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1.
This paper re-enters the contested discussion surrounding the Indian Enigma, the high prevalence of chronic undernutrition in India relative to sub-Saharan Africa. Jayachandran & Pande (JP) argue that the key to the Indian Enigma lies in the worse treatment of higher birth order children, particularly girls. Analyzing new data, and taking into account issues relating to robustness to model specification, weighting and existing critiques of JP., we find: (1) Parameter estimates are sensitive to sampling design and model specification; (2) The gap between the heights of pre-school African and Indian children is closing; (3) The gap does not appear to be driven by differential associations by birth order and child sex; (4) The remaining gap is associated with differences in maternal heights. If Indian women had the heights of their African counterparts, pre-school Indian children would be taller than pre-school African children; and (5) Once we account for survey design, sibling size and maternal height, the coefficient associated with being an Indian girl is no longer statistically significant. 相似文献
2.
R. M. McDowall 《Journal of Biogeography》2005,32(1):49-62
Aim This paper describes the biogeographical setting of the Falkland Islands, in the context of the relationships of the islands’ biota to other sub‐Antarctic/cold temperate lands. Location The analysis focuses primarily on the Falklands biota, and explores its relationships to those of Patagonian South America and South Africa, other southern lands and the islands of the sub‐Antarctic Pacific, Indian and Atlantic Oceans. Methods The study derives largely from literature sources on the biota and geological history of the Falkland Islands. Results The animals and plants known from the Falkland Islands exhibit strong affinities with those of Patagonian South America, and especially Tierra del Fuego; additional affinities are with various remote islands of the sub‐Antarctic, as well as New Zealand and to a lesser extent Australia; often these are shared with Patagonia. While the biotic affinities might be interpreted, by some, as indicating a former Gondwanan/South American geological connection of the Falklands, geological evidence points to the Falklands formerly having a land connection to south‐eastern South Africa. Only faint hints of a South African biotic connection remain. The historical biotic and geological connections of the Falklands thus conflict. Moreover, the Falklands biota is so strongly Patagonian that derivation of that biota is best seen as resulting from dispersal, much of it probably recent. This dispersal biota appears to have replaced, and perhaps displaced, the South African biota present on the islands as they detached from South Africa and drifted across the south Atlantic Ocean, as it opened up as South America and Africa drifted apart. 相似文献
3.
Culleton R Coban C Zeyrek FY Cravo P Kaneko A Randrianarivelojosia M Andrianaranjaka V Kano S Farnert A Arez AP Sharp PM Carter R Tanabe K 《PloS one》2011,6(12):e29137
Plasmodium vivax, the second most prevalent of the human malaria parasites, is estimated to affect 75 million people annually. It is very rare, however, in west and central Africa, due to the high prevalence of the Duffy negative phenotype in the human population. Due to its rarity in Africa, previous studies on the phylogeny of world-wide P. vivax have suffered from insufficient samples of African parasites. Here we compare the mitochondrial sequence diversity of parasites from Africa with those from other areas of the world, in order to investigate the origin of present-day African P. vivax. Mitochondrial genome sequencing revealed relatively little polymorphism within the African population compared to parasites from the rest of the world. This, combined with sequence similarity with parasites from India, suggests that the present day African P. vivax population in humans may have been introduced relatively recently from the Indian subcontinent. Haplotype network analysis also raises the possibility that parasites currently found in Africa and South America may be the closest extant relatives of the ancestors of the current world population. Lines of evidence are adduced that this ancestral population may be from an ancient stock of P. vivax in Africa. 相似文献
4.
Eleusine coracana ssp. coracana (finger millet, eleusine) is widely distributed in Africa and India as a cereal. The crop is cultivated in diverse eco-geographical areas. Over this range of distribution, eleusine displays high variability in vegetative, floral and seed morphology. The intent of this study is to establish correlations between morphology and distribution, and to determine the intraspecific taxonomy of the crop. Three eco-geographical races were determined: (1) an African highland race which is cultivated in the East African highlands, (2) a lowland race which is grown in the lowlands of Africa and South India, and (3) an Indian race with its center of distribution in Northeast India. In addition to these basic races, an Indian highland type was identified. The African highland race is the most primitive from which the lowland race evolved. The latter race was subsequently introduced to southern India where a secondary center of diversity became established. The Indian race originated from the lowland race, while the North Indian highland type can be derived from either or both of the two basic races in India. This study indicated that natural selection played a major role in the evolution of the crop. Artificial selection, although significant, was restricted within the limits imposed on it by the ultimate adaptation of the races to their environments. 相似文献
5.
