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In tropical forests, anthropogenic activities are major drivers of the destruction and degradation of natural habitats, causing severe biodiversity loss. African colobine monkeys (Colobinae) are mainly folivore and strictly arboreal primates that require large forests to subsist, being among the most vulnerable of all nonhuman primates. The Western red colobus Piliocolobus badius and the King colobus Colobus polykomos inhabit highly fragmented West African forests, including the Cantanhez Forests National Park (CFNP) in Guinea-Bissau. Both species are also found in the largest and best-preserved West African forest?the Taï National Park (TNP) in Ivory Coast. Colobine monkeys are hunted for bushmeat in both protected areas, but these exhibit contrasting levels of forest fragmentation, thus offering an excellent opportunity to investigate the importance of well-preserved forests for the maintenance of evolutionary potential in these arboreal primates. We estimated genetic diversity, population structure, and demographic history by using microsatellite loci and mitochondrial DNA. We then compared the genetic patterns of the colobines from TNP with the ones previously obtained for CFNP and found contrasting genetic patterns. Contrary to the colobines from CFNP that showed very low genetic diversity and a strong population decline, the populations in TNP still maintain high levels of genetic diversity and we found no clear signal of population decrease in Western red colobus and a limited decrease in King colobus. These results suggest larger and historically more stable populations in TNP compared to CFNP. We cannot exclude the possibility that the demographic effects resulting from the recent increase of bushmeat hunting are not yet detectable in TNP using genetic data. Nevertheless, the fact that the TNP colobus populations are highly genetically diverse and maintain large effective population sizes suggests that well-preserved forests are crucial for the maintenance of populations, species, and probably for the evolutionary potential in colobines.

Determining the evolutionary basis of variation in reproductive skew (degree of sharing of reproduction among coexisting individuals) is an important task both because skew varies widely across social taxa and because testing models of skew evolution permits tests of kin selection theory. Using parentage analyses based on microsatellite markers, we measured skew among female eggs (n=32.3 eggs per colony, range=20-68) in 17 polygynous colonies from a UK field population of the ant Leptothorax acervorum. We used skew among eggs as our principal measure of skew because of the high degree of queen turnover in the study population. Queens within colonies did not make significantly unequal contributions to queen and worker adult or pupal offspring, indicating that skew among female eggs reflected skew among daughter queens. On average, both skew among female eggs (measured by the B index) and queen-queen relatedness proved to be low (means±SE=0.06±0.02 and 0.28±0.08, respectively). However, contrary to current skew models, there was no significant association of skew with either relatedness or worker number (used as a measure of productivity). In L. acervorum, predictions of the concession model of skew may hold between but not within populations because queens are unable to assess their relatedness to other queens within colonies. Additional phenomena that may help maintain low skew in the study population include indiscriminate infanticide in the form of egg cannibalism and split sex ratios that penalize reproductive monopoly by single queens within polygynous colonies

In the last decades, several endangered breeds of livestock species have been re-established effectively. However, the successful revival of the Dutch and Danish Landrace goats involved crossing with exotic breeds and the ancestry of the current populations is therefore not clear. We have generated genotypes for 27 FAO-recommended microsatellites of these landraces and three phenotypically similar Nordic-type landraces and compared these breeds with central European, Mediterranean and south-west Asian goats. We found decreasing levels of genetic diversity with increasing distance from the south-west Asian domestication site with a south-east-to-north-west cline that is clearly steeper than the Mediterranean east-to-west cline. In terms of genetic diversity, the Dutch Landrace comes next to the isolated Icelandic breed, which has an extremely low diversity. The Norwegian coastal goat and the Finnish and Icelandic landraces are clearly related. It appears that by a combination of mixed origin and a population bottleneck, the Dutch and Danish Land-races are separated from the other breeds. However, the current Dutch and Danish populations with the multicoloured and long-horned appearance effectively substitute for the original breed, illustrating that for conservation of cultural heritage, the phenotype of a breed is more relevant than pure ancestry and the genetic diversity of the original breed. More in general, we propose that for conservation, the retention of genetic diversity of an original breed and of the visual phenotype by which the breed is recognized and defined needs to be considered separately., Stichting Zeldzame Huisdierassen

Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits.

Background\ud During the past decades, neutral DNA markers have been extensively employed to study demography, population genetics and structure in livestock, but less interest has been devoted to the evaluation of livestock adaptive potential through the identification of genomic regions likely to be under natural selection.\ud \ud Methodology/Principal findings\ud Landscape genomics can greatly benefit the entire livestock system through the identification of genotypes better adapted to specific or extreme environmental conditions. Therefore we analyzed 101 AFLP markers in 43 European and Western Asian goat breeds both with Matsam software, based on a correlative approach (SAM), and with Mcheza and Bayescan, two FST based software able to detect markers carrying signatures of natural selection.\ud \ud Matsam identified four loci possibly under natural selection – also confirmed by FST-outlier methods – and significantly associated with environmental variables such as diurnal temperature range, frequency of precipitation, relative humidity and solar radiation.\ud \ud Conclusions/Significance\ud These results show that landscape genomics can provide useful information on the environmental factors affecting the adaptive potential of livestock living in specific climatic conditions. Besides adding conservation value to livestock genetic resources, this knowledge may lead to the development of novel molecular tools useful to preserve the adaptive potential of local breeds during genetic improvement programs, and to increase the adaptability of industrial breeds to changing environments.

