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Joseph V. Ferraro Thomas W. Plummer Briana L. Pobiner James S. Oliver Laura C. Bishop David R. Braun Peter W. Ditchfield John W. Seaman III Katie M. Binetti John W. Seaman Jr Fritz Hertel Richard Potts 《PloS one》2013,8(4)
The emergence of lithic technology by ∼2.6 million years ago (Ma) is often interpreted as a correlate of increasingly recurrent hominin acquisition and consumption of animal remains. Associated faunal evidence, however, is poorly preserved prior to ∼1.8 Ma, limiting our understanding of early archaeological (Oldowan) hominin carnivory. Here, we detail three large well-preserved zooarchaeological assemblages from Kanjera South, Kenya. The assemblages date to ∼2.0 Ma, pre-dating all previously published archaeofaunas of appreciable size. At Kanjera, there is clear evidence that Oldowan hominins acquired and processed numerous, relatively complete, small ungulate carcasses. Moreover, they had at least occasional access to the fleshed remains of larger, wildebeest-sized animals. The overall record of hominin activities is consistent through the stratified sequence – spanning hundreds to thousands of years – and provides the earliest archaeological evidence of sustained hominin involvement with fleshed animal remains (i.e., persistent carnivory), a foraging adaptation central to many models of hominin evolution. 相似文献
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Roberts P Weston S Wild B Boston C Ditchfield P Shortland AJ Pollard AM 《American journal of physical anthropology》2012,147(1):1-10
The Guizhou snub‐nosed monkey (Rhinopithecus brelichi) is a primate species endemic to the Wuling Mountains in southern China. With a maximum of 800 wild animals, the species is endangered and one of the rarest Chinese primates. To assess the genetic diversity within R. brelichi and to analyze its genetic population structure, we collected fecal samples from the wild R. brelichi population and sequenced the hypervariable region I of the mitochondrial control region from 141 individuals. We compared our data with those from the two other Chinese snub‐nosed species (R. roxellana, R. bieti) and reconstructed their phylogenetic relationships and divergence times. With only five haplotypes and a maximum of 25 polymorphic sites, R. brelichi shows the lowest genetic diversity in terms of haplotype diversity (h), nucleotide diversity (π), and average number of pairwise nucleotide differences (Π). The most recent common ancestor of R. brelichi lived ~0.36 million years ago (Ma), thus more recently than those of R. roxellana (~0.91 Ma) and R. bieti (~1.33 Ma). Phylogenetic analysis and analysis of molecular variance revealed a clear and significant differentiation among the three Chinese snub‐nosed monkey species. Population genetic analyses (Tajima's D, Fu's Fs, and mismatch distribution) suggest a stable population size for R. brelichi. For the other two species, results point in the same direction, but population substructure possibly introduces some ambiguity. Because of the lower genetic variation, the smaller population size and the more restricted distribution, R. brelichi might be more vulnerable to environmental changes or climate oscillations than the other two Chinese snub‐nosed monkey species. Am J Phys Anthropol, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
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Monik Oprea Poliana Mendes Thiago B. Vieira Albert D. Ditchfield 《Biodiversity and Conservation》2009,18(9):2361-2371
The effects of urbanization on bats are poorly understood, but published data suggests it might be detrimental to them. Even
though urban parks provide refuge to native biota, the nature of the urban landscape exacerbates the insularization process.