J. Caujapé-Castells R. K. Jansen J. Pedrola-Monfort N. Membrives 《Plant Systematics and Evolution》2002,232(1-2):73-88
We examined patterns of cpDNA RFLP variability using 21 restriction endonucleases in 21 populations of Androcymbium that represent 12 endemic species distributed in the winter rainfall areas of South Africa to explore the diversification
of the genus in its area of maximum species diversity. Our results are supportive of a diversification landscape characterized
by continued opportunistic short-range invasion, naturalization, and rapid speciation, in which the selective action of the
different environments where Androcymbium species occur determined their colonization success and subsequent short-range geographic expansion. The historical presence
of fire, the constraint imposed by the low concentration of nutrients throughout southwestern South Africa and the different
reproductive capabilities of Androcymbium species have also likely stimulated species' diversification. Our divergence time estimates bolster the view that speciation
of South African Androcymbium initiated in the late Eocene, intensified in the Oligocene and proceeded more sporadically during the Miocene. These chronological
estimates also substantiate the previous hypothesis that most lineages of Androcymbium in South Africa are much more ancient than their North African relatives, whose diversification began in the late Miocene-early
Pliocene.
Received July 25, 2001 Accepted December 6, 2001 相似文献
6.
Jane Carruthers 《Journal of the history of biology》2008,41(2):203-236
In recent decades conservation biology has achieved a high position among the sciences. This is certainly true of South Africa,
a small country, but the third most biodiverse in the world. This article traces some aspects of the transformation of South
African wildlife management during the 1930s to the 1960s from game reserves based on custodianship and the “balance of nature”
into scientifically managed national parks with a philosophy of “command and control” or “management by intervention.” In
1910 the four British colonies had formed the Union of South Africa, and by the 1920s there was wide acceptance of national
parks, a development influenced by their success in the United States. It was not, however, until after the Second World War,
that management of the expanding conservation estate altered from a rather unsystematic laissez faire variety, into more scientifically informed management practices with an efficient bureaucracy in charge. This was achieved
by modifications in organizational structures and institutional cultures initiated by a change of government in 1948 which,
this article argues, impacted in turn on wildlife management and shaped and professionalized many aspects of that field science.
“Management by intervention” was the hallmark of South African wildlife and conservation biology from the 1960s until recently,
when there have been shifts towards “adaptive resource management” in a period of further change in the country’s politics. 相似文献
7.
Michael H. Logan 《Human ecology: an interdisciplinary journal》2011,39(6):727-742
Interethnic marriage represents a major trend in the demographic history of American Indians. While the majority of these
unions involved Indian women and Caucasian men, a sizeable number occurred between Indians and African Americans. The children
of these bicultural marriages were “mixed bloods” who in turn typically married non-Indians or other mixed bloods. Using data
from the 1910 Census on American Indians in the United States and Alaska, this article explores why American Indians with
African ancestry enjoyed high fertility. Differential rates of fertility among American Indians in the past were due to a
number of underlying genetic, cultural, and environmental factors. By identifying these factors, the paradox of why Indian
women with African heritage did so well in terms of fertility largely disappears. African admixture, however, greatly complicates
Indian social identity. 相似文献
8.
