TY - JOUR A1 - Wacker, Alexander A1 - Martin-Creuzburg, Dominik T1 - Biochemical nutrient requirements of the rotifer Brachionus calyciflorus co-limitation by sterols and amino acids JF - Functional ecology : an official journal of the British Ecological Society N2 - It has been proposed that growth and reproduction of animals is frequently limited by multiple nutrients simultaneously. To improve our understanding of the consequences of multiple nutrient limitations (i.e. co-limitation) for the performance of animals, we conducted standardized population growth experiments using an important aquatic consumer, the rotifer Brachionus calyciflorus. We compared nutrient profiles (sterols, fatty acids and amino acids) of rotifers and their diets to reveal consumerdiet imbalances and thus potentially limiting nutrients. In concomitant growth experiments, we directly supplemented potentially limiting substances (sterols, fatty acids, amino acids) to a nutrient-deficient diet, the cyanobacterium Synechococcus elongatus, and recorded population growth rates. The results from the supplementation experiments corroborated the nutrient limitations predicted by assessing consumerdiet imbalances, but provided more detailed information on co-limiting nutrients. While the fatty acid deficiency of the cyanobacterium appeared to be of minor importance, the addition of both cholesterol and certain amino acids (leucine and isoleucine) improved population growth rates of rotifers, indicating a simultaneous limitation by sterols and amino acids. Our results add to growing evidence that consumers frequently face multiple nutrient limitations and suggest that the concept of co-limitation has to be considered in studies assessing nutrient-limited growth responses of consumers. KW - consumer KW - consumer-diet imbalance KW - dietary mismatch KW - fatty acid KW - global change KW - lipid KW - nutrition KW - phytoplankton KW - tetrahymanol KW - zooplankton Y1 - 2012 U6 - https://doi.org/10.1111/j.1365-2435.2012.02047.x SN - 0269-8463 VL - 26 IS - 5 SP - 1135 EP - 1143 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Martin-Creuzburg, Dominik A1 - Sperfeld, Erik A1 - Wacker, Alexander T1 - Colimitation of a freshwater herbivore by sterols and polyunsaturated fatty acids N2 - Empirical data providing evidence for a colimitation of an herbivore by two or more essential nutrients are scarce, particularly in regard to biochemical resources. Here, a graphical model is presented, which describes the growth of an herbivore in a system with two potentially limiting resources. To verify this model, life-history experiments were conducted with the herbivore Daphnia magna feeding on the picocyanobacterium Synechococcus elongatus, which was supplemented with increasing amounts of cholesterol either in the presence or the absence of saturating amounts of eicosapentaenoic acid (EPA). For comparison, D. magna was raised on diets containing different proportions of S. elongatus and the cholesterol- and EPA-rich eukaryotic alga Nannochloropsis limnetica. Somatic and population growth of D. magna on a sterol- and EPA-deficient diet was initially constrained by the absence of sterols. With increased sterol availability, a colimitation by EPA became apparent and when the sterol requirements were met, the growth- limiting factor was shifted from a limitation by sterols to a limitation by EPA. These data imply that herbivores are frequently limited by two or more essential nutrients simultaneously. Hence, the concept of colimitation has to be incorporated into models assessing nutrient-limited growth kinetics of herbivores to accurately predict demographic changes and population dynamics. Y1 - 2009 UR - http://rspb.royalsocietypublishing.org/content/by/year U6 - https://doi.org/10.1098/rspb.2008.1540 SN - 0962-8452 ER - TY - JOUR A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander A1 - Ziese, Christine A1 - Kainz, Martin J. T1 - Dietary lipid quality affects temperature-mediated reaction norms of a freshwater key herbivore JF - Oecologia N2 - Temperature-mediated plasticity in life history traits strongly affects the capability of ectotherms to cope with changing environmental temperatures. We hypothesised that temperature-mediated reaction norms of ectotherms are constrained by the availability of essential dietary lipids, i.e. polyunsaturated fatty acids (PUFA) and sterols, as these lipids are involved in the homeoviscous adaptation of biological membranes to changing temperatures. A life history experiment was conducted in which the freshwater herbivore Daphnia magna was raised at four different temperatures (10, 15, 20, 25A degrees C) with food sources differing in their PUFA and sterol composition. Somatic growth rates increased significantly with increasing temperature, but differences among food sources were obtained only at 10A degrees C at which animals grew better on PUFA-rich diets than on PUFA-deficient diets. PUFA-rich food sources resulted in significantly higher population growth rates at 10A degrees C than PUFA-deficient food, and the optimum temperature for offspring production was clearly shifted towards colder temperatures with an increased availability of dietary PUFA. Supplementation of PUFA-deficient food with single PUFA enabled the production of viable offspring and significantly increased population growth rates at 10A degrees C, indicating that dietary