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4. Antarctic Fur Seal (Arctocephalus gazella, Peters 1875).

Author

Heckel, G., Schramm, Y., Forcada, J., Heckel, G., Schramm, Y., and Forcada, J.

Abstract

The Antarctic fur seal lives south of the Antarctic Polar Front and has never been reported breeding in Latin America. Individuals encountered occasionally, from Peru, norther Chile, and the Juan Fernandez Archipelago to South Brazil, are likely to be vagrants from the populations of the sub-Antarctic archipelago of South Georgia and the South Shetland Islands, Antarctic Peninsula. The species is one of the smaller otariids, has a short lactation of less than 4 months, is highly sexually dimorphic, and has a high polygyny. This determines its reproductive behavior and different foraging strategies, distribution, and diet between sexes. Breeding females alternate 2- to 11-day foraging trips at sea with 1- to 3-day nursing periods on land during lactation, which constraints their foraging range and breeding success. Bulls start holding breeding territories at ages 8-9, but most will be unsuccessful, especially in densely populated areas. In the Southwest Atlantic, Antarctic fur seals are important secondary consumers and highly dependent on Antarctic krill, which is a very abundant but variable resource. Most of the world population occurs at South Georgia, where some colonies are declining because of climate effects on the food supply. Currently of least concern, its conservation status requires re-assessment with up-to-date populations evaluations.

Published
2021

5. Geographical Distribution and Genetic Diversity of Bank Vole Hepaciviruses in Europe

Author

Schneider, J, Hoffmann, B, Fevola, C, Schmidt, ML, Imholt, C, Fischer, S, Ecke, F, Hoernfeldt, B, Magnusson, M, Olsson, GE, Rizzoli, A, Tagliapietra, V, Chiari, M, Reusken, C, Buzan, E, Kazimirova, M, Stanko, M, White, TA, Reil, D, Obiegala, A, Meredith, A, Drexler, JF, Essbauer, S, Henttonen, H, Jacob, J, Hauffe, HC, Beer, M, Heckel, G, Ulrich, RG, Schneider, J, Hoffmann, B, Fevola, C, Schmidt, ML, Imholt, C, Fischer, S, Ecke, F, Hoernfeldt, B, Magnusson, M, Olsson, GE, Rizzoli, A, Tagliapietra, V, Chiari, M, Reusken, C, Buzan, E, Kazimirova, M, Stanko, M, White, TA, Reil, D, Obiegala, A, Meredith, A, Drexler, JF, Essbauer, S, Henttonen, H, Jacob, J, Hauffe, HC, Beer, M, Heckel, G, and Ulrich, RG

Abstract

The development of new diagnostic methods resulted in the discovery of novel hepaciviruses in wild populations of the bank vole (Myodes glareolus, syn. Clethrionomys glareolus). The naturally infected voles demonstrate signs of hepatitis similar to those induced by hepatitis C virus (HCV) in humans. The aim of the present research was to investigate the geographical distribution of bank vole-associated hepaciviruses (BvHVs) and their genetic diversity in Europe. Real-time reverse transcription polymerase chain reaction (RT-qPCR) screening revealed BvHV RNA in 442 out of 1838 (24.0%) bank voles from nine European countries and in one of seven northern red-backed voles (Myodes rutilus, syn. Clethrionomys rutilus). BvHV RNA was not found in any other small mammal species (n = 23) tested here. Phylogenetic and isolation-by-distance analyses confirmed the occurrence of both BvHV species (Hepacivirus F and Hepacivirus J) and their sympatric occurrence at several trapping sites in two countries. The broad geographical distribution of BvHVs across Europe was associated with their presence in bank voles of different evolutionary lineages. The extensive geographical distribution and high levels of genetic diversity of BvHVs, as well as the high population fluctuations of bank voles and occasional commensalism in some parts of Europe warrant future studies on the zoonotic potential of BvHVs.

Published
2021

6. Nagetiere und Nagetierassoziierte Krankheitserreger: Das Netzwerk „Nagetier-übertragene Pathogene“ stellt sich vor

Author

Ulrich, Rainer G., Heckel, G., Pelz, H.-J., Wieler, L. H., Nordhoff, M., Dobler, G., Freise, J., Matuschka, F.-R., Jacob, J., Schmidt-Chanasit, J., Gerstengarbe, F. W., Jäkel, T., Süss, J., Ehlers, B., Nitsche, A., Kallies, R., Johne, R., Günther, S., Henning, K., Grunow, R., Wenk, M., Maul, L. C., Hunfeld, K.-P., Wölfel, R., Schares, G., Scholz, H. C., Brockmann, S. O., Pfeffer, M., and Essbauer, S. S.

Published
2009
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7. Network “Rodent-borne pathogens” in Germany: longitudinal studies on the geographical distribution and prevalence of hantavirus infections

Author

Ulrich, R. G., Schmidt-Chanasit, J., Schlegel, M., Jacob, J., Pelz, H.-J., Mertens, M., Wenk, M., Büchner, T., Masur, D., Sevke, K., Groschup, M. H., Gerstengarbe, F.-W., Pfeffer, M., Oehme, R., Wegener, W., Bemmann, M., Ohlmeyer, L., Wolf, R., Zoller, H., Koch, J., Brockmann, S., Heckel, G., and Essbauer, S. S.