Geographical affinities of the Cape flora, South Africa 总被引:1,自引:0,他引:1
Aim The flora characteristic of the Cape Floristic Region (CFR) is dominated by a relatively small number of clades that have been proposed as ‘Cape clades’. These clades have variously been suggested to have African or Austral affinities. Here we evaluate the support for these conflicting hypotheses. In addition, we test the hypothesis that these clades share a common time of differentiation from their geographical neighbours. Location The Cape Floristic Region, South Africa Methods We use both published and unpublished phylogenetic information to investigate the geographical sister areas of the Cape clades as well as the timing and the direction of biogeographical disjunctions. Results Almost half of the Cape clades for which unambiguous sister areas could be established show a trans‐Indian Ocean disjunction. The earliest trans‐Indian Ocean disjunction dates from 80 Ma. Other disjunctions date from various times in the Cenozoic, and we suggest that the process of recruiting lineages into the Cape flora might be ongoing. Relatively few Cape clades show a sister relationship with South America and tropical Africa, despite their relative geographical proximity. Numerous Cape clades contain species also found on tropical African mountains; in all cases tested, these species are shown to be embedded within the Cape clades. While many Cape clades show a relationship with the Eurasian temperate flora, this is complicated by their presence in tropical Africa. The single case study addressing this to date suggests that the Cape clade is nested within a European grade. Main conclusions Although many Cape clades show Austral rather than African relationships, there are numerous other patterns suggestive of a cosmopolitan flora. This spatial variation is echoed in the temporal data, from which, although there is wide variance around the dates of disjunctions, it is clear the Cape flora has been assembled over a long time period. There is no simple hypothesis that can account for the geographical sources of the currently distinctive Cape flora. The phylogenetic positions of Afromontane members of Cape clades suggest a history of dispersal from the CFR, rather than the reverse. 相似文献
9.
Convergence and contingency in production–precipitation relationships in North American and South African C4 grasslands 总被引:1,自引:0,他引:1
Mesic grasslands in North America and South Africa share many structural attributes, but less is known of their functional similarities. We assessed the control of a key ecosystem process, aboveground net primary production (ANPP), by interannual variation in precipitation amount and pattern via analysis of data sets (15- and 24-year periods) from long-term research programs on each continent. Both sites were dominated by C4 grasses and had similar growing season climates; thus, we expected convergence in precipitation–ANPP relationships. Lack of convergence, however, would support an alternative hypothesis—that differences in evolutionary history and purportedly greater climatic variability in South Africa fundamentally alter the functioning of southern versus northern hemisphere grasslands. Neither mean annual precipitation nor mean ANPP differed between the South African and North American sites (838 vs. 857 mm/year, 423.5 vs. 461.4 g/m2 respectively) and growing season precipitation–ANPP relationships were similar. Despite overall convergence, there were differences between sites in how the seasonal timing of precipitation affected ANPP. In particular, interannual variability in precipitation that fell during the first half of the growing season strongly affected annual ANPP in South Africa (P < 0.01), but was not related to ANPP in North America (P = 0.098). Both sites were affected similarly by late season precipitation. Divergence in the seasonal course of available soil moisture (chronically low in the winter and early spring in the South African site vs. high in the North American site) is proposed as a key contingent factor explaining differential sensitivity in ANPP to early season precipitation in these two grasslands. These long-term data sets provided no support for greater rainfall, temperature or ANPP variability in the South African versus the North American site. However, greater sensitivity of ANPP to early season precipitation in the South African grassland suggests that future patterns of productivity may be more responsive to seasonal changes in climate compared with the North American site. 相似文献
10.
Rowson, B., Tattersfield, P. & Symondson, W. O. C. (2010). Phylogeny and biogeography of tropical carnivorous land‐snails (Pulmonata: Streptaxoidea) with particular reference to East Africa and the Indian Ocean. —Zoologica Scripta, 40, 85–98. A phylogeny is presented for the speciose, near pan‐tropical, carnivorous achatinoid land‐snail superfamily Streptaxoidea inferred from DNA sequences (two nuclear and two mitochondrial regions) from 114 taxa from Africa, the Indian Ocean, Asia, South America and Europe. In all analyses, Streptaxidae are monophyletic, while the (two to six) previously recognised subfamilies are polyphyletic, as are several genus‐level taxa including the most speciose genus Gulella, necessitating major taxonomic review. The Asian Diapheridae are sister to Streptaxidae, which forms several well‐supported clades originating in a persistent basal polytomy. Divergence dating estimates, historical biogeography, and the fossil context suggest a Cretaceous origin of these families, but suggest Gondwanan vicariance predated most radiation. The basal polytomy dates to the Paleogene and may correspond to a rapid radiation in Africa. There is evidence for multiple Cenozoic dispersals followed by radiation, including at least two from Africa to South America, at least two from Africa to Asia and at least two from Africa to Madagascar, indicating Cenozoic turnover in tropical snail faunas. The endemic Seychelles and Mascarene streptaxid faunas each are composites of early Cenozoic lineages and more recent dispersals from Africa, with no direct evidence for an Asian origin as currently proposed. Peak streptaxid diversity in East Africa is explained by Neogene speciation among a large number of coexisting ancient lineages, a phenomenon most pronounced in the Eastern Arc‐Coastal Forests centre of endemism. This includes Miocene diversification in Gulella, a primarily East and South‐East African group which remains strikingly diverse even after unrelated ‘Gulella’ species are reclassified. 相似文献
11.
