131 research outputs found

    La faune en Région predésertique dans le Nord de l’Afrique. Facteurs de dégradation, moyens de sauvegarde

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    Recherches sur le rôle éventuel de Lumbricus terrestris dans la transmission expérimentale du virus de la fièvre aphteuse

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    Dhennin Léone, Heim de Balsac Henri, Verge Jean, Dhennin Louis. Recherches sur le rôle éventuel de Lumbricus terrestris dans la transmission expérimentale de la fièvre aphteuse. In: Bulletin de l'Académie Vétérinaire de France tome 116 n°4, 1963. pp. 153-155

    Genetic admixture despite ecological segregation in a North African sparrow hybrid zone (Aves, Passeriformes, Passer domesticus × Passer hispaniolensis)

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    Under different environmental conditions, hybridization between the same species might result in different patterns of genetic admixture. Particularly, species pairs with large distribution ranges and long evolutionary history may have experienced several independent hybridization events over time in different zones of overlap. In birds, the diverse hybrid populations of the house sparrow (Passer domesticus) and the Spanish sparrow (Passer hispaniolensis) provide a striking example. Throughout their range of sympatry, these two species do not regularly interbreed; however, a stabilized hybrid form (Passer italiae) exists on the Italian Peninsula and on several Mediterranean is‐ lands. The spatial distribution pattern on the Eurasian continent strongly contrasts the situation in North Africa, where house sparrows and Spanish sparrows occur in close vicinity of phenotypically intermediate populations across a broad mosaic hy‐ brid zone. In this study, we investigate patterns of divergence and admixture among the two parental species, stabilized and nonstabilized hybrid populations in Italy and Algeria based on a mitochondrial marker, a sex chromosomal marker, and 12 micros‐ atellite loci. In Algeria, despite strong spatial and temporal separation of urban early‐ breeding house sparrows and hybrids and rural late‐breeding Spanish sparrows, we found strong genetic admixture of mitochondrial and nuclear markers across all study populations and phenotypes. That pattern of admixture in the North African hybrid zone is strikingly different from i) the Iberian area of sympatry where we observed only weak asymmetrical introgression of Spanish sparrow nuclear alleles into local house sparrow populations and ii) the very homogenous Italian sparrow population where the mitogenome of one parent (P. domesticus) and the Z‐chromosomal marker of the other parent (P. hispaniolensis) are fixed. The North African sparrow hybrids provide a further example of enhanced hybridization along with recent urbanization and anthropogenic land‐use changes in a mosaic landscape.Fil: Päckert, Martin. Leibniz Institution for Biodiversity and Earth System Research, Dresden; AlemaniaFil: Ait Belkacem, Abdelkrim. Université de Djelfa; ArgeliaFil: Wolfgramm, Hannes. Leibniz Institution for Biodiversity and Earth System Research, Dresden; AlemaniaFil: Gast, Oliver. Institute of Vertebrate Biology Brno y Masaryk University ; República ChecaFil: Canal Piña, David. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Giacalone, Gabriele. Cooperativa Silene; ItaliaFil: Lo Valvo, Mario. Universita Degli Studi Di Palermo.; ItaliaFil: Vamberger, Melita. Leibniz Institution for Biodiversity and Earth System Research, Dresden; AlemaniaFil: Wink, Michael. Ruprecht Karls Universitat Heidelberg.; AlemaniaFil: Martens, Jochen. Johannes Gutenberg Universitat Mainz; AlemaniaFil: Stuckas, Heiko. Leibniz Institution for Biodiversity and Earth System Research, Dresden; Alemani

    The anatomy, physiology, functional significance and evolution of specialized hearing organs of gerbilline rodents