Published
2008
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8. Comparative swimming effort of migrating gray whales (Eschrichtius robustus) and calf cost of transport along Costa Azul, Baja California, Mexico

Author

de la Gala-Hernandez, S. Rodriguez, Heckel, G., and Sumich, J.L.

Subjects
Animal swimming -- Physiological aspects -- Behavior, Gray whale -- Physiological aspects -- Behavior, Animal migration -- Physiological aspects -- Behavior, Zoology and wildlife conservation, Physiological aspects, Behavior
Abstract

Abstract: Swimming velocities and breathing rates were measured for migrating gray whales (Eschrichtius robustus (Lilljeborg, 1861)) at Costa Azul, Baja California, to compare swimming effort of southbound whales, northbound whales [...]

Published
2008

14. Hantavirus- coinfections in small mammals from central Germany.

Author

Jeske, K., Jacob, J., Drewes, S., Pfeffer, M., Heckel, G., Ulrich, R. G., and Imholt, C.

Abstract

European orthohantaviruses (Puumala orthohantavirus (PUUV); Dobrava-Belgrade orthohantavirus (DOBV), genotype Kurkino; Tula orthohantavirus (TULV)), and Leptospira spp. are small mammal-associated zoonotic pathogens that cause diseases with potentially similar symptoms in humans. We investigated the frequency of Leptospira spp. and hantavirus single and double infections in small mammals from 22 sites in Thuringia, central Germany, during 2017. TULV infections were detected at 18 of 22 sites (mean prevalence 13.8%, 93/674). PUUV infections were detected at four of 22 sites (mean prevalence 1.5%, 7/471), and respective PUUV sequences formed a novel phylogenetic clade, but DOBV infections were not detected at all. Leptospira infections were detected at 21 of 22 sites with the highest overall prevalence in field voles (Microtus agrestis) with 54.5% (6/11) and common voles (Microtus arvalis) with 30.3% (205/676). Leptospira-hantavirus coinfections were found in 6.6% (44/671) of common voles but only in two of 395 bank voles. TULV and Leptospira coinfection probability in common voles was driven by individual (age) and population-level factors. Coinfections seemed to be particularly associated with sites where Leptospira spp. prevalence exceeded 35%. Future investigations should evaluate public health consequences of this strong spatial clustering of coinfections. [ABSTRACT FROM AUTHOR]

Published
2021
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17. The SIB Swiss Institute of Bioinformatics' resources: focus on curated databases