Mary Story June Stevens Marguerite Evans Carol E. Cornell Juhaeri Joel Gittelsohn Scott B. Going Theresa E. Clay David M. Murray 《Obesity (Silver Spring, Md.)》2001,9(6):356-363
Objective: This study examined dieting, weight perceptions, and self‐efficacy to eat healthy foods and engage in physical activity and their relationships to weight status and gender among American Indian elementary schoolchildren. Research Methods and Procedures: Data for this study were collected as part of the baseline examination for the Pathways study. Participants were 1441 second‐ through third‐grade American Indian children in 41 schools representing seven tribes in Arizona, New Mexico, and South Dakota who filled out a questionnaire and had heights and weights taken. Results: Forty‐two percent of the children were overweight or obese. No differences were found between overweight/obese and normal weight children for healthy food intentions or self‐efficacy. Heavier children (especially those with body mass index > 95th percentile) were more likely to have tried to lose weight or were currently trying to lose weight. No gender differences were found. Normal weight children chose a slightly heavier body size as most healthy compared with overweight/obese children. Discussion: The results indicate that children are concerned about their weight and that weight modification efforts are common among overweight American Indian children. School, community, and family‐based programs are needed to help young people adopt lifelong healthful eating and physical activity practices. 相似文献
12.
Gina Buijs 《Ethnic and racial studies》2013,36(4):661-682
The article examines ways in which the Lemba people of the Northern Province of South Africa have used their oral history and traditional customs associated with distant Semitic origins in Yemen, to claim a modern Jewish identity in racially divided South Africa. While Lemba live in Mozambique and Zimbabwe as well as in South Africa, it is only in the latter that belief in a Jewish origin is found. The article seeks to show that early white missionaries and colonial officials propagated a Semitic identity for the Lemba and in their writings emphasized the differences between the Lemba and their African neighbours through comparisons of Lemba customs with Jewish communities in Europe. Such writings contributed to an ethos of a distinct identity, through which, via the establishment of the Lemba Cultural Association, middle-class Lemba intellectuals sought to promote the Lemba. This was achieved in a situation where the apartheid regime in South Africa pursued a divide and rule policy which allowed the Bantustans to discriminate against ethnic minorities under their control. 相似文献
13.
Tore Strømme Marek R. Lipinski Paulus Kainge 《Reviews in Fish Biology and Fisheries》2016,26(2):235-248
Despite its economic and social importance for Namibia and South Africa, limited documented information exists regarding key aspects of the biology of deep-water hake, including its life cycle. This study utilizes data collected through the demersal surveys of the R/V Dr Fridtjof Nansen in South Africa and F/V Blue Sea 1 in Namibia to describe the migratory patterns of deep-water hake in space and time. Furthermore the study investigates aspects of the life cycle of this important species in the Benguela region. Results show that deep-water hake spawns between the western Agulhas Bank and Elands Bay in South Africa with the main nursery ground between Hondeklip Bay and the northern tip of Orange Banks. Deep-water hake in Namibia (up to the Kunene River) and along the south coast of South Africa (eastwards to Port Alfred) originate from these grounds, and undertake long-range migrations across latitudes and longitudes, respectively. This hypothesis is supported by the finding that spawning has not been observed in Namibia and there are no small juveniles along the South African south coast from the eastern border of the Agulhas Bank. The proposed pattern implies an interconnection between the Namibian and the South African components of the stock and the consequent need for a revision of the present management regime based on the assumption of stocks confined within the respective national jurisdictions. This study has used length frequency distributions in space and time in order to investigate the life cycle, in terms of origin, movement and population structure in particular, an approach that may also be useful for other widely distributed species. 相似文献
14.
