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7. Raw material procurement for termite fishing tools by wild chimpanzees in the Issa valley, Western Tanzania

Author

Almeida-Warren, K, Sommer, V, Piel, AK, and Pascual-Garrido, A

Subjects
Pan troglodytes, Tool Use Behavior, Plant Bark, Animals, Feeding Behavior, Isoptera, Plants, Tanzania, Anthropology, Physical
Abstract

Objectives Chimpanzee termite fishing has been studied for decades, yet the selective processes preceding the manufacture of fishing tools remain largely unexplored. We investigate raw material selection and potential evidence of forward planning in the chimpanzees of Issa valley, western Tanzania. Materials and Methods Using traditional archaeological methods, we surveyed the location of plants from where chimpanzees sourced raw material to manufacture termite fishing tools, relative to targeted mounds. We measured raw material abundance to test for availability and selection. Statistics included Chi‐Squared, two‐tailed Wilcoxon, and Kruskall–Wallace tests. Results Issa chimpanzees manufactured extraction tools only from bark, despite availability of other suitable materials (e.g., twigs), and selected particular plant species as raw material sources, which they often also exploit for food. Most plants were sourced 1–16 m away from the mound, with a maximum of 33 m. The line of sight from the targeted mound was obscured for a quarter of these plants. Discussion The exclusive use of bark tools despite availability of other suitable materials indicates a possible cultural preference. The fact that Issa chimpanzees select specific plant species and travel some distance to source them suggests some degree of selectivity and, potentially, forward planning. Our results have implications for the reconstruction of early hominin behaviors, particularly with regard to the use of perishable tools, which remain archaeologically invisible.

Published
2021

9. Biological soil crusts on the Zielitz tailings pile cover.

Author

Sommer V., Gose N., Karsten U., Kockx M., Schmeisky A., Wolk A., Sommer V., Gose N., Karsten U., Kockx M., Schmeisky A., and Wolk A.

Abstract

The covering of potash tailings piles aims at minimising the rain induced brine formation. At the Zielitz site a new covering technique – the infiltration barrier system (IHS) – was developed. By adding insoluble compounds to the top layer of the tailings the water storage capacity and therefore the evaporation rate is improved. During field trials the growth of various photosynthetic active microorganisms and even small plants could be observed. These biological soil crusts can improve the evaporation rates at the surface, contribute to their stability and in the long term lead to soil formation, which finally facilitates settlement by higher plants. (Authors.), The covering of potash tailings piles aims at minimising the rain induced brine formation. At the Zielitz site a new covering technique – the infiltration barrier system (IHS) – was developed. By adding insoluble compounds to the top layer of the tailings the water storage capacity and therefore the evaporation rate is improved. During field trials the growth of various photosynthetic active microorganisms and even small plants could be observed. These biological soil crusts can improve the evaporation rates at the surface, contribute to their stability and in the long term lead to soil formation, which finally facilitates settlement by higher plants. (Authors.)

Published
2021

10. Structure of chimpanzee gut microbiomes across tropical Africa

Author

Bueno de Mesquita, C.P., Nichols, L.M., Gebert, M.J., Vanderburgh, C., Bocksberger, G., Lester, J.D., Kalan, A.K., Dieguez, P., McCarthy, M.S., Agbor, A., Álvarez Varona, P., Ayimisin, A.E., Bessone, M., Chancellor, R., Cohen, H., Coupland, C., Deschner, T., Egbe, V.E., Goedmakers, A., Granjon, A.-C., Grueter, C.C., Head, J., Hernandez-Aguilar, R.A., Jeffery, K.J., Jones, S., Kadam, P., Kaiser, M., Lapuente, J., Larson, B., Marrocoli, S., Morgan, D., Mugerwa, B., Mulindahabi, F., Neil, E., Niyigaba, P., Pacheco, L., Piel, A.K., Robbins, M.M., Rundus, A., Sanz, C.M., Sciaky, L., Sheil, D., Sommer, V., Stewart, F.A., Ton, E., van Schijndel, J., Vergnes, V., Wessling, E.G., Wittig, R.M., Ginath Yuh, Y., Yurkiw, K., Zuberbühler, K., Gogarten, J.F., Heintz-Buschart, Anna, Muellner-Riehl, A.N., Boesch, C., Kühl, H.S., Fierer, N., Arandjelovic, M., Dunn, R.R., Bueno de Mesquita, C.P., Nichols, L.M., Gebert, M.J., Vanderburgh, C., Bocksberger, G., Lester, J.D., Kalan, A.K., Dieguez, P., McCarthy, M.S., Agbor, A., Álvarez Varona, P., Ayimisin, A.E., Bessone, M., Chancellor, R., Cohen, H., Coupland, C., Deschner, T., Egbe, V.E., Goedmakers, A., Granjon, A.-C., Grueter, C.C., Head, J., Hernandez-Aguilar, R.A., Jeffery, K.J., Jones, S., Kadam, P., Kaiser, M., Lapuente, J., Larson, B., Marrocoli, S., Morgan, D., Mugerwa, B., Mulindahabi, F., Neil, E., Niyigaba, P., Pacheco, L., Piel, A.K., Robbins, M.M., Rundus, A., Sanz, C.M., Sciaky, L., Sheil, D., Sommer, V., Stewart, F.A., Ton, E., van Schijndel, J., Vergnes, V., Wessling, E.G., Wittig, R.M., Ginath Yuh, Y., Yurkiw, K., Zuberbühler, K., Gogarten, J.F., Heintz-Buschart, Anna, Muellner-Riehl, A.N., Boesch, C., Kühl, H.S., Fierer, N., Arandjelovic, M., and Dunn, R.R.