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    Middle and inner ear anatomy correlates with neurophysiological responses to a wide range of sound frequencies for species of the Gerbillinae representing generalized, intermediate, and specialized anatomical conditions. Neurophysiological data were recorded from 81 specimens of 13 species representing six genera. Anatomical parameters involved in the process of hearing were correlated with the neurophysiological data to assess the effects of different degrees of anatomical specialization on hearing. The 13 species tested in this manner have graphic curves of auditory sensitivity of remarkably similar disposition over the frequencies tested and to those published for Kangaroo Rats. Ears with anatomical specializations show greater auditory sensitivity. The natural history of the Gerbillinae, particularly the kinds of predators, degree of predation, and habitat is reviewed and utilized to interpret the significance of the degree of auditory specialization in the forms studied and to evaluate the prevailing hypothesis that these specializations enhance the ability of these rodents to survive in open desert situations by detecting and evading predators. The middle ear anatomy of five additional genera and species was also studied. Thus, data on the entire spectrum of gerbilline middle ear morphology provide an evolutionary sequence. Certain anatomical parameters of the organ of Corti show a degree of specialization parallel to that of features of the middle ear. The morphological changes and possible functional roles of these features are considered. A very high correlation exists for degree of specialization and aridity of habitat, thus specialization increases with increasing aridity. This increased specialization may result from more effective predation in open xeric environments. Auditory acuity for a wide range of low frequency sounds augmented by auditory specialization is hence more advantageous here. There does not appear to be selection for hearing at particular frequencies in this range. The peaks of greatest auditory sensitivity appear to correspond to the resonant frequencies of the different components of the middle ear transformer and cavity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50256/1/1051380103_ftp.pd

    Franco-Japanese and other collaborative contributions to understanding chimpanzee culture at Bossou and the Nimba Mountains

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    The Japanese approach to science has permitted theoretical leaps in our understanding of culture in non-human animals and challenged human uniqueness, as it is not embedded in the Western traditional dualisms of human/animal and nature/culture. This paper highlights the value of an interdisciplinary approach and combining methodological approaches in exploring putative cultural variation among chimpanzees. I focus particularly on driver ants (Dorylus sp.) and oil palm (Elaeis guineensis) consumption among the Bossou and Nimba chimpanzees, in south-eastern Guinea at the border with Côte d’Ivoire and Liberia, and hand use across different tool use tasks commonly witnessed at Bossou, i.e. ant-dipping, nut-cracking, pestle-pounding, and algae-scooping. Observed variation in resource use was addressed across differing scales exploring both within- and between-community differences. Our findings have highlighted a tight interplay between ecology, social dynamics and culture, and between social and individual learning and maternal contribution to tool-use acquisition. Exploration of hand use by chimpanzees revealed no evidence for individual-level hand or community-level task specialisation. However, more complex types of tool use such as nut-cracking showed distinct lateralization, while the equivalent of a haptic manual action revealed a strong right hand bias. The data also suggest an overall population tendency for a right hand preference. As well as describing these sites’ key contributions to our understanding of chimpanzees and to challenging our perceptions of human uniqueness, this paper also highlights the critical condition and high levels of threats facing this emblematic chimpanzee population, and several questions that remain to be addressed. In the spirit of the Japanese approach to science, I recommend that an interdisciplinary and collaborative research approach can best help us to challenge perceptions of human uniqueness and to further our understanding of chimpanzee behavioural and social flexibility in the face of local social, ecological and anthropogenic changes and threats to their survival

    Note sur le comportement de Lucilia bufonivora Monniez

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    Heim de Balsac Henri. Note sur le comportement de Lucilia bufonivora Monniez. In: Bulletin de la Société entomologique de France, volume 38 (15),1933. pp. 236-239

    Les Soricidae dans le milieu d\ue9sertique saharien

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    Volume: 19Start Page: 181End Page: 18

    Myiase mortelle chez un Loir déterminée par Lucilia ampullacea Villen. Premières données sur la biologie de ce Diptère et considération sur le parasitisme chez les Lucilia

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    Heim de Balsac Henri. Myiase mortelle chez un Loir déterminée par Lucilia ampullacea Villen. Premières données sur la biologie de ce Diptère et considération sur le parasitisme chez les Lucilia. In: Bulletin de la Société entomologique de France, volume 42 (12),1937. pp. 179-182
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