Author

Bultet, LA, Aguilar-Rodriguez, J, Ahrens, CH, Ahrne, EL, Ai, N, Aimo, L, Akalin, A, Aleksiev, T, Alocci, D, Altenhoff, A, Alves, I, Ambrosini, G, Pedone, PA, Angelina, P, Anisimova, M, Appel, R, Argoud-Puy, G, Arnold, K, Arpat, B, Artimo, P, Ascencao, K, Auchincloss, A, Axelsen, K, Gerritsen, VB, Bairoch, A, Barisal, P, Baratin, D, Barbato, A, Barbie, V, Barras, D, Barreiro, M, Barret, S, Bastian, F, Batista Neto, TM, Baudis, M, Beaudoing, E, Beckmann, JS, Bekkar, AK, Cammoun, LBH, Benmohammed, S, Bernard, M, Bertelli, C, Bertoni, M, Bienert, S, Bignucolo, O, Bilbao, A, Bilican, A, Blank, D, Blatter, M-C, Blum, L, Bocquet, J, Boeckmann, B, Bolleman, JT, Bordoli, L, Bosshard, L, Boucher, G, Bougueleret, L, Boutet, E, Bovigny, C, Bratulic, S, Breuza, L, Bridge, AJ, Britan, A, Brito, F, Frazao, JB, Bruggmann, R, Bucher, P, Burdet, F, Burger, L, Cabello, EM, Gomez, RMC, Calderon, S, Cannarozzi, G, Carl, S, Casas, CC, Catherinet, S, Perier, RC, Charpilloz, C, Chaskar, PD, Chen, W, Pepe, AC, Chopard, B, Chu, HY, Civic, N, Claassen, M, Clottu, S, Colombo, M, Cosandier, I, Coudert, E, Crespo, I, Creus, M, Cuche, B, Cuendet, MA, Cusin, I, Daga, N, Daina, A, Dauvillier, J, David, F, Davydov, I, Ferreira, MDSRM, de Beer, T, de Castro, E, de Santana, C, Delafontaine, J, Delorenzi, M, Delucinge-Vivier, C, Demirel, O, Derham, R, Dermitzakis, EM, Dib, L, Diene, S, Dilek, N, Dilmi, J, Domagalski, MJ, Dorier, J, Dornevil, D, Dousse, A, Dreos, R, Duchen, P, Roggli, PD, Duperret, ID, Durinx, C, Duvaud, S, Engler, R, Frkek, S, Lopez, PE, Fstreicher, A, Excoffier, L, Fabbretti, R, Falcone, J-L, Falquet, L, Famiglietti, ML, Ferreira, A-M, Feuermann, M, Filliettaz, M, Hegel, V, Foucal, A, Franceschini, A, Fucile, G, Gaidatzis, D, Garcia, V, Gasteiger, E, Gateau, A, Gatti, L, Gaudet, P, Gaudinat, A, Gehant, S, Gfeller, D, Gharib, WH, Ghraichy, M, Gidoin, C, Gil, M, Gleizes, A, Gobeill, J, Gonnet, G, Gos, A, Gotz, L, Gouy, A, Grbic, D, Groux, R, Gruaz-Gumowski, N, Grun, D, Gschwind, A, Guex, N, Gupta, S, Getaz, M, Haake, D, Haas, J, Hatzimanikatis, V, Heckel, G, Gardiol, DFH, Hinard, V, Hinz, U, Homicsko, K, Horlacher, O, Hosseini, S-R, Hotz, H-R, Hulo, C, Hundsrucker, C, Ibberson, M, Ilmjarv, S, Ioannidis, V, Ioannidis, P, Iseli, C, Ivanek, R, Iwaszkiewicz, J, Jacquet, P, Jacquot, M, Jagannathan, V, Jan, M, Jensen, J, Johansson, MU, Johner, N, Jungo, F, Junier, T, Kahraman, A, Katsantoni, M, Keller, G, Kerhornou, A, Khalid, F, Klingbiel, D, Kimljenovic, A, Kriventseva, E, Kryuchkova, N, Kumar, S, Kutalik, Z, Kuznetsov, D, Kuzyakiv, R, Lane, L, Lara, V, Ledesma, L, Leleu, M, Lemercier, P, Lew, D, Lieberherr, D, Liechti, R, Lisacek, F, Fischer, H, Litsios, G, Liu, J, Lombardot, T, Mace, A, Maffioletti, S, Mahi, M-A, Maiolo, M, Majjigapu, SR, Malmstrom, L, Mangold, V, Marek, D, Mariethoz, J, Marin, R, Martin, O, Martin, X, Martin-Campos, T, Mary, C, Masclaux, F, Masson, P, Meier, C, Messina, A, Lenoir, MM, Meyer, X, Michel, P-A, Michielin, O, Milanese, A, Missiaglia, E, Perez, JM, Caria, VM, Moret, P, Moretti, S, Morgat, A, Mottaz, A, Mottin, L, Mouscaz, Y, Mueller, M, Murri, R, Mylonas, R, Neuenschwander, S, Nikitin, F, Niknejad, A, Nouspikel, N, Nso, LN, Okoniewski, M, Omasits, U, Paccaud, B, Pachkov, M, Paesano, SG, Pagni, M, Palagi, PM, Pasche, E, Payne, JL, Pedruzzi, I, Peischl, S, Peitsch, M, Perlini, S, Pilbout, S, Podvinec, M, Pohlmann, R, Polizzi, D, Potter, D, Poux, S, Pozzato, M, Pradervand, S, Praz, V, Pruess, M, Pujadas, E, Racle, J, Raschi, M, Ratib, O, Rausell, A, de Laval, VR, Redaschi, N, Rempfer, C, Ren, G, Vandati, RAR, Rib, L, Grognuz, OR, Altimiras, ER, Rivoire, C, Robin, T, Robinson-Rechavi, M, Rodrigues, J, Roechert, B, Roelli, P, Romano, V, Rossier, G, Roth, A, Rougemont, J, Roux, J, Royo, H, Ruch, P, Ruinelli, M, Rustom, M, Sates, A, Roehrig, UF, Rueeger, S, Salamin, N, Sankar, M, Sarkar, N, Saxenhofer, M, Schaeffer, M, Schaerli, Y, Schaper, E, Schmid, A, Schmid, E, Schmid, C, Schmid, M, Schmidt, S, Schmocker, D, Schneider, M, Schuepbach, T, Schwede, T, Schuetz, F, Sengstag, T, Serrano, M, Sethi, A, Shahmirzadi, O, Sigrist, C, Silvestro, D, Simao Neto, FA, Simillion, C, Simonovic, M, Skunca, N, Sluzek, K, Soneson, C, Sprouffske, K, Stadler, M, Staehli, S, Stevenson, B, Stockinger, H, Straszewski, J, Stricker, T, Studer, G, Stutz, A, Suffiotti, M, Sundaram, S, Szklarczyk, D, Szovenyi, P, Tegenfeldt, F, Teixeira, D, Tellenbach, S, Smith, AAT, Tognolli, M, Topolsky, I, Thuong, VDT, Tsantoulis, P, Tzika, AC, Agote, AU, van Nimwegen, E, von