PUFA are crucial for the acclimation to cold temperatures. In contrast, cumulative numbers of viable offspring increased significantly upon cholesterol supplementation at 25A degrees C and the optimum temperature for offspring production was shifted towards warmer temperatures, implying that sterol requirements increase with temperature. In conclusion, essential dietary lipids significantly affect temperature-mediated reaction norms of ectotherms and thus temperature-mediated plasticity in life history traits is subject to strong food quality constraints. KW - Daphnia KW - Food quality KW - Phenotypic plasticity KW - Polyunsaturated fatty acids KW - Sterols Y1 - 2012 U6 - https://doi.org/10.1007/s00442-011-2155-1 SN - 0029-8549 VL - 168 IS - 4 SP - 901 EP - 912 PB - Springer CY - New York ER - TY - GEN A1 - Schälicke, Svenja A1 - Teubner, Johannes A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander T1 - Fitness response variation within and among consumer species can be co-mediated by food quantity and biochemical quality T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - In natural heterogeneous environments, the fitness of animals is strongly influenced by the availability and composition of food. Food quantity and biochemical quality constraints may affect individual traits of consumers differently, mediating fitness response variation within and among species. Using a multifactorial experimental approach, we assessed population growth rate, fecundity, and survival of six strains of the two closely related freshwater rotifer species Brachionus calyciflorus sensu stricto and Brachionus fernandoi. Therefore, rotifers fed low and high concentrations of three algal species differing in their biochemical food quality. Additionally, we explored the potential of a single limiting biochemical nutrient to mediate variations in population growth response. Therefore, rotifers fed a sterol-free alga, which we supplemented with cholesterol-containing liposomes. Co-limitation by food quantity and biochemical food quality resulted in differences in population growth rates among strains, but not between species, although effects on fecundity and survival differed between species. The effect of cholesterol supplementation on population growth was strain-specific but not species-specific. We show that fitness response variations within and among species can be mediated by biochemical food quality. Dietary constraints thus may act as evolutionary drivers on physiological traits of consumers, which may have strong implications for various ecological interactions. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 806 KW - Polyunsaturated Fatty-Acids KW - Life-History Consequences KW - 2 Different Strains KW - Population-Growth KW - Resource Competition KW - Body-Size KW - Egg Size KW - Rotifier KW - Limitation KW - Carbon Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-442256 SN - 1866-8372 IS - 806 ER - TY - JOUR A1 - Schälicke, Svenja A1 - Teubner, Johannes A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander T1 - Fitness response variation within and among consumer species can be co-mediated by food quantity and biochemical quality JF - Scientific Reports N2 - In natural heterogeneous environments, the fitness of animals is strongly influenced by the availability and composition of food. Food quantity and biochemical quality constraints may affect individual traits of consumers differently, mediating fitness response variation within and among species. Using a multifactorial experimental approach, we assessed population growth rate, fecundity, and survival of six strains of the two closely related freshwater rotifer species Brachionus calyciflorus sensu stricto and Brachionus fernandoi. Therefore, rotifers fed low and high concentrations of three algal species differing in their biochemical food quality. Additionally, we explored the potential of a single limiting biochemical nutrient to mediate variations in population growth response. Therefore, rotifers fed a sterol-free alga, which we supplemented with cholesterol-containing liposomes. Co-limitation by food quantity and biochemical food quality resulted in differences in population growth rates among strains, but not between species, although effects on fecundity and survival differed between species. The effect of cholesterol supplementation on population growth was strain-specific but not species-specific. We show that fitness response variations within and among species can be mediated by biochemical food quality. Dietary constraints thus may act as evolutionary drivers on physiological traits of consumers, which may have strong implications for various ecological interactions. KW - Polyunsaturated Fatty-Acids KW - Life-History Consequences KW - 2 Different Strains KW - Population-Growth KW - Resource Competition KW - Body-Size KW - Egg Size KW - Rotifier KW - Limitation KW - Carbon Y1 - 2019 U6 - https://doi.org/10.1038/s41598-019-52538-2 SN - 2045-2322 VL - 9 PB - Macmillan Publishers Limited CY - London ER - TY - JOUR A1 - Schälicke, Svenja A1 - Sobisch, Lydia-Yasmin A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander T1 - Food quantity-quality co-limitation BT - interactive effects of dietary carbon and essential lipid supply on population growth of a freshwater rotifer JF - Freshwater biology N2 - Food quantity and quality are highly variable in natural