190 research outputs found

    La colección de primates del Museo de Ciencias Naturales de Barcelona (España)

    Get PDF
    L'MCNB conserva un total de 309 exemplars de primats no humans. La col·lecció consta de 102 exemplars dissecats, 33 pells, 73 esquelets, 24 esquelets postcranials, vuit esquelets muntats, 54 cranis, tres animals sencers en alcohol i 31 mostres d'altres tipus (ossos o altres). Els darrers anys s'ha portat a terme una revisió completa i una reorganització de la col·lecció. Amb 39 gèneres, aquesta inclou una àmplia gamma de primats no humans. Conté mostres d'Àfrica, Àsia i Amèrica del Sud i Central, el 10,26% són estrepsirins, el 26,92% micos del Nou Món i el 62,18% micos del Vell Món. El Museu conserva algunes espècies en perill d'extinció o rares. En aquest treball es presenten els resultats de la revisió taxonòmica amb resultats actualitzats de les determinacions portades a terme, amb una llista completa de les mostres que inclou informació sobre l'edat, la classe i el tipus de mostra. Paraules clau: col·lecció de Ciències Naturals, primats, revisió.The Natural Science Museum of Barcelona (MCNB) houses a total of 309 specimens of non–human primates. The collection comprises 102 stuffed animals, 33 skins, 73 skeletons, 24 postcranial skeletons, eight mounted skeletons, 54 skulls, three whole animals in alcohol, and 31 other samples (bones and other). Over the last two years the collection has been completely reviewed and reorganized. The collection contains 39 genera and includes a wide range of extant non–human primates. It houses specimens from Africa, Asia and South and Central America, with 10.26% of samples being Strepsirrhines, 26.92% New World monkeys and 62.18% Old World monkeys. The Museum houses some endangered or rare species. In this work we present the contents of the recent review with new and pdated taxonomic attributions together with a complete list of samples that includes information on age, class and preservation status for each specimen. Key words: naturalistic collection, primates, review.El MCNB conserva un total de 309 ejemplares de primates no humanos. La colección consta de 102 ejemplares disecados, 33 pieles, 73 esqueletos, 24 esqueletos postcraneales, ocho esqueletos montados, 54 cráneos, tres animales enteros en alcohol, y 31 muestras de otro tipo (huesos y otros). En los últimos dos años se ha llevado a cabo una revisión completa y una reorganización de la colección. Con 39 géneros, la colección incluye una amplia gama de primates no humanos. Contiene muestras de África, Asia y América del Sur y Central, el 10,26% son estrepsirrinos, el 26,92% monos del Nuevo Mundo y el 62,18% del Viejo Mundo. El Museo alberga algunas especies en peligro de extinción o raras. En este trabajo se presentan los resultados de la revisión taxonómica con resultados actualizados de las determinaciones llevadas a cabo, con una lista completa de las muestras incluyendo información sobre la edad, la clase y el tipo de muestra. Palabras clave: colección de Ciencias Naturales, primates, revisión

    Critical fluctuations and random-anisotropy glass transition in nematic elastomers

    Full text link
    We carry out a detailed deuterium NMR study of local nematic ordering in polydomain nematic elastomers. This system has a close analogy to the random-anisotropy spin glass. We find that, in spite of the quadrupolar nematic symmetry in 3-dimensions requiring a first-order transition, the order parameter in the quenched ``nematic glass'' emerges via a continuous phase transition. In addition, by a careful analysis of the NMR line shape, we deduce that the local director fluctuations grow in a critical manner around the transition point. This could be the experimental evidence for the Aizenman-Wehr theorem about the quenched impurities changing the order of discontinuous transition

    Heptacarbonyl-1κ3 C,2κ4 C-(4-phenyl­pyridine-1κN)di-μ-phenyltellurido-1:2κ4 Te:Te-dirhenium(I)

    Get PDF
    In the title complex, [Re2(C6H5Te)2(C11H9N)(CO)7], two Re atoms are coordinated in slightly distorted octa­hedral coordination environments and are bridged by two Te atoms, which are coordinated in trigonal-pyramidal environments. The torsion angle for the Te—Re—Te—Re sequence of atoms is 17.06 (3)°. The crystal structure is stabilized by weak C—H⋯O and C—H⋯π inter­actions. In addition, there are Te⋯Te distances [4.0392 (12) Å] and O⋯O distances [2.902 (19) Å] which are shorter than the sum of the van der Waals radii for these atoms. A short inter­molecular lone pair⋯π distance [C O⋯Cg = 3.31 (2) Å] is also observed

    Predictors of orbital convergence in primates: A test of the snake detection hypothesis of primate evolution

    Get PDF
    Traditional explanations for the evolution of high orbital convergence and stereoscopic vision in primates have focused on how stereopsis might have aided early primates in foraging or locomoting in an arboreal environment. It has recently been suggested that predation risk by constricting snakes was the selective force that favored the evolution of orbital convergence in early primates, and that later exposure to venomous snakes favored further degrees of convergence in anthropoid primates. Our study tests this snake detection hypothesis (SDH) by examining whether orbital convergence among extant primates is indeed associated with the shared evolutionary history with snakes or the risk that snakes pose for a given species. We predicted that orbital convergence would be higher in species that: 1) have a longer history of sympatry with venomous snakes, 2) are likely to encounter snakes more frequently, 3) are less able to detect or deter snakes due to group size effects, and 4) are more likely to be preyed upon by snakes. Results based on phylogenetically independent contrasts do not support the SDH. Orbital convergence shows no relationship to the shared history with venomous snakes, likelihood of encountering snakes, or group size. Moreover, those species less likely to be targeted as prey by snakes show significantly higher values of orbital convergence. Although an improved ability to detect camouflaged snakes, along with other cryptic stimuli, is likely a consequence of increased orbital convergence, this was unlikely to have been the primary selective force favoring the evolution of stereoscopic vision in primates

