58 research outputs found
First GIS analysis of modern stone tools used by wild chimpanzees (Pan troglodytes verus) in Bossou, Guinea, West Africa
Stone tool use by wild chimpanzees of West Africa offers a unique opportunity to explore the evolutionary roots of technology during human evolution. However, detailed analyses of chimpanzee stone artifacts are still lacking, thus precluding a comparison with the earliest archaeological record. This paper presents the first systematic study of stone tools used by wild chimpanzees to crack open nuts in Bossou (Guinea-Conakry), and applies pioneering analytical techniques to such artifacts. Automatic morphometric GIS classification enabled to create maps of use wear over the stone tools (anvils, hammers, and hammers/anvils), which were blind tested with GIS spatial analysis of damage patterns identified visually. Our analysis shows that chimpanzee stone tool use wear can be systematized and specific damage patterns discerned, allowing to discriminate between active and passive pounders in lithic assemblages. In summary, our results demonstrate the heuristic potential of combined suites of GIS techniques for the analysis of battered artifacts, and have enabled creating a referential framework of analysis in which wild chimpanzee battered tools can for the first time be directly compared to the early archaeological record.Leverhulme Trust [IN-052]; MEXT [20002001, 24000001]; JSPS-U04-PWS; FCT-Portugal [SFRH/BD/36169/2007]; Wenner-Gren Foundation for Anthropological Researc
Cumulative culture in nonhumans : overlooked findings from Japanese monkeys?
The authors thank Corpus Christi College (Cambridge) for funding DS’s visit to Koshima and Prof. Tetsuro Matsuzawa for funding WCM’s visit to Koshima.Cumulative culture, generally known as the increasing complexity or efficiency of cultural behaviors additively transmitted over successive generations, has been emphasized as a hallmark of human evolution. Recently, reviews of candidates for cumulative culture in nonhuman species have claimed that only humans have cumulative culture. Here, we aim to scrutinize this claim, using current criteria for cumulative culture to re-evaluate overlooked qualitative but longitudinal data from a nonhuman primate, the Japanese monkey (Macaca fuscata). We review over 60 years of Japanese ethnography of Koshima monkeys, which indicate that food-washing behaviors (e.g., of sweet potato tubers and wheat grains) seem to have increased in complexity and efficiency over time. Our reassessment of the Koshima ethnography is preliminary and nonquantitative, but it raises the possibility that cumulative culture, at least in a simple form, occurs spontaneously and adaptively in other primates and nonhumans in nature.Publisher PDFPeer reviewe
Sex Bias and Social Influences on Savanna Chimpanzee (Pan troglodytes verus) Nest Building Behavior
Many primates show sex differences in behavior, particularly social behavior, but also tool use for extractive foraging. All great apes learn to build a supportive structure for sleep. Whether sex differences exist in building, as in extractive foraging, is unknown, and little is known about how building skills develop and vary between individuals in the wild. We therefore aimed to describe the nesting behavior of savanna chimpanzees (Pan troglodytes verus) in Fongoli, Senegal, to provide comparative data and to investigate possible sex or age differences in nest building behaviors and nest characteristics. We followed chimpanzee groups to their night nesting sites to record group (55 nights) and individual level data (17 individuals) on nest building initiation and duration (57 nests) during the dry season between October 2007 and March 2008. We returned the following morning to record nest and tree characteristics (71 nests built by 25 individuals). Fongoli chimpanzees nested later than reported for other great apes, but no sex differences in initiating building emerged. Observations were limited but suggest adult females and immature males to nest higher, in larger trees than adult males, and adult females to take longer to build than either adult or immature males. Smaller females and immature males may avoid predation or access thinner, malleable branches, by nesting higher than adult males. These differences suggest that sex differences described for chimpanzee tool use may extend to nest-building, with females investing more time and effort in constructing a safe, warm structure for sleep than males do
Neutrinos
229 pages229 pages229 pagesThe Proceedings of the 2011 workshop on Fundamental Physics at the Intensity Frontier. Science opportunities at the intensity frontier are identified and described in the areas of heavy quarks, charged leptons, neutrinos, proton decay, new light weakly-coupled particles, and nucleons, nuclei, and atoms
Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC
DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6 × 6 × 6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties
Evidence for avian cell autonomous sex identity (CASI) and implications for the sex-determination process?
