Article

Effect of growth compensation on subsequent physical fitness in green swordtails Xiphophorus helleri.

Division of Environmental and Evolutionary Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK.
Biology letters (Impact Factor: 3.35). 04/2006; 2(1):39-42. DOI: 10.1098/rsbl.2005.0414
Source: PubMed

ABSTRACT Early environmental conditions have been suggested to influence subsequent locomotor performance in a range of species, but most measurements have been of initial (baseline) performance. By manipulating early growth trajectories in green swordtail fish, we show that males that underwent compensatory growth as juveniles had a similar baseline swimming endurance when mature adults to ad libitum fed controls. However, they had a reduced capacity to increase endurance with training, which is more likely to relate to Darwinian fitness. Compensatory growth may thus result in important locomotor costs later in life.

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