Mering, C, Varadarajan, A, Veranneman, M, Verbregue, L, Veuthey, A-L, Vishnyakova, D, Vyas, R, Wagner, A, Walther, D, Wan, HW, Wang, M, Waterhouse, R, Waterhouse, A, Wicki, A, Wigger, L, Wirapati, P, Witschi, U, Wyder, S, Wyler, K, Wuethrich, D, Xenarios, I, Yamada, K, Yan, Z, Yasrebi, H, Zahn, M, Zangger, N, Zdobnov, E, Zerzion, D, Zoete, V, Zoller, S, Bultet, LA, Aguilar-Rodriguez, J, Ahrens, CH, Ahrne, EL, Ai, N, Aimo, L, Akalin, A, Aleksiev, T, Alocci, D, Altenhoff, A, Alves, I, Ambrosini, G, Pedone, PA, Angelina, P, Anisimova, M, Appel, R, Argoud-Puy, G, Arnold, K, Arpat, B, Artimo, P, Ascencao, K, Auchincloss, A, Axelsen, K, Gerritsen, VB, Bairoch, A, Barisal, P, Baratin, D, Barbato, A, Barbie, V, Barras, D, Barreiro, M, Barret, S, Bastian, F, Batista Neto, TM, Baudis, M, Beaudoing, E, Beckmann, JS, Bekkar, AK, Cammoun, LBH, Benmohammed, S, Bernard, M, Bertelli, C, Bertoni, M, Bienert, S, Bignucolo, O, Bilbao, A, Bilican, A, Blank, D, Blatter, M-C, Blum, L, Bocquet, J, Boeckmann, B, Bolleman, JT, Bordoli, L, Bosshard, L, Boucher, G, Bougueleret, L, Boutet, E, Bovigny, C, Bratulic, S, Breuza, L, Bridge, AJ, Britan, A, Brito, F, Frazao, JB, Bruggmann, R, Bucher, P, Burdet, F, Burger, L, Cabello, EM, Gomez, RMC, Calderon, S, Cannarozzi, G, Carl, S, Casas, CC, Catherinet, S, Perier, RC, Charpilloz, C, Chaskar, PD, Chen, W, Pepe, AC, Chopard, B, Chu, HY, Civic, N, Claassen, M, Clottu, S, Colombo, M, Cosandier, I, Coudert, E, Crespo, I, Creus, M, Cuche, B, Cuendet, MA, Cusin, I, Daga, N, Daina, A, Dauvillier, J, David, F, Davydov, I, Ferreira, MDSRM, de Beer, T, de Castro, E, de Santana, C, Delafontaine, J, Delorenzi, M, Delucinge-Vivier, C, Demirel, O, Derham, R, Dermitzakis, EM, Dib, L, Diene, S, Dilek, N, Dilmi, J, Domagalski, MJ, Dorier, J, Dornevil, D, Dousse, A, Dreos, R, Duchen, P, Roggli, PD, Duperret, ID, Durinx, C, Duvaud, S, Engler, R, Frkek, S, Lopez, PE, Fstreicher, A, Excoffier, L, Fabbretti, R, Falcone, J-L, Falquet, L, Famiglietti, ML, Ferreira, A-M, Feuermann, M, Filliettaz, M, Hegel, V, Foucal, A, Franceschini, A, Fucile, G, Gaidatzis, D, Garcia, V, Gasteiger, E, Gateau, A, Gatti, L, Gaudet, P, Gaudinat, A, Gehant, S, Gfeller, D, Gharib, WH, Ghraichy, M, Gidoin, C, Gil, M, Gleizes, A, Gobeill, J, Gonnet, G, Gos, A, Gotz, L, Gouy, A, Grbic, D, Groux, R, Gruaz-Gumowski, N, Grun, D, Gschwind, A, Guex, N, Gupta, S, Getaz, M, Haake, D, Haas, J, Hatzimanikatis, V, Heckel, G, Gardiol, DFH, Hinard, V, Hinz, U, Homicsko, K, Horlacher, O, Hosseini, S-R, Hotz, H-R, Hulo, C, Hundsrucker, C, Ibberson, M, Ilmjarv, S, Ioannidis, V, Ioannidis, P, Iseli, C, Ivanek, R, Iwaszkiewicz, J, Jacquet, P, Jacquot, M, Jagannathan, V, Jan, M, Jensen, J, Johansson, MU, Johner, N, Jungo, F, Junier, T, Kahraman, A, Katsantoni, M, Keller, G, Kerhornou, A, Khalid, F, Klingbiel, D, Kimljenovic, A, Kriventseva, E, Kryuchkova, N, Kumar, S, Kutalik, Z, Kuznetsov, D, Kuzyakiv, R, Lane, L, Lara, V, Ledesma, L, Leleu, M, Lemercier, P, Lew, D, Lieberherr, D, Liechti, R, Lisacek, F, Fischer, H, Litsios, G, Liu, J, Lombardot, T, Mace, A, Maffioletti, S, Mahi, M-A, Maiolo, M, Majjigapu, SR, Malmstrom, L, Mangold, V, Marek, D, Mariethoz, J, Marin, R, Martin, O, Martin, X, Martin-Campos, T, Mary, C, Masclaux, F, Masson, P, Meier, C, Messina, A, Lenoir, MM, Meyer, X, Michel, P-A, Michielin, O, Milanese, A, Missiaglia, E, Perez, JM, Caria, VM, Moret, P, Moretti, S, Morgat, A, Mottaz, A, Mottin, L, Mouscaz, Y, Mueller, M, Murri, R, Mylonas, R, Neuenschwander, S, Nikitin, F, Niknejad, A, Nouspikel, N, Nso, LN, Okoniewski, M, Omasits, U, Paccaud, B, Pachkov, M, Paesano, SG, Pagni, M, Palagi, PM, Pasche, E, Payne, JL, Pedruzzi, I, Peischl, S, Peitsch, M, Perlini, S, Pilbout, S, Podvinec, M, Pohlmann, R, Polizzi, D, Potter, D, Poux, S, Pozzato, M, Pradervand, S, Praz, V, Pruess, M, Pujadas, E, Racle, J, Raschi, M, Ratib, O, Rausell, A, de Laval, VR, Redaschi, N, Rempfer, C, Ren, G, Vandati, RAR, Rib, L, Grognuz, OR, Altimiras, ER, Rivoire, C, Robin, T, Robinson-Rechavi, M, Rodrigues, J, Roechert, B, Roelli, P, Romano, V, Rossier, G, Roth, A, Rougemont, J, Roux, J, Royo, H, Ruch, P, Ruinelli, M, Rustom, M, Sates, A, Roehrig, UF, Rueeger, S, Salamin, N, Sankar, M, Sarkar, N, Saxenhofer, M, Schaeffer, M, Schaerli, Y, Schaper, E, Schmid, A, Schmid, E, Schmid, C, Schmid, M, Schmidt, S, Schmocker, D, Schneider, M, Schuepbach, T, Schwede, T, Schuetz, F, Sengstag, T, Serrano, M, Sethi, A, Shahmirzadi, O, Sigrist, C, Silvestro, D, Simao Neto, FA, Simillion, C, Simonovic, M, Skunca, N, Sluzek, K, Soneson, C, Sprouffske, K, Stadler, M, Staehli, S, Stevenson, B, Stockinger, H, Straszewski, J, Stricker, T, Studer, G, Stutz, A, Suffiotti, M, Sundaram, S, Szklarczyk, D, Szovenyi, P, Tegenfeldt, F, Teixeira, D, Tellenbach, S, Smith, AAT, Tognolli, M, Topolsky, I, Thuong, VDT, Tsantoulis, P, Tzika, AC, Agote, AU, van Nimwegen, E, von Mering, C, Varadarajan, A, Veranneman, M, Verbregue, L, Veuthey, A-L, Vishnyakova, D, Vyas, R, Wagner, A, Walther, D, Wan, HW, Wang, M, Waterhouse, R, Waterhouse, A, Wicki, A, Wigger, L, Wirapati, P, Witschi, U, Wyder, S, Wyler, K, Wuethrich, D, Xenarios, I, Yamada, K, Yan, Z, Yasrebi, H, Zahn, M, Zangger, N, Zdobnov, E, Zerzion, D, Zoete, V, and Zoller, S

