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  - Koussoroplis, Apostolos-Manuel
A1  - Schälicke, Svenja
A1  - Raatz, Michael
A1  - Bach, Moritz
A1  - Wacker, Alexander
T1  - Feeding in the frequency domain
BT  - Coarser-grained environments increase consumer sensitivity to resource variability, covariance and phase
JF  - Ecology letters
N2  - Theory predicts that resource variability hinders consumer performance. How this effect depends on the temporal structure of resource fluctuations encountered by individuals remains poorly understood. Combining modelling and growth experiments with Daphnia magna, we decompose the complexity of resource fluctuations and test the effect of resource variance, supply peak timing (i.e. phase) and co-limiting resource covariance along a gradient from high to low frequencies reflecting fine- to coarse-grained environments. Our results show that resource storage can buffer growth at high frequencies, but yields a sensitivity of growth to resource peak timing at lower ones. When two resources covary, negative covariance causes stronger growth depression at low frequencies. However, negative covariance might be beneficial at intermediate frequencies, an effect that can be explained by digestive acclimation. Our study provides a mechanistic basis for understanding how alterations of the environmental grain size affect consumers experiencing variable nutritional quality in nature.
KW  - Cholesterol
KW  - covariance
KW  - Daphnia
KW  - digestive acclimation
KW  - dynamic energy budgets
KW  - food quality
KW  - phosphorus
KW  - storage
KW  - unbalanced diets
Y1  - 2019
U6  - https://doi.org/10.1111/ele.13267
SN  - 1461-023X
SN  - 1461-0248
VL  - 22
IS  - 7
SP  - 1104
EP  - 1114
PB  - Wiley
CY  - Hoboken
ER  -