The antecedents and outcomes of creative cognition
This chapter summarises the antecedents and outcomes that are associated with creative potential and creative achievement, as well as the outcomes of creative practice and engagement with the arts. It provides a concise overview of the relationships between creativity and individual or dispositional factors such as intelligence, personality and executive functions, while also exploring the effects of environmental or situational factors, such as reward and evaluation, on creativity and motivation with an especial focus on two important outcomes of creative cognition, academic achievement and wellbeing. The consequences associated with engagement in creative practice and arts-integrated teaching are also discussed
Editing the genome of chicken primordial germ cells to introduce alleles and study gene function
With continuing advances in genome sequencing technology, the chicken genome
assembly is now better annotated with improved accuracy to the level of single
nucleotide polymorphisms. Additionally, the genomes of other birds such as the duck,
turkey and zebra finch have now been sequenced. A great opportunity exists in avian
biology to use genome editing technology to introduce small and defined sequence
changes to create specific haplotypes in chicken to investigate gene regulatory
function, and also perform rapid and seamless transfer of specific alleles between
chicken breeds. The methods for performing such precise genome editing are well
established for mammalian species but are not readily applicable in birds due to
evolutionary differences in reproductive biology.
A significant leap forward to address this challenge in avian biology was the
development of long-term culture methods for chicken primordial germ cells (PGCs).
PGCs present a cell line in which to perform targeted genetic manipulations that will
be heritable. Chicken PGCs have been successfully targeted to generate genetically
modified chickens. However, genome editing to introduce small and defined sequence
changes has not been demonstrated in any avian species. To address this deficit, the
application of CRISPR/Cas9 and short oligonucleotide donors in chicken PGCs for
performing small and defined sequence changes was investigated in this thesis.
Specifically, homology-directed DNA repair (HDR) using oligonucleotide donors
along with wild-type CRISPR/Cas9 (SpCas9-WT) or high fidelity CRISPR/Cas9
(SpCas9-HF1) was investigated in cultured chicken PGCs. The results obtained
showed that small sequences changes ranging from a single to a few nucleotides could
be precisely edited in many loci in chicken PGCs. In comparison to SpCas9-WT,
SpCas9-HF1 increased the frequency of biallelic and single allele editing to generate
specific homozygous and heterozygous genotypes. This finding demonstrates the
utility of high fidelity CRISPR/Cas9 variants for performing sequence editing with
high efficiency in PGCs.
Since PGCs can be converted into pluripotent stem cells that can potentially
differentiate into many cell types from the three germ layers, genome editing of PGCs
can, therefore, be used to generate PGC-derived avian cell types with defined genetic
alterations to investigate the host-pathogen interactions of infectious avian diseases.
To investigate this possibility, the chicken ANP32A gene was investigated as a target
for genetic resistance to avian influenza virus in PGC-derived chicken cell lines.
Targeted modification of ANP32A was performed to generate clonal lines of genome-edited
PGCs. Avian influenza minigenome replication assays were subsequently
performed in the ANP32A-mutant PGC-derived cell lines. The results verified that
ANP32A function is crucial for the function of both avian virus polymerase and
human-adapted virus polymerase in chicken cells. Importantly, an asparagine to
isoleucine mutation at position 129 (N129I) in chicken ANP32A failed to support
avian influenza polymerase function. This genetic change can be introduced into
chickens and validated in virological studies. Importantly, the results of my
investigation demonstrate the potential to use genome editing of PGCs as an approach
to generate many types of unique cell models for the study of avian biology.
Genome editing of PGCs may also be applied to unravel the genes that control the
development of the avian germ cell lineage. In the mouse, gene targeting has been
extensively applied to generate loss-of-function mouse models to use the reverse
genetics approach to identify key genes that regulate the migration of specified PGCs
to the genital ridges. Avian PGCs express similar cytokine receptors as their
mammalian counterparts. However, the factors guiding the migration of avian PGCs
are largely unknown. To address this, CRISPR/Cas9 was used in this thesis to generate
clonal lines of chicken PGCs with loss-of-function deletions in the CXCR4 and c-Kit
genes which have been implicated in controlling mouse PGC migration. The results
showed that CXCR4-deficient PGCs are absent from the gonads whereas c-Kit-deficient
PGCs colonise the developing gonads in reduced numbers and are
significantly reduced or absent from older stages. This finding shows a conserved role
for CXCR4 and c-Kit signalling in chicken PGC development. Importantly, other
genes suspected to be involved in controlling the development of avian germ cells can
be investigated using this approach to increase our understanding of avian reproductive
biology.
Finally, the methods developed in this thesis for editing of the chicken genome may
be applied in other avian species once culture methods for the PGCs from these species
are develope
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