Abstract

The SIB Swiss Institute of Bioinformatics (www.isb-sib.ch) provides world-class bioinformatics databases, software tools, services and training to the international life science community in academia and industry. These solutions allow life scientists to turn the exponentially growing amount of data into knowledge. Here, we provide an overview of SIB's resources and competence areas, with a strong focus on curated databases and SIB's most popular and widely used resources. In particular, SIB's Bioinformatics resource portal ExPASy features over 150 resources, including UniProtKB/Swiss-Prot, ENZYME, PROSITE, neXtProt, STRING, UniCarbKB, SugarBindDB, SwissRegulon, EPD, arrayMap, Bgee, SWISS-MODEL Repository, OMA, OrthoDB and other databases, which are briefly described in this article.

Published
2016

19. Life-stage specific environments in a cichlid fish: Implications for inducible maternal effects

Author

Kotrschal, A., Heckel, G., Bonfils, D., Taborsky, B., Kotrschal, A., Heckel, G., Bonfils, D., and Taborsky, B.

Abstract

Through environmentally induced maternal effects females may fine-tune their offspring's phenotype to the conditions offspring will encounter after birth. If juvenile and adult ecologies differ, the conditions that mothers experienced as juveniles may better predict their offspring's environment than the adult females' ambient conditions. Maternal effects induced by the environment experienced by females during their early ontogeny should evolve when three ecological conditions are met: (i) Adult ecology does not predict the postnatal environmental conditions of offspring; (ii) Environmental conditions for juveniles are correlated across successive generations; and (iii) Juveniles occasionally settle in conditions that differ from the juvenile habitat of their mothers. By combining size-structured population counts, ecological surveys and a genetic analysis of population structure we provide evidence that all three conditions hold for Simochromis pleurospilus, a cichlid fish in which mothers adjust offspring quality to their own juvenile ecology. Adults of many species cannot predict offspring's environment from ambient cues. Hence we predict that life-stage specific maternal effects are common in animals. Therefore, it is important to incorporate parental ontogeny in the study of parental effects when juveniles and adults inhabit different environments.

Published
2012

20. Asymmetric and differential gene introgression at a contact zone between two highly divergent lineages of field voles (Microtus agrestis)

Author

Beysard, M, Perrin, N, Jaarola, Maarit, Heckel, G, Vogel, P, Beysard, M, Perrin, N, Jaarola, Maarit, Heckel, G, and Vogel, P

Abstract

Secondary contact zones have the potential to shed light on the mode and rate at which reproductive isolation accumulates during allopatric speciation. We investigated the population genetics of a contact zone between two highly divergent lineages of field voles (Microtus agrestis) in the Swiss Jura mountains. To shed light on the processes underlying introgression, we used maternally, paternally, and bi-parentally inherited markers. Though the two lineages maintained a strong genetic structure, we found some hybrids and evidence of gene flow. The extent of introgression varied with the mode of inheritance, being highest for mtDNA and absent for the Y chromosome. In addition, introgression was asymmetric, occurring only from the Northern to the Southern lineage. Both patterns seem parsimoniously explained by neutral processes linked to differences in effective sizes and sex-biased dispersal rates. The lineage with lower effective population size was also the more introgressed, and the mode-of-inheritance effect correlated with the male-biased dispersal rate of microtine rodents. We cannot exclude, however, that Haldanes effect contributed to the latter, as we found a marginally significant deficit in males (the heterogametic sex) among hybrids. We propose a possible demographic scenario to account for the patterns documented, and empirical extensions to further investigate this contact zone., Funding Agencies|Basler Stiftung fur Biologische Forschung||Agassiz Fondation||University of Lausanne||Swiss National Science foundation|31003A-12737731003A-108100

Published
2012
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22. Genetic structure and colonization processes in European populations of the common vole, Microtus arvalis

