 ◽  
pp. 72-81
Author(s):  
Peter Wood
Keyword(s):  
Le Corbusier ◽  
Direct Influence ◽  
The North ◽  
The Pacific ◽  
History Of ◽  
The One ◽  
Swiss Lake ◽  
Richard Taylor ◽  
The Impact ◽  
The Town

In April, 1845, the Rev. Richard Taylor passed through the area of the North Island now marked by the town of Levin. At this time, he described Lake Horowhenua as being of singular appearance for the small storehouses built over the water on poles. As was his predilection, Taylor made a drawing of the lake huts, a version of which was belatedly included in the second edition of his most important literary contribution, Te Ika-a-Māui (1870). This image would have remained as little more than a questionable curiosity was it not for Messrs Black Bros who, in the course of exploring the lake bed for Māori artefacts in 1932, legitimised Taylor's observation with their discovery of the submerged architectural remains of an aquatic hut. Nonetheless, almost a century after Taylor's original diary entry, GL Adkin, writing for The Journal of the Polynesian Society, lamented the neglect shown toward these remarkable structures, and which he cited as just one example of the "tantalising gaps" in the recorded history of Māori custom and culture. Sadly, it is well beyond the scope of this research to properly redress the historical neglect shown toward lake pātaka. What I do wish to do is to link these structures to an event on the shores of the Lake of Zurich, Switzerland, when Dr Ferdinand Keller noticed some half-submerged piles in 1854. Upon these remains Keller made a great, if erroneous, case for primitive "pile-work habitations" in the Swiss lakes. The impact of this argument cannot be understated. It became the privileged model for architectural origins in the German and French parts of Switzerland, and by the 1890s it was a part of standard teaching texts in Swiss schools, where it was firmly inculcated into the curriculum at the time that Charles Edouard Jeanneret was a child. This in turn has led Vogt to suggest that, in Keller's "dwellings on the water," Le Corbusier found a Primitive Hut typology that underpinned all his architectural thinking, and which is made most explicit in his principled use of piloti. What makes this all the more involved is that Keller, in searching for examples to visualise the construction of the Swiss lake dwellings, turned to the Pacific (which he categorised as at a developmental stage of architectural evolution akin to early Europe). In this paper I identify the exact etching by Louis Auguste de Sainson that Keller took for direct influence. The problem, however, is that de Sainson depicted a conventional whare built on land, and Keller transposed it to the water. So we have on the one side of this paper an authentic lake whare that is all but forgotten, and a famed European lake-hut that is all but Māori, and between the two is the figure of Le Corbusier who may or may not have unknowingly based one on his major innovations on influences found in the pātaka of Lake Horowhenua.

3. Extinction in the past

2019 ◽  
pp. 33-50
Author(s):  
Paul B. Wignall
Keyword(s):  
Fossil Record ◽  
The Past ◽  
Extinction Rates ◽  
History Of ◽  
Extinction Events

Despite the less-than-perfect nature of the fossil record, it still provides a unique window on the history of life, and reveals that there have been dramatic fluctuations in extinction intensities since complex life evolved around 600 million years ago. ‘Extinction in the past’ considers Jack Sepkoski’s database compiled in the 1980s, and his series of highly informative charts showing both diversity and extinction rates since the start of the Cambrian Period 541 million years ago. The calculation of extinction rates and the improved dating of extinction events are discussed, along with the extinction trends that can be observed. Fossils also provide valuable evidence on the nature of selection during extinction.

The Historiographical Legacy of Salo Wittmayer Baron: The Medieval Period

AJS Review ◽  
1993 ◽  
Vol 18 (1) ◽  
pp. 29-37
Author(s):  
Robert Chazan
Keyword(s):  
Twentieth Century ◽  
North America ◽  
Middle Ages ◽  
Jewish History ◽  
Essential Element ◽  
Medieval Period ◽  
History Of ◽  
The One ◽  
Almost All ◽  
The Impact

The impact of Salo Wittmayer Baron on the study of the history of the Jews during the Middle Ages has been enormous. This impact has, in part, been generated by Baron's voluminous writings, in particular his threevolume The Jewish Community and–even more so–his eighteen-volume Social and Religious History of the Jews. Equally decisive has been Baron's influence through his students and his students' students. Almost all researchers here in North America currently engaged in studying aspects of medieval Jewish history can surely trace their intellectual roots back to Salo Wittmayer Baron. In a real sense, many of Baron's views have become widey assumed starting points for the field, ideas which need not be proven or irgued but are simply accepted as givens. Over the next decade or decades, hese views will be carefully identified and reevaluated. At some point, a major study of Baron's legacy, including his influence on the study of medieval Jewish history, will of necessity eventuate. Such a study will have, on the one hand, its inherent intellectual fascination; at the same time, it will constitute an essential element in the next stages of the growth of the field, as it inevitably begins to make its way beyond Baron and his twentieth-century ambience.

A new species of Stenampyx Karsch, 1890 from East Africa (Orthoptera: Tettigoniidae, Pseudophyllinae, Phyllomimini)—evidence of a former connection of West-Central and East African forests

Zootaxa ◽  
2020 ◽  
Vol 4763 (4) ◽  
pp. 593-599
Author(s):  
CLAUDIA HEMP
Keyword(s):  
New Species ◽  
East Africa ◽  
West African ◽  
East African ◽  
West Central ◽  
Close Relationship ◽  
A New Species

A new Stenampyx, S. viridiflavum n. sp., is described from Tanzania. Stenampyx was monotypic and known from Central to West African forests. As with the genus Pseudotomias Hemp, the newly described species in Stenampyx shows a close relationship to the Central and East African forest fauna. 

scholarly journals A 17-My-old whale constrains onset of uplift and climate change in east Africa

2015 ◽  
Vol 112 (13) ◽  
pp. 3910-3915 ◽  
Author(s):  
Henry Wichura ◽  
Louis L. Jacobs ◽  
Andrew Lin ◽  
Michael J. Polcyn ◽  
Fredrick K. Manthi ◽  
...  
Keyword(s):  
Indian Ocean ◽  
East Africa ◽  
Sea Level ◽  
Drainage System ◽  
Beaked Whale ◽  
East African ◽  
Surface Uplift ◽  
The Indian Ocean ◽  
Mantle Processes ◽  
The Impact

Timing and magnitude of surface uplift are key to understanding the impact of crustal deformation and topographic growth on atmospheric circulation, environmental conditions, and surface processes. Uplift of the East African Plateau is linked to mantle processes, but paleoaltimetry data are too scarce to constrain plateau evolution and subsequent vertical motions associated with rifting. Here, we assess the paleotopographic implications of a beaked whale fossil (Ziphiidae) from the Turkana region of Kenya found 740 km inland from the present-day coastline of the Indian Ocean at an elevation of 620 m. The specimen is ∼17 My old and represents the oldest derived beaked whale known, consistent with molecular estimates of the emergence of modern strap-toothed whales (Mesoplodon). The whale traveled from the Indian Ocean inland along an eastward-directed drainage system controlled by the Cretaceous Anza Graben and was stranded slightly above sea level. Surface uplift from near sea level coincides with paleoclimatic change from a humid environment to highly variable and much drier conditions, which altered biotic communities and drove evolution in east Africa, including that of primates.

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