title: Developmental plasticity of growth and digestive efficiency in dependence of early-life food availability.
abstract: Nutrition is a potent mediator of developmental plasticity. If food is scarce, developing organisms may invest into growth to outgrow size-dependent mortality (short-term benefit) and/or into an efficient digestion system (long-term benefit). We investigated this potential trade-off, by determining the influence of food availability on juvenile body and organ growth, and on adult digestive efficiency in the cichlid fishSimochromis pleurospilus. We reared two groups of fish at constant high or low food rations, and we switched four other groups between these two rations at an early and late juvenile period. We measured juvenile growth and organ sizes at different developmental stages and determined adult digestive efficiency. Fish kept at constant, high rations grew considerably faster than low-food fish. Nevertheless,S. pleurospiluspartly buffered the negative effects of low food availability by developing heavier digestive organs, and they were therefore more efficient in digesting their food as adults. Results of fish exposed to a ration switch during either the early or late juvenile period suggest (i) that the ability to show compensatory growth after early exposure to low food availability persists during the juvenile period, (ii) that digestive efficiency is influenced by varying juvenile food availability during the late juvenile phase and (iii) that the efficiency of the adult digestive system is correlated with the growth rate during a narrow time window of juvenile period.
authors: Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen Switzerland ; Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, University of Veterinary Medicine Vienna Savoyenstraße 1a, Vienna, A-1160, Austria.
authors: Alexander
authors: A
authors: Kotrschal
authors: Department of Chemistry and Biochemistry, University of Bern Freiestraße 3, CH-3012 Bern, Switzerland.
authors: Sönke
authors: S
authors: Szidat
authors: Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Wohlenstrasse 50a, CH-3032 Hinterkappelen Switzerland.
authors: Barbara
authors: B
authors: Taborsky
keywords: Lake Tanganyika; cichlid fish; digestive efficiency; early environment; growth rate; phenotypic plasticity; plasticity window