Author

Heckel, G, Burri, Reto, Fink, S, Desmet, J F, Excoffier, L, Heckel, G, Burri, Reto, Fink, S, Desmet, J F, and Excoffier, L

Abstract

The level of genetic differentiation within and between evolutionary lineages of the common vole (Microtusarvalis) in Europe was examined by analyzing mitochondrial sequences from the control region (mtDNA) and 12nuclear microsatellite loci (nucDNA) for 338 voles from 18 populations. The distribution of evolutionary lineagesand the affinity of populations to lineages were determined with additional sequence data from the mitochondrialcytochrome b gene. Our analyses demonstrated very high levels of differentiation between populations (overall FST:mtDNA 70%; nucDNA 17%). The affinity of populations to evolutionary lineages was strongly reflected in mtDNAbut not in nucDNA variation. Patterns of genetic structure for both markers visualized in synthetic genetic mapssuggest a postglacial range expansion of the species into the Alps, as well as a potentially more ancient colonizationfrom the northeast to the southwest of Europe. This expansion is supported by estimates for the divergence timesbetween evolutionary lineages and within the western European lineage, which predate the last glacial maximum(LGM). Furthermore, all measures of genetic diversity within populations increased significantly with longitude andshowed a trend toward increase with latitude. We conclude that the detected patterns are difficult to explain only byrange expansions from separate LGM refugia close to the Mediterranean. This suggests that someM. arvalis populationspersisted during the LGM in suitable habitat further north and that the gradients in genetic diversity may representtraces of a more ancient colonization of Europe by the species.

Published
2005

33. Seasonal variability of copepods and cladocerans in Bahía de los Ángeles (Gulf of California) and importance of Acartia clausi as food for whale sharks.

Author

Lavaniegos, B. E., Heckel, G., and Ladrón de Guevara P, P.

Subjects
*MARINE zooplankton, *PLANKTON populations, *SEASONS, *MARINE animals, *WHALE shark, *ANIMAL feeding behavior
Abstract

Bahía de los Ángeles is located on the Baja Californian coast of the Gulf of California, adjacent to Ballenas Channel. The bay receives a dynamic tidal influence from the channel but is protected by numerous islands. It is a highly productive bay that harbors a high diversity of species, some of them protected such as the whale shark (Rhincodon typus). This study describes the seasonal variability of major zooplankton taxa and copepod and cladoceran species between May 2003 and October 2004. Copepods were dominant during winter and spring (83-99% of the zooplankton abundance), experiencing a dramatic decrease in autumn 2003 (37-66%) and summer 2004 (25-45%). Cladocerans were the second most abundant group, represented by Pseudevadne tergestina and Penilia avirostris. The former species occurred year-round with low abundance in winter, whereas the latter occurred only in summer and autumn. Other holozooplankton taxa contributed with less than 15% of the abundance in most of the samples, while merozooplankton contributed less than 8%, though in October of 2003 and 2004 there was a remarkable abundance of echinoderms and other larvae contrasting with their shortage in other seasons. In winter 2004, temperate-subtropical copepod species dominated, such as Calanus pacificus and Acartia tonsa. The high abundance of copepods during spring obeyed to Acartia clausi (median = 28,034 ind m-3); however, the maximal zooplankton abundance (40,468 ind m-3, 99.5% copepods) came from a sample collected south of Punta Arena, where two whale sharks were observed foraging. The shift in species composition during summer coincides with the predominance of easterly winds described in the literature inducing a reversed circulation and a probable transport of tropical species into the bay during summer and autumn (Centropages furcatus, Subeucalanus subcrassus, Acrocalanus longicornis, Temora discaudata, and Corycaeus amazonicus). [ABSTRACT FROM AUTHOR]

Published
2012
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34. Novel hepatitis E virus genotype in Norway rats, Germany.

Author

Johne R, Heckel G, Plenge-Bonig A, Kindler E, Maresch C, Reetz J, Schielke A, Ulrich RG, Johne, Reimar, Heckel, Gerald, Plenge-Bönig, Anita, Kindler, Eveline, Maresch, Christina, Reetz, Jochen, Schielke, Anika, and Ulrich, Rainer G

Abstract

Human hepatitis E virus infections may be caused by zoonotic transmission of virus genotypes 3 and 4. To determine whether rodents are a reservoir, we analyzed the complete nucleotide sequence of a hepatitis E-like virus from 2 Norway rats in Germany. The sequence suggests a separate genotype for this hepatotropic virus. [ABSTRACT FROM AUTHOR]

Published
2010
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35. Distribución, movimientos y tamaño de grupo del tursión (Tursiops truncatus) al sur de Bahía San Quintín, Baja California, México.

Author

Morteo, E., Heckel, G., Defran, R. H., and Schramm, Y.