The Grassland Biome is currently one of the most threatened biomes in South Africa and is in dire need of a biomonitoring protocol. The components of ecological integrity in these ecosystems are, however, too diverse and time-consuming to measure scrupulously. It is therefore necessary to develop a set of grassland indicators that are efficient and rapid in their assessment of grassland ecosystem integrity. The South African Grassland Scoring System (SAGraSS), based on the grassland insect community, is such a suggested indicator. The present study is the first to investigate the applicability and rapidity of this proposed method. Although SAGraSS scores correlated significantly with Ecological Index values (the most commonly used index by which veld condition is evaluated in central South Africa), the method proved to be tedious and the identification of insects taxing. We offer a number of changes to make the SAGraSS method a more rapid method of assessment. 相似文献
15.
《Endocrine practice》2012,18(5):668-675
ObjectiveTo determine whether the plasma level of sex hormone-binding globulin (SHBG) identifies South Asian Indian children at risk for metabolic syndrome.MethodsAdults and their children aged 5 to 9 years were recruited at the annual health fair at the Hindu temple serving the South Asian Indian community in Louisville, Kentucky. Anthropometric data were collected in adults and children, and blood pressure, lipid, and glucose levels were measured in adults. SHBG levels were measured in children using a fingerstick blood sample. In adults, metabolic syndrome was diagnosed according to the International Diabetes Federation criteria. Twelve months later, follow-up anthropometric data were obtained for a portion of the children.ResultsThe study included 30 sets of parents and 30 children. The prevalence of metabolic syndrome among 310 adults attending the health fair was 42% in men and 39% in women. Children with 1 parent with metabolic syndrome had 24% lower SHBG levels that increased to 55% of both parents had metabolic syndrome. SHBG levels were inversely related to waist circumference and to body mass index percentile. Both SHBG and waist circumference predicted weight gain over 1 year in children.ConclusionsLow SHBG levels were found in South Asian Indian children whose parents had attributes of metabolic syndrome. The dose dependency of SHBG is consistent with inheritance of a genetic trait, and if the results are applicable to other racial/ethnic groups, SHBG may be a useful marker to identify at-risk children for early intervention. (Endocr Pract. 2012;18:668-675) 相似文献
16.
Lynnath E. Beckley Geremy Cliff Malcolm J. Smale Leonard J.V. Compagno 《Environmental Biology of Fishes》1997,50(3):343-348
Available information on whale shark strandings around the coast of South Africa during the period 1984–1995 was collated.
Stranded animals ranged in size from 3–11 m TL, most were immature and the sex ratio was even. Aerial observations and sightings
by divers indicate that whale sharks are most abundant in South African waters during the austral summer and autumn months.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Mike Murray 《PloS one》2016,11(4)
AbstractWealthy schools appoint better qualified teachers, less wealthy schools under qualified teachers. Added to this mix is a powerful teacher’s union whose policies attempt to entrench the job security of teachers in the less wealthy schools irrespective of whether they can teach their subjects or not. Can one isolate these effects from that of other socio-demographic factors that may also be affecting the performance of students when they enrol for a degree at the University of KwaZulu-Natal (UKZN)? An outcome variable that subtracts the number of courses that have been failed from the number of courses that have been passed, dividing this by the total number of years that they have spent studying for a particular degree will be used as a response variable for this paper.ObjectivesThe system of secondary education in South Africa is highly polarized. On the one hand, we have a group of mainly Black African students, forming about 80% of the total student population, that come from a vastly under-resourced rural or township based community. On the other hand, we have a group of predominantly White and Indian students who are able to attend a far better resourced set of private schools. Added to this mix, we have 240,000 of South Africa’s total number of 390,000 primary and secondary school teachers who belong to a powerful teacher’s union which enjoys a strong political alliance with the ruling party in South Africa. With most of their union members teaching in the less wealthy schools in South Africa, `school background’ now includes a politically motivated component that focuses on teacher self–interest rather than the education of the child. What sort of effect does school background have on the performance of students when they enter an institution of higher learning? More importantly, can one isolate the effect of school background from that of other possibly confounding factors such as gender, financial aid and the receipt of some form of residence based accommodation that will also impact on their performance while at university?MethodA total of 6,183 students enrolling for a degree at the University of KwaZulu-Natal (UKZN) over the period 2008 to 2012 were used a dataset for this study. Permission to use this dataset was given by the Teaching and Learning Office at UKZN. The database that was used for this study was obtained from the Division of Management Information (DMI) office at UKZN. The percentage based marks that students have managed to record for Mathematics, English, Biology and Accounting in their school leaving exams together with some other important but observable socio-economic factors were included in a regression model to determine how students will perform at UKZN. Socio-economic variables relating to gender, race and whether they have receivd some form of financial aid or residence based accommodation while studying at university were also included as predictor variables in our regression based model structure.