    New insights into the distribution and conservation status of the Golden-White Tassel-Ear Marmoset Mico chrysoleucos (Primates, Callitrichidae)

    Get PDF
    Among the 13 Mico species recognized by the IUCN Red List of Threatened Species, six are listed as "Data Deficient". The geographic range of most of the Mico species has been estimated from only a few records. We report new localities and the geographic extension of Mico chrysoleucos. In addition, we confirmed the presence of the species in two distinct protected areas. We modeled the habitat suitability of M. chrysoleucos using the maximum entropy method and including new records obtained by the authors in the state of Amazonas, Brazil. From the total area of occurrence calculated for the species, 22.8% is covered by protected areas and indigenous lands. The annual mean deforestation rate estimated between 2000 and 2015 was 2.95%, and the total area deforested by 2015 was 3354 km2 or 8.6% of the total distribution limits of the species. The habitat lost between 2000 and 2015 was 3.2% (1131 km2 ) of the total potential distribution, while the habitat loss area legally protected was 31 km2, and the habitat loss in settlements was equal to 691 km2. Our results extend the geographic distribution of the species about 100 km farther south, with the Maracanã River being a possible geographic barrier for the species. The significantly low rate of habitat loss inside protected areas and indigenous land, when compared to unprotected areas, points out the importance of these areas to M. chrysoleucos conservation. The species is relatively wide-ranging, legally protected, and resilient to regional anthropic threats. However, the hydroelectric schemes and the improvement of the road system in southern Amazonia pose an imminent threat to the species

    Phosphoprotein Associated with Glycosphingolipid-Enriched Microdomains Differentially Modulates Src Kinase Activity in Brain Maturation

    Get PDF
    Src family kinases (SFK) control multiple processes during brain development and function. We show here that the phosphoprotein associated with glycosphigolipid-enriched microdomains (PAG)/Csk binding protein (Cbp) modulates SFK activity in the brain. The timing and localization of PAG expression overlap with Fyn and Src, both of which we find associated to PAG. We demonstrate in newborn (P1) mice that PAG negatively regulates Src family kinases (SFK). P1 Pag1-/- mouse brains show decreased recruitment of Csk into lipid rafts, reduced phosphorylation of the inhibitory tyrosines within SFKs, and an increase in SFK activity of >/ = 50%. While in brain of P1 mice, PAG and Csk are highly and ubiquitously expressed, little Csk is found in adult brain suggesting altered modes of SFK regulation. In adult brain Pag1-deficiency has no effect upon Csk-distribution or inhibitory tyrosine phosphorylation, but kinase activity is now reduced (−20–30%), pointing to the development of a compensatory mechanism that may involve PSD93. The distribution of the Csk-homologous kinase CHK is not altered. Importantly, since the activities of Fyn and Src are decreased in adult Pag1-/- mice, thus presenting the reversed phenotype of P1, this provides the first in vivo evidence for a Csk-independent positive regulatory function for PAG in the brain

    The evolution of pair-living, sexual monogamy, and cooperative infant care: Insights from research on wild owl monkeys, titis, sakis, and tamarins

    Get PDF
    “Monogamy” and pair bonding have long been of interest to anthropologists and primatologists. Their study contributes to our knowledge of human evolutionary biology and social evolution without the cultural trappings associated with studying human societies directly. Here, we first provide an overview of theoretical considerations, followed by an evaluation of recent comparative studies of the evolution of “social monogamy”; we are left with serious doubts about the conclusions of these studies that stem from the often poor quality of the data used and an overreliance on secondary sources without vetting the data therein. We then describe our field research program on four “monogamous” platyrrhines (owl monkeys, titis, sakis, and tamarins), evaluate how well our data support various hypotheses proposed to explain “monogamy,” and compare our data to those reported on the same genera in comparative studies. Overall, we found a distressing lack of agreement between the data used in comparative studies and data from the literature for the taxa that we work with. In the final section, we propose areas of research that deserve more attention. We stress the need for more high‐quality natural history data, and we urge researchers to be cautious about the uncritical use of variables of uncertain internal validity. Overall, it is imperative that biological anthropologists establish and follow clear criteria for comparing and combining results from published studies and that researchers, reviewers, and editors alike comply with these standards to improve the transparency, reproducibility, and interpretability of causal inferences made in comparative studies.Division of Behavioral and Cognitive Sciences; National Institute of Child Health and Human Development; National Institutes of Agin

    Collective cell migration and metastases induced by an epithelial-to-mesenchymal transition in Drosophila intestinal tumors.

    Get PDF
    Metastasis underlies the majority of cancer-related deaths yet remains poorly understood due, in part, to the lack of models in vivo. Here we show that expression of the EMT master inducer Snail in primary adult Drosophila intestinal tumors leads to the dissemination of tumor cells and formation of macrometastases. Snail drives an EMT in tumor cells, which, although retaining some epithelial markers, subsequently break through the basal lamina of the midgut, undergo a collective migration and seed polyclonal metastases. While metastases re-epithelialize over time, we found that early metastases are remarkably mesenchymal, discarding the requirement for a mesenchymal-to-epithelial transition for early stages of metastatic growth. Our results demonstrate the formation of metastases in adult flies, and identify a key role for partial-EMTs in driving it. This model opens the door to investigate the basic mechanisms underlying metastasis, in a powerful in vivo system suited for rapid genetic and drug screens

    Non-Human primates in the work of Ulisse Aldrovandi (1522-1605)

    Full text link

    Non-Human primates in the work of Ulisse Aldrovandi (1522-1605)

    No full text
    corecore