Subjects
*ZOOGEOGRAPHY, *POPULATION biology, *ECOLOGY, *BOTTLENOSE dolphin, *BAYS
Abstract

Twelve boat-based photoidentification surveys were carried out along the coast to the south of San Quintín Bay, in Baja California, Mexico, from July 1999 to June 2000; effort was 276.76 km and 31.7 h at sea. Twenty-two schools were encountered and 12.9 h of total observation were spent with 242 dolphins in these schools. The average school size was 11 (SD = 8) dolphins, although it is possible that groups are actually smaller; nursing groups were significantly larger (P < 0.05), with frequent membership exchanges occurring among schools. Dolphins preferred a coastal strip between 250 and 500 m offshore (P < 0.05), at depths below 7 m, and with sandy substrates (P < 0.05). Greater sighting frequencies occurred in two coastal zones (P < 0.05) and feeding was common around the mouth of the bay. Dorsal fin photographs led to the identification of 169 dolphins, and 124 were different individuals. During the study period, the coast south of San Quintín was a pass zone for transient dolphins, since most of the animals (>70%) were sighted one time or stayed for short periods. A total of 220 different dolphins have been identified in the San Quintín area when these data are combined with those gathered by Caldwell (1992) in 1990; these dolphins probably represent a small part of a larger population. More research on the population biology of the bottlenose dolphin in this and adjacent geographic areas is needed to develop better conservation and management strategies for this important natural resource. [ABSTRACT FROM AUTHOR]

Published
2004

37. BLOOD PLASMA PROTEINS AS INFLUENCED BY INTRAVENOUS INJECTION OF GUM ACACIA

Author

Heckel, G. P., Erickson, C. C., Yuile, C. L., and Knutti, R. E.

Abstract

Lowered plasma protein concentration following single injections of gum acacia in the dog is due in some part to dilution, and in greater part to actual decrease in total circulating protein. The maximum decrease in the total circulating protein does not take place at the same time as the maximum decrease in concentration. Fluctuations in fibrinogen concentration are marked, and are not necessarily proportional to changes in plasma protein concentration. Plasma protein concentration returns to normal limits within 10 to 21 days after the injection, at which time total circulating protein and plasma volume are lower than normal. Loss of protein cannot be accounted for by increase in urinary nitrogen. It is possible to maintain dogs at low levels of plasma protein concentration for several weeks by repeated injections of gum acacia solution. Anatomical changes following such a procedure in a normal dog are most conspicuous in the liver (Fig. A). These observations further implicate the liver as a source of plasma protein. Two mechanisms for the diminution of plasma protein following gum injection are suggested. One of these is based on the possibility that the liver cells being engorged with gum acacia are not able to produce the necessary amount of plasma protein to supply the normal demand. The other possibility is that with the injection of the gum, since there is obviously a greatly increased amount of colloid in the blood, the more readily removable colloid, i.e. plasma protein, is taken out of the blood stream, in an attempt to return plasma volume and colloid osmotic pressure to the normal limits. It is probable that both of these mechanisms are involved. Injection of gum acacia is suggested as a technique for further study of disturbed liver function. It must be obvious that clinical use of gum acacia for intravenous injection is not without danger.

Published
1938
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42. Ancient DNA reveals interstadials as a driver of common vole population dynamics during the last glacial period

Author

Baca, M., Popović, D., Lemanik, A., Bañuls-Cardona, S., Conard, N. J., Cuenca-Bescós, G., Desclaux, E., Fewlass, H., Garcia, J. T., Hadravova, T., Heckel, G., Horáček, I., Knul, M. V., Lebreton, L., López-García, J. M., Luzi, E., Marković, Z., Mauch Lenardić, J., Murelaga, X., Noiret, P., Petculescu, A., Popov, V., Rhodes, S. E., Ridush, B., Royer, A., Stewart, John R., Stojak, J., Talamo, S., Wang, X., Wójcik, J. M., Nadachowski, A., Baca, M., Popović, D., Lemanik, A., Bañuls-Cardona, S., Conard, N. J., Cuenca-Bescós, G., Desclaux, E., Fewlass, H., Garcia, J. T., Hadravova, T., Heckel, G., Horáček, I., Knul, M. V., Lebreton, L., López-García, J. M., Luzi, E., Marković, Z., Mauch Lenardić, J., Murelaga, X., Noiret, P., Petculescu, A., Popov, V., Rhodes, S. E., Ridush, B., Royer, A., Stewart, John R., Stojak, J., Talamo, S., Wang, X., Wójcik, J. M., and Nadachowski, A.

Abstract

Aim: Many species experienced population turnover and local extinction during the Late Pleistocene. In the case of megafauna, it remains challenging to disentangle climate change and the activities of Palaeolithic hunter-gatherers as the main cause. In contrast, the impact of humans on rodent populations is likely to be negligible. This study investigated which climatic and/or environmental factors affect the population dynamics of the common vole. This temperate rodent is widespread across Europe and was one of the most abundant small mammal species throughout the Late Pleistocene. Location: Europe. Taxon: Common vole (Microtus arvalis). Methods: We generated a dataset comprised of 4.2 kb long fragment of mitochondrial DNA (mtDNA) from 148 ancient and 51 modern specimens sampled from multiple localities across Europe and covering the last 60 thousand years (ka). We used Bayesian inference to reconstruct their phylogenetic relationships and to estimate the age of the specimens that were not directly dated. Results: We estimated the time to the most recent common ancestor of all last glacial and extant common vole lineages to be 90 ka ago and the divergence of the main mtDNA lineages present in extant populations to between 55 and 40 ka ago, which is earlier than most previous estimates. We detected several lineage turnovers in Europe during the period of high climate variability at the end of Marine Isotope Stage 3 (MIS 3; 57–29 ka ago) in addition to those found previously around the Pleistocene/Holocene transition. In contrast, data from the Western Carpathians suggest continuity throughout the Last Glacial Maximum (LGM) even at high latitudes. Main Conclusions: The main factor affecting the common vole populations during the last glacial period was the decrease in open habitat during the interstadials, whereas climate deterioration during the LGM had little impact on population dynamics. This suggests that the rapid environmental change rather than other factors

43. Static and Dynamic Strength Properties of a Fiber-Reinforced Compacted Cohesive Soil

Author

AI Wahab, R. M., Heckel, G. B., AI Wahab, R. M., and Heckel, G. B.