systems. Therefore, their interplay and the associated effects on consumer population growth are important for predator-prey interactions and community dynamics. Experiments in which consumers were exposed to elemental nutrient limitations along food quantity gradients suggest that food quality effects on consumer performance are relevant only at high food quantities. However, elemental nutrients act differently on physiological processes than biochemical nutrients. So far, the interactive effects of food quantity and biochemical compounds on consumer performance have been insufficiently studied. We studied interactive effects of food quantity and biochemical food quality on population growth, including fecundity and survival, of the freshwater rotifer Brachionus calyciflorus. We hypothesised that these life history traits are differently affected by the availability of biochemical nutrients and that food quality effects gain importance with increasing food quantity. In a first experiment, we established food quantity and quality gradients by providing rotifers with different concentrations of a low-quality food, the sterol-free cyanobacterium Synechococcus elongatus, supplemented with increasing amounts of cholesterol. In a second experiment, food quantity and quality gradients were established by providing different proportions of two prey species differing in biochemical food quality, i.e. S.elongatus and the lipid-rich alga Nannochloropsis limnetica, at different total food concentrations. We found that the effects of cholesterol supplementation on population growth increased with increasing food quantity. This interactive effect on population growth was mainly due to food quality effects on fecundity, as effects on survival remained constant along the food quantity gradient. In contrast, when feeding on the mixed algal diet, the food quality effect associated with increasing the proportion of the high-quality alga did not change along the food quantity gradient. The data on survival and fecundity demonstrate the missing interactive effect of food quantity and quality on population growth, as both traits were oppositely affected. Survival was affected by food quality primarily at low food quantity, whereas food quality effects on fecundity were stronger at high food quantity. Our results highlight the significance of essential biochemicals in mediating the interactive effects of food quantity and quality on population growth. The interplay between food quantity and biochemical food quality limitation seems to influence resource allocation patterns in order to optimise survival or reproduction, which may strongly affect population dynamics in variable environments. As opposed to exploring the function of a single nutrient via supplementation, using algae mixtures allowed us to assess food quality effects on consumer performance in a more natural context by taking potential interactive effects of multiple co-limiting nutrients into account. KW - Brachionus calyciflorus KW - fecundity KW - population growth rate KW - sterols KW - survival Y1 - 2019 U6 - https://doi.org/10.1111/fwb.13272 SN - 0046-5070 SN - 1365-2427 VL - 64 IS - 5 SP - 903 EP - 912 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Schälicke, Svenja A1 - Heim, Silvia A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander T1 - Inter- and intraspecific differences in rotifer fatty acid composition during acclimation to low-quality food JF - Philosophical transactions of the Royal Society of London : B, Biological sciences N2 - Biochemical food quality constraints affect the performance of consumers and mediate trait variation among and within consumer species. To assess inter- and intraspecific differences in fatty acid retention and conversion in freshwater rotifers, we provided four strains of two closely related rotifer species,Brachionus calyciflorussensustricto andBrachionus fernandoi, with food algae differing in their fatty acid composition. The rotifers grazed for 5 days on eitherNannochloropsis limneticaorMonoraphidium minutum, two food algae with distinct polyunsaturated fatty acid (PUFA) profiles, before the diets were switched to PUFA-freeSynechococcus elongatus, which was provided for three more days. We found between- and within-species differences in rotifer fatty acid compositions on the respective food sources and, in particular, highly specific acclimation reactions to the PUFA-free diet. The different reactions indicate inter- but also intraspecific differences in physiological traits, such as PUFA retention, allocation and bioconversion capacities, within the genusBrachionusthat are most likely accompanied by differences in their nutritional demands. Our data suggest that biochemical food quality constraints act differently on traits of closely related species and of strains of a particular species and thus might be involved in shaping ecological interactions and evolutionary processes. This article is part of the theme issue 'The next horizons for lipids as 'trophic biomarkers': evidence and significance of consumer modification of dietary fatty acids'. KW - Brachionus KW - fatty acids KW - food quality KW - PUFA composition KW - rotifer KW - strains KW - trait variation Y1 - 2020 U6 - https://doi.org/10.1098/rstb.2019.0644 SN - 0962-8436 SN - 1471-2970 VL - 375 IS - 1804 PB - Royal Society CY - London ER - TY - JOUR A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander A1 - von Elert, Eric T1 - Life history consequences of sterol availability in the aquatic keystone species Daphnia N2 - The absence of essential biochemical nutrients, such as polyunsaturated fatty acids or sterols, has been considered as a mechanism determining trophic interactions between the herbivore Daphnia and its phytoplankton food source. Here, we experimentally quantify the sensitivity of two Daphnia species to decreasing amounts of dietary sterols by measuring variations in life history traits. The two species Daphnia magna and D. galeata were fed different mixtures of the sterol-containing green alga Scenedesmus obliquus and the sterol-free cyanobacterium Synechococcus elongatus; a higher proportion of Synechococcus in the food is equivalent to a decrease in dietary sterols. To address the significance of sterol limitation, the Daphnia species were also fed Synechococcus supplemented with cholesterol. In both species, somatic and population growth rates, maternal dry mass, the number of viable offspring, and the probability of survival were significantly reduced with the lower availability of sterols. A high correlation between the sterol content of the mixed diet and the somatic and population growth rates was found, and growth on cholesterol- supplemented Synechococcus fitted well into this correlation. Somatic growth of first-clutch neonates grown on 100% Synechococcus exhibited a pattern similar to that of somatic growth of their mothers grown on the different food regimes, which demonstrated the significance of maternal effects for sterol-limited population growth. Daphnia galeata had a twofold higher incipient limiting sterol level than D. magna, which indicated interspecific differences in sterol requirements between the two Daphnia species. The results suggest a strong impact of dietary sterols on life history traits and therefore, population dynamics of the keystone species Daphnia Y1 - 2005 SN - 0029-8549 ER - TY - JOUR A1 - Marzetz, Vanessa A1 - Koussoroplis, Apostolos-Manuel A1 - Martin-Creuzburg, Dominik A1 - Striebel, Maren A1 - Wacker, Alexander T1 - Linking primary producer diversity and food quality effects on herbivores: A biochemical perspective JF - Scientific reports N2 - Biodiversity can strongly influence trophic interactions. The nutritional quality of prey communities and how it is related to the prey diversity is suspected to be a major driver of biodiversity effects. As consumer growth can be co-limited by the supply of several biochemical components, biochemically diverse prey communities should promote consumer growth. Yet, there is no clear consensus on how prey specific diversity is linked to community biochemical diversity since previous studies have considered only single nutritional quality traits. Here, we demonstrate that phytoplankton biochemical traits (fatty acids and sterols) can to a large extent explain Daphnia magna growth and its apparent dependence on phytoplankton species diversity. We find strong correlative evidence between phytoplankton species diversity, biochemical diversity, and growth. The relationship between species diversity and growth was partially explained by the fact that in many communities Daphnia was co-limited by long chained polyunsaturated fatty acids and sterols, which was driven by different prey taxa. We suggest that biochemical diversity is a good proxy for the presence of high food quality taxa, and a careful consideration of the distribution of the different biochemical traits among species is necessary before concluding about causal links between species diversity and consumer performance. Y1 - 2017 U6 - https://doi.org/10.1038/s41598-017-11183-3 SN - 2045-2322 VL - 7 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Sperfeld, Erik A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander T1 - Multiple resource limitation theory applied to herbivorous consumers Liebig's minimum rule vs. interactive co-limitation JF - Ecology letters N2 - There is growing consensus that the growth of herbivorous consumers is frequently limited by more than one nutrient simultaneously. This understanding, however, is based primarily on theoretical considerations and the applicability of existing concepts of co-limitation has rarely been tested experimentally. Here, we assessed the suitability of two contrasting concepts of resource limitation, i.e. Liebigs minimum rule and the multiple limitation hypothesis, to describe nutrient-dependent growth responses of a freshwater herbivore (Daphnia magna) in a system with two potentially limiting nutrients (cholesterol and eicosapentaenoic acid). The results indicated that these essential nutrients interact, and do not strictly follow Liebigs minimum rule, which consistently overestimates growth at co-limiting conditions and thus is not applicable to describe multiple nutrient limitation of herbivorous consumers. We infer that the outcome of resource-based modelling approaches assessing herbivore population dynamics strongly depends on the applied concept of co-limitation. KW - Cholesterol KW - Daphnia magna KW - eicosapentaenoic acid KW - essential resources KW - food quality KW - herbivore KW - multi-nutrient limitation KW - nutritional ecology KW - von Liebig Y1 - 2012 U6 - https://doi.org/10.1111/j.1461-0248.2011.01719.x SN - 1461-023X VL - 15 IS - 2 SP - 142 EP - 150 PB - Wiley-Blackwell CY - Malden ER -