@article{KoussoroplisWacker2016, author = {Koussoroplis, Apostolos-Manuel and Wacker, Alexander}, title = {Covariance modulates the effect of joint temperature and food variance on ectotherm life-history traits}, series = {Ecology letters}, volume = {19}, journal = {Ecology letters}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1461-023X}, doi = {10.1111/ele.12546}, pages = {143 -- 152}, year = {2016}, abstract = {Understanding animal performance in heterogeneous or variable environments is a central question in ecology. We combine modelling and experiments to test how temperature and food availability variance jointly affect life-history traits of ectotherms. The model predicts that as mean temperatures move away from the ectotherm's thermal optimum, the effect size of joint thermal and food variance should become increasingly sensitive to their covariance. Below the thermal optimum, performance should be positively correlated with food-temperature covariance and the opposite is predicted above it. At lower temperatures, covariance should determine whether food and temperature variance increases or decreases performance compared to constant conditions. Somewhat stronger than predicted, the covariance effect below the thermal optimum was confirmed experimentally on an aquatic ectotherm (Daphnia magna) exposed to diurnal food and temperature variance with different amounts of covariance. Our findings have important implications for understanding ectotherm responses to climate-driven alterations of thermal mean and variance.}, language = {en} } @misc{DeSouzaSilveiraCarlsohnLangenetal.2016, author = {De Souza Silveira, Raul and Carlsohn, Anja and Langen, Georg and Mayer, Frank and Scharhag-Rosenberger, Friederike}, title = {Reliability and day-to-day variability of peak fat oxidation during treadmill ergometry}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {423}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-407334}, pages = {7}, year = {2016}, abstract = {Background: Exercising at intensities where fat oxidation rates are high has been shown to induce metabolic benefits in recreational and health-oriented sportsmen. The exercise intensity (Fat peak ) eliciting peak fat oxidation rates is therefore of particular interest when aiming to prescribe exercise for the purpose of fat oxidation and related metabolic effects. Although running and walking are feasible and popular among the target population, no reliable protocols are available to assess Fat peak as well as its actual velocity (V PFO ) during treadmill ergometry. Our purpose was therefore, to assess the reliability and day-to-day variability of V PFO and Fat peak during treadmill ergometry running. Methods: Sixteen recreational athletes (f = 7, m = 9; 25 ± 3 y; 1.76 ± 0.09 m; 68.3 ± 13.7 kg; 23.1 ± 2.9 kg/m 2 ) performed 2 different running protocols on 3 different days with standardized nutrition the day before testing. At day 1, peak oxygen uptake (VO 2peak ) and the velocities at the aerobic threshold (V LT ) and respiratory exchange ratio (RER) of 1.00 (V RER ) were assessed. At days 2 and 3, subjects ran an identical submaximal incremental test (Fat-peak test) composed of a 10 min warm-up (70 \% V LT ) followed by 5 stages of 6 min with equal increments (stage 1 = V LT , stage 5 = V RER ). Breath-by-breath gas exchange data was measured continuously and used to determine fat oxidation rates. A third order polynomial function was used to identify V PFO and subsequently Fat peak . The reproducibility and variability of variables was verified with an int raclass correlation coef ficient (ICC), Pearson ' s correlation coefficient, coefficient of variation (CV) an d the mean differences (bias) ± 95 \% limits of agreement (LoA). Results: ICC, Pearson ' s correlation and CV for V PFO and Fat peak were 0.98, 0.97, 5.0 \%; and 0.90, 0.81, 7.0 \%, respectively. Bias ± 95 \% LoA was - 0.3 ± 0.9 km/h for V PFO and - 2±8\%ofVO 2peak for Fat peak. Conclusion: In summary, relative and absolute reliability indicators for V PFO and Fat peak were found to be excellent. The observed LoA may now serve as a basis for future training prescriptions, although fat oxidation rates at prolonged exercise bouts at this intensity still need to be investigated.}, language = {en} } @misc{CohenCampisanoArrowsmithetal.2016, author = {Cohen, Abby and Campisano, Christopher and Arrowsmith, J. Ramon and Asrat, Asfawossen and Behrensmeyer, A. K. and Deino, A. and Feibel, C. and Hill, A. and Johnson, R. and Kingston, J. and Lamb, Henry F. and Lowenstein, T. and Noren, A. and Olago, D. and Owen, Richard Bernhart and Potts, R. and Reed, Kate and Renaut, R. and Sch{\"a}bitz, F. and Tiercelin, J.-J. and Trauth, Martin H. and Wynn, J. and Ivory, S. and Brady, K. and O'Grady, R. and Rodysill, J. and Githiri, J. and Russell, Joellen and Foerster, Verena and Dommain, Ren{\´e} and Rucina, J. S. and Deocampo, D. and Russell, J. and Billingsley, A. and Beck, C. and Dorenbeck, G. and Dullo, L. and Feary, D. and Garello, D. and Gromig, R. and Johnson, T. and Junginger, Annett and Karanja, M. and Kimburi, E. and Mbuthia, A. and McCartney, Tannis and McNulty, E. and Muiruri, V. and Nambiro, E. and Negash, E. W. and Njagi, D. and Wilson, J. N. and Rabideaux, N. and Raub, Timothy and Sier, Mark Jan and Smith, P. and Urban, J. and Warren, M. and Yadeta, M. and Yost, Chad and Zinaye, B.}, title = {The Hominin Sites and Paleolakes Drilling Project}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {611}, doi = {10.25932/publishup-41249}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-412498}, pages = {16}, year = {2016}, abstract = {The role that climate and environmental history may have played in influencing human evolution has been the focus of considerable interest and controversy among paleoanthropologists for decades. Prior attempts to understand the environmental history side of this equation have centered around the study of outcrop sediments and fossils adjacent to where fossil hominins (ancestors or close relatives of modern humans) are found, or from the study of deep sea drill cores. However, outcrop sediments are often highly weathered and thus are unsuitable for some types of paleoclimatic records, and deep sea core records come from long distances away from the actual fossil and stone tool remains. The Hominin Sites and Paleolakes Drilling Project (HSPDP) was developed to address these issues. The project has focused its efforts on the eastern African Rift Valley, where much of the evidence for early hominins has been recovered. We have collected about 2 km of sediment drill core from six basins in Kenya and Ethiopia, in lake deposits immediately adjacent to important fossil hominin and archaeological sites. Collectively these cores cover in time many of the key transitions and critical intervals in human evolutionary history over the last 4 Ma, such as the earliest stone tools, the origin of our own genus Homo, and the earliest anatomically modern Homo sapiens. Here we document the initial field, physical property, and core description results of the 2012-2014 HSPDP coring campaign.}, language = {en} }