Abstract

Soil reinforcement with randomly oriented, individual synthetic fibers has been applied to laboratory specimens of a compacted cohesive soil. Fiber contents of up to 1.0% by soil dry weight were mixed with the soil. Data from unconfined compression (static) testing and resilient modulus (dynamic) testing have been presented. Experimental work showed that the fibers increased the soil unconfined compressive strength, ductility, toughness, static and dynamic energy absorption capacities, the resilient strain and the number of cycles to failure. The soil resilient modulus and the permanent strain both decreased with the increase in fiber content.

47. High variability and non-neutral evolution of the mammalian avpr1a gene

Author

Heckel Gerald, Excoffier Laurent, and Fink Sabine

Subjects
Evolution, QH359-425
Abstract

Abstract Background The arginine-vasopressin 1a receptor has been identified as a key determinant for social behaviour in Microtus voles, humans and other mammals. Nevertheless, the genetic bases of complex phenotypic traits like differences in social and mating behaviour among species and individuals remain largely unknown. Contrary to previous studies focusing on differences in the promotor region of the gene, we investigate here the level of functional variation in the coding region (exon 1) of this locus. Results We detected high sequence diversity between higher mammalian taxa as well as between species of the genus Microtus. This includes length variation and radical amino acid changes, as well as the presence of distinct protein variants within individuals. Additionally, negative selection prevails on most parts of the first exon of the arginine-vasopressin receptor 1a (avpr1a) gene but it contains regions with higher rates of change that harbour positively selected sites. Synonymous and non-synonymous substitution rates in the avpr1a gene are not exceptional compared to other genes, but they exceed those found in related hormone receptors with similar functions. Discussion These results stress the importance of considering variation in the coding sequence of avpr1a in regards to associations with life history traits (e.g. social behaviour, mating system, habitat requirements) of voles, other mammals and humans in particular.

Published
2007
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49. Genomes of Microtus Rodents Highlight the Importance of Olfactory and Immune Systems in Their Fast Radiation.

Author

Gouy A, Wang X, Kapopoulou A, Neuenschwander S, Schmid E, Excoffier L, and Heckel G

Subjects
Animals, Smell genetics, Evolution, Molecular, Phylogeny, Receptors, Odorant genetics, Immune System, Genetic Speciation, Arvicolinae genetics, Genome
Abstract

The characterization of genes and biological functions underlying functional diversification and the formation of species is a major goal of evolutionary biology. In this study, we investigated the fast radiation of Microtus voles, one of the most speciose group of mammals, which shows strong genetic divergence despite few readily observable morphological differences. We produced an annotated reference genome for the common vole, Microtus arvalis, and resequenced the genomes of 10 different species and evolutionary lineages spanning the Microtus speciation continuum. Our full-genome sequences illustrate the recent and fast diversification of this group, and we identified genes in highly divergent genomic windows that have likely particular roles in their radiation. We found three biological functions enriched for highly divergent genes in most Microtus species and lineages: olfaction, immunity and metabolism. In particular, olfaction-related genes (mostly olfactory receptors and vomeronasal receptors) are fast evolving in all Microtus species indicating the exceptional importance of the olfactory system in the evolution of these rodents. Of note is e.g. the shared signature among vole species on Olfr1019 which has been associated with fear responses against predator odors in rodents. Our analyses provide a genome-wide basis for the further characterization of the ecological factors and processes of natural and sexual selection that have contributed to the fast radiation of Microtus voles., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

Published
2024
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50. Genome-wide relaxation of selection and the evolution of the island syndrome in Orkney voles.

Author

Wang X and Heckel G

Subjects
Animals, Genetic Drift, Genome, Scotland, Genetic Variation, Arvicolinae genetics, Selection, Genetic, Islands, Evolution, Molecular
Abstract

Island populations often experience different ecological and demographic conditions than their counterparts on the continent, resulting in divergent evolutionary forces affecting their genomes. Random genetic drift and selection both may leave their imprints on island populations, although the relative impact depends strongly on the specific conditions. Here we address their contributions to the island syndrome in a rodent with an unusually clear history of isolation. Common voles ( Microtus arvalis ) were introduced by humans on the Orkney archipelago north of Scotland >5000 years ago and rapidly evolved to exceptionally large size. Our analyses show that the genomes of Orkney voles were dominated by genetic drift, with extremely low diversity, variable Tajima's D , and very high divergence from continental conspecifics. Increased d N / d S ratios over a wide range of genes in Orkney voles indicated genome-wide relaxation of purifying selection. We found evidence of hard sweeps on key genes of the lipid metabolism pathway only in continental voles. The marked increase of body size in Orkney-a typical phenomenon of the island syndrome-may thus be associated to the relaxation of positive selection on genes related to this pathway. On the other hand, a hard sweep on immune genes of Orkney voles likely reflects the divergent ecological conditions and possibly the history of human introduction. The long-term isolated Orkney voles show that adaptive changes may still impact the evolutionary trajectories of such populations despite the pervasive consequences of genetic drift at the genome level., (© 2024 Wang and Heckel; Published by Cold Spring Harbor Laboratory Press.)

Published
2024
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