Abstract

Understanding variation in host-associated microbial communities is important given the relevance of microbiomes to host physiology and health. Using 560 fecal samples collected from wild chimpanzees (Pan troglodytes) across their range, we assessed how geography, genetics, climate, vegetation, and diet relate to gut microbial community structure (prokaryotes, eukaryotic parasites) at multiple spatial scales. We observed a high degree of regional specificity in the microbiome composition, which was associated with host genetics, available plant foods, and potentially with cultural differences in tool use, which affect diet. Genetic differences drove community composition at large scales, while vegetation and potentially tool use drove within-region differences, likely due to their influence on diet. Unlike industrialized human populations in the United States, where regional differences in the gut microbiome are undetectable, chimpanzee gut microbiomes are far more variable across space, suggesting that technological developments have decoupled humans from their local environments, obscuring regional differences that could have been important during human evolution.

Published
2021

14. Patient Selection for Hepatocellular Carcinoma Resection in Child a Cirrhosis Can Be Limited by Disease Presentation at Safety Net Hospitals vs Academic Centers

Author

Vitiello, Gerardo A., primary, Lee, Rachel M., additional, Russell, Maria Citarella, additional, Charles Yopp, Adam, additional, Ryon, Emily Leah, additional, Goel, Neha, additional, Luu, Sommer V., additional, Hsu, Cary, additional, Silberfein, Eric Jay, additional, and Lee, Ann Y., additional

Published
2020
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25. Reversibility of exercise-induced translocation of Na+-K+ pump subunits to the plasma membrane in rat skeletal muscle

Author

Juel, C, Grunnet, L, Holse, M, Kenworthy, S, Sommer, V, Wulff, T, Juel, C, Grunnet, L, Holse, M, Kenworthy, S, Sommer, V, and Wulff, T

Abstract

Exercise-induced translocation of Na+-K+ pump subunits to the sarcolemmal membrane was studied using sarcolemmal giant vesicles as a membrane purification procedure. The subunit content was quantified by Western blotting or by ouabain labeling. Low-intensity treadmill running increased (P<0.01) the alpha1, alpha2, beta1, and beta2 subunit contents by 19-32% in membranes from oxidative muscle fibers and the alpha1, alpha2, and beta2 contents increased by 13-25% in membranes from glycolytic muscle fibers. Ouabain labeling of membranes from mixed fibers was increased by 29% after exercise. A similar increase in subunit content could be induced by 5 min of fatiguing, high-intensity electrical stimulation of isolated soleus muscles. An increased subunit content was just detectable in vesicles produced 30 min after exercise, and the content was completely back to control levels 3 h after exercise. It is concluded that both low-intensity long-lasting running and short-lasting high-intensity contractions are able to induce a translocation of pump subunits to the sarcolemmal membrane. The post-exercise disappearance of the extra subunits (half-time approximately 20 min) from the membrane demonstrates the reversible nature of the translocation process.

Published
2001

33. The TD-CDMA based UTRA TDD mode

Author

Haardt, M., primary, Klein, A., additional, Koehn, R., additional, Oestreich, S., additional, Purat, M., additional, Sommer, V., additional, and Ulrich, T., additional

Published
2000
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48. Army ant prey availability and consumption by chimpanzees ( Pan troglodytes vellerosus) at Gashaka (Nigeria).

Author

Schöning, C., Ellis, D., Fowler, A., and Sommer, V.

Subjects
ARMY ants, ANTS, CHIMPANZEES, ANIMAL nutrition, ECOLOGY
Abstract

Army ant predation by chimpanzees has been studied as an intriguing example of tool use and a possible case of cultural variation. However, the importance of army ant prey in chimpanzee diet and feeding ecology is still only poorly understood. We studied the availability and consumption of army ants in a population of the chimpanzee subspecies Pan troglodytes vellerosus in Nigeria. Army ants were collected from nests and trails (workers) and near artificial light sources (males). Three potential prey species were found: Dorylus rufescens, Dorylus gerstaeckeri and Dorylus kohli. Dorylus rufescens was by far more abundant than the other two species. Only remains from D. rufescens were present in chimpanzee faeces. This is the first report of consumption of this ant species by chimpanzees. However, because of the low availability of the other two species, it is unclear whether this pattern reflects a preference for D. rufescens. Although D. rufescens' availability varied with weather conditions, the occurrence as well as the absolute and relative numbers of Dorylus fragments in faeces did not. This finding, together with the considerable difficulties encountered by human observers in their efforts to locate nests by following trails, suggests that the chimpanzees in this population do not harvest army ants from trails and do not use trails to locate nests. The overall occurrence of army ant fragments in 42.3% of all faecal samples is the highest ever recorded in any chimpanzee population. This indicates that in this chimpanzee population, army ant prey is not a fallback during periods of sparse availability of plant food, but quantitatively important throughout the year. Future studies will be needed to clarify which cues and strategies chimpanzees use to locate army ant nests and to assess the role of myrmecophagy with respect to macro- or micronutrient demands. [ABSTRACT FROM AUTHOR]

Published
2007
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