In order to evaluate if wooded streets in an urban landscape provide connectivity for bats, we compared bat community structure
in three different types of habitats: urban parks, wooded streets and non-wooded streets. Sampling occurred monthly from August
2006 to July 2007 in the city of Vitória, southeastern Brazil. Richness, relative abundance and diversity were higher in urban
parks and lower in non-wooded streets. Jaccard’s similarity index showed that the wooded streets are more similar to non-wooded
streets than to urban parks. Urbanization may benefit generalist species by providing new resources, but for specialist species
critical resources may be lost and persistence endangered. There is evidence that wooded streets may provide some degree of
connectivity for birds in urban landscapes, but our results suggest that this is not the case, with wooded streets being used
by few individuals of a few species. Vegetation cover is important to maintain bat diversity in urban centers. Activities
like landscape planning and gardening should include biodiversity data in their outputs in order to better design a landscape
that improves the likelihood of persistence of bats. 相似文献
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Redondo RA Brina LP Silva RF Ditchfield AD Santos FR 《Molecular phylogenetics and evolution》2008,49(1):44-58
A molecular phylogeny of the genus Artibeus using 19 of the 20 recognized species, many with samples from a broad geographic range, is presented. The analysis shows a clear distinction between the two subgenera (or genera), the 'large'Artibeus and the 'small'Dermanura, in both mitochondrial and nuclear genes. The placement and status of A. concolor remains inconclusive and is presented as the third subgenus Koopmania. The phylogenies and divergence time estimates show a marked influence of the Andes in the formation of the subgenera and the main lineages inside each subgenus. Nuclear genes showed a highly incomplete lineage sorting among species inside subgenera Artibeus and Dermanura. Indeed, shared alleles were also found between Artibeus and Koopmania, which are presumed to have split apart during the Miocene, showing that great care should be taken in using these markers. Cytochrome-b gene divergences and monophyly analyses suggest that A. lituratus and A. intermedius are indeed conspecifics. These analyses also suggested the existence of at least four 'new' species revealing a significant cryptic diversity inside the genus. 相似文献
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Frost SR Plummer T Bishop LC Ditchfield P Ferraro J Hicks J 《American journal of physical anthropology》2003,122(3):191-199
The Rawi Gully, located on the Homa Peninsula in southwestern Kenya, has produced several fossil elements of a large cercopithecid from sediments approximately 2.5 million years old (Ma). Nearly all of these elements appear to represent a single adult male individual of the colobine species Cercopithecoides kimeui Leakey, 1982. Part of the face, mandible, dentition, and several small postcranial fragments were collected by the Homa Peninsula Paleoanthropological Project (HPPP) in 1994 and 1995. This individual also appears to be represented by material collected in two previous expeditions to the site, one led by David Pilbeam in the 1970s and an earlier expedition led by L.S.B. Leakey in 1933. This specimen may extend the first appearance of C. kimeui by approximately 500 Kyr, and provides the first evidence for much of the male facial morphology in this species. Furthermore, Rawi may represent a more wooded habitat than the other occurrences of C. kimeui at Olduvai Gorge, Tanzania, and Koobi Fora, Kenya, indicating that C. kimeui may have been relatively flexible in its habitat preferences. 相似文献
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BACKGROUND: This study investigated causes of malaria and how cases were managed at household level, in order to improve the ability to identify malaria and ensure correct use of chloroquine. It was conducted in Nakonde District, Northern Province of Zambia, between 2000 and 2001. Nakonde district is in a hyperendemic malaria province, where Plasmodium falciparum is predominant. The district has a total population of 153, 548 people, the majority of whom are peasant farmers. The main aim of the post intervention survey was to establish the proportion of caretakers of children five years and below, who were able to identify simple and severe malaria and treat it correctly using chloroquine in the home. METHODS: A baseline survey was conducted in five wards divided into intervention and control.Intervention and control wards were compared. Village health motivators and vendors were identified and trained in three intervention wards, as a channel through which information on correct chloroquine dose could be transmitted. A total of 575 carers, who were 15 years old and above and had a child who had suffered from malaria 14 days before the survey commenced, were interviewed. The two control wards received no intervention. 345 caretakers were from the intervention wards, while 230 came from the control wards. Identification of malaria and correct use of anti-malarial drugs was assessed in terms of household diagnosis of malaria in children under five years, type and dose of anti-malarial drugs used, self medication and the source of these anti-malarials. RESULTS: The majority of respondents in the study were females (81%). Chloroquine was the most frequently used anti-malarial (48.5%) in both the intervention and control wards. There was no difference between the intervention and control wards at pre-intervention (P = 0.266 and P = 0.956), in the way mothers and other caretakers identified simple and severe malaria. At baseline, knowledge on correct chloroquine dosage in the under five children was comparable between intervention and control wards. Post-intervention revealed that mothers and other caretakers were 32% and 51%, respectively, more likely to identify simple and severe malaria. There was a 60% increase on correct chloroquine dosage in all age groups among carers living in post-intervention wards. CONCLUSION: Compliance with standard therapeutic doses and correct identification of malaria was poorest in control wards, where no motivators and vendors were trained. 相似文献
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SE?Aleshin AV?Timofeev MV?Khoretonenko LG?Zakharova GV?Pashvykina JR?Stephenson AM?Shneider AD?AltsteinEmail author 《BMC microbiology》2005,5(1):45
Background
Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV) and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE) virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol. 相似文献40.