Chantier qualité GA Liste des auteurs de l'European Cattle Genetic Consortium, classés par pays : Austria: R. Baumung, S. Manatrinon, BOKU University, Vienna; Belgium: G. Mommens, University of Ghent, Merelbeke; Denmark: L.-E. Holm, Aarhus University, Tjele; K.B. Withen, B.V. Pedersen, P. Gravlund, University of Copenhagen, Copenhagen; Estonia: H. Viinalass, Estonian University of Life Sciences, Tartu; Finland: J. Kantanen, I. Tapio, M.H. Li, MTT, Jokioinen; France: K. Moazami-Goudarzi, M. Gautier, Denis Laloë, INRA, Jouy-en-Josas; A. Oulmouden, H. Levéziel, INRA, Limoges; P. Taberlet, Université Joseph Fourier et CNRS, Grenoble; Germany: B. Harlizius, School of Veterinary Medicine, Hannover; H. Simianer, H. Täubert, Georg-August-Universität, Göttingen; G. Erhardt, O. Jann, C. Weimann, E.-M. Prinzenberg, Justus-Liebig Universität, Giessen; I. Medugorac, A. Medugorac, M. Förster, Ludwig-Maximilians Universität, Munich; H.M. Mix, Naturschutz International, Grünheide; C. Looft, E. Kalm, Christian-Albrechts-Universität, Kiel; Ireland: D.G. Bradley, C.J. Edwards, D.E. MacHugh, A.R. Freeman, Trinity College, Dublin; Italy: P. Ajmone Marsan, R. Negrini, Università Cattolica del S. Cuore, Piacenza; M. Longeri, G. Ceriotti, M. Zanotti, Università degli Studi di Milano; D. Marletta, A. Criscione, Universita degli Studi di Catania, Catania; A. Valentini, C. Marchitelli, L. Pariset, M.C. Savarese, Università della Tuscia, Viterbo; F. Pilla, Università del Molise, Campobasso; Latvia: Z. Grislis, Latvia University of Agriculture, Jelgava; Lithuania: I. Miceikienė, Lithuanian Veterinary Academy, Kaunas; Netherlands: I.J. Nijman, Utrecht University; W. van Haeringen, L. van de Goor, Van Haeringen Laboratory, Wageningen; Norway: I. Olsaker, Norwegian School of Veterinary Science, Oslo; Portugal: C. Ginja, L.T.Gama, Instituto Nacional de Recursos Biológicos—INIA, Lisbon University, Lisboa; L.T. Gama, Instituto Nacional de Recursos Biológicos-INIA, I.P., Vale de Santarem; J.C. Mateus, Universidade de Trás-os-Montes e Alto Douro, Vila Real; A. Beja-Pereira, N. Ferrand, Oporto University; Russia: Z. Ivanova, R. Popov, I. Ammosov, Yakutian Research Institute of Agricultural Sciences, Yakutsk, Sakha; T. Kiselyova, All-Russian Research Institute for Farm Animals and Breeding, St. Petersburgh-Pushkin; N. Marzanov, All-Russian Research Institute of Animal Husbandry, Dubrovitsy; Serbia: S. Stojanovic, Ministry of Agriculture and Water Management, Belgrade; Slovenia: M. Simčič, P. Dovč, D.Kompan, University of Ljubljana, Domzale; Spain: S. Dunner, Universidad Complutense de Madrid; C. Rodellar, I. Martín-Burriel, Veterinary Faculty, Zaragoza; A. Sánchez, J. Piedrafita, Universitat Autònoma de Barcelona; P.J. Azor, J.V. Delgado, A. Martínez-Martínez, A. Molina, E. Rodero, University of Córdoba; Switzerland: G. Dolf, University of Berne; UK: J.L. Williams, P. Wiener, Roslin Institute; M.W. Bruford, T.C. Bray, Cardiff University, Cardiff; L. Alderson, Countrywide Livestock Ltd, Shrewsbury; USA: M.C.T. Penedo. University of California, Davis, CA; International audience; Classification of cattle breeds contributes to our understanding of the history of cattle and is essential for an effective conservation of genetic diversity. Here we review the various classifications over the last two centuries and compare the most recent classifications with genetic data. The classifications devised during the 19th to the late 20th century were in line with the Linnaean taxonomy and emphasized cranial or horn morphology. Subsequent classifications were based on coat color, geographic origin or molecular markers. Several theories were developed that linked breed characteristics either to a supposed ancestral aurochs subspecies or to a presumed ethnic origin. Most of the older classifications have now been discarded, but have introduced several Latin terms that are still in use. The most consistent classification was proposed in 1995 by Felius and emphasizes the geographic origin of breeds. This is largely in agreement with the breed clusters indicated by a biochemical and molecular genetic analysis, which reflect either groups of breeds with a common geographic origin or single breeds that have expanded by export and/or crossbreeding. We propose that this information is also relevant for managing the genetic diversity of cattle.