Results and Conclusions
An interaction effect associated with being a Black African student who has been privileged enough to attend a quintile five school was found to be significant. A main effect associated with being able to attend a more privileged quintile 5 school however was found to be nonsignificant even after an adjustment has been made for gender, race, the receipt of some form of financial aid and residence based accommodation. Given that UKZN already has a number of bridging programs in place that target students who have come from a less privileged background, for university based policymakers, this result may help to justify the targeted selection of Black African students from the less privileged schools that is taking place. Because some of the disparity in matric performance that we are observing may also be associated with teacher competency and the protective influence of a powerful teacher’s union, this paper may also help to highlight some of the economic costs related with having under-prepared students. “A mind is a terrible thing to waste”–United Negro College Fund. 相似文献18.
Exenberger S 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2003,61(2):233-243
The present research examined the influence of the two independent variables sex and race on the choice of friends in pre-school children. Data for this investigation were collected in two pre-schools, one situated in Stellenbosch, South Africa, the other in London, U.K. Both schools have in common that they accommodate children of different racial backgrounds (black, white, and coloured children), but the children's experience with desegregated classrooms differ. Friendship was operational defined with thirteen categories, summarized to the basic category pro-social behaviour. Fifty hours of free-play time were taped with one video camera in South Africa, and hundred hours were taped with two video cameras in London. The results showed that sex and race interact in their effect on the choice of friends. In South Africa race is supposed to be a strong indicator for friendship choices, especially for black children, whereas the black children in London choose friends more or less on the basis of sex. 相似文献
19.
20.
Benjamin W. Price David C. Marshall Nigel P. Barker Chris Simon Martin H. Villet 《Systematic Entomology》2019,44(4):842-861
The Platypleurini is a large group of charismatic cicadas distributed from Cape Agulhas in South Africa, through tropical Africa, Madagascar, India and eastern Asia to Japan, with generic diversity concentrated in equatorial and southern Africa. This distribution suggests the possibility of a Gondwanan origin and dispersal to eastern Asia from Africa or India. We used a four‐gene (three mitochondrial) molecular dataset, fossil calibrations and molecular clock information to explore the phylogenetic relationships of the platypleurine cicadas and the timing and geography of their diversification. The earliest splits in the tribe were found to separate forest genera in Madagascar and equatorial Africa from the main radiation, and all of the Asian/Indian species sampled formed a younger clade nested well within the African taxa. The tribe appears to have diversified during the Cenozoic, beginning c. 50–32 Ma, with most extant African lineages originating in the Miocene or later, well after the breakup of the Gondwanan landmass. Biogeographical analysis suggests an African origin for the tribe and a single dispersal event founding the Asian platypleurines, although additional taxon sampling and genetic data will be needed to confirm this pattern because key nodes in the tree are still weakly supported. Two Platypleurini genera from Madagascar (Pycna Amyot & Audinet‐Serville, Yanga Distant) are found to have originated by late Miocene dispersal of a single lineage from Africa. The genus Platypleura is recovered as polyphyletic, with Platypleura signifera Walker from South Africa and many Asian/Indian species apparently requiring assignment to different genera, and a new Platypleura concept is proposed with the synonymization of Azanicada Villet syn.n. The genera Orapa Distant and Hamza Distant, currently listed within separate tribes but suspected of platypleurine affinity, are nested deeply within the Platypleurini radiation. The tribe Orapini syn.n . is here synonymized while the tribe Hamzini is pending a decision of the ICZN to preserve nomenclatorial stability. 相似文献