Behavioural consequences of compensatory resource allocation during growth
Participants:
- Jan Lindstrom
- Neil Metcalfe
- Nick Royle
Funding: BBSRC - grant to Jan Lindstrom & Neil Metcalfe
Project Description:
A bad start during early growth may have long-lasting consequences on an individual's later behaviour and performance. This may be counteracted by compensatory mechanisms, such as "catch-up" growth - given a chance, an individual can accelerate growth and re-gain the normal growth trajectory. However, this compensation appears to carry costs: recent studies have revealed impaired physiological function and reduced lifespan later in life. In this study, we have four main aims:
1) We model the optimality of state-dependent catch-up growth strategies under various ecological and evolutionary scenarios
2) We quantify the extent to which fish (green swordtails, Xiphophorus helleri) subjected to poor growth conditions from early in life a) show variation in state-dependent resource allocation and b) show compensatory growth if growth conditions subsequently improve
3) We test to what extent compensation and relative investment in body- and tail-growth varies with ontogenetic stage
4) We test the long-term consequences of poor vs. good vs. compensated growth conditions as juveniles on a) burst and sustained swimming performance, b) survival rates, c) dominance status/competitive ability, d) attractiveness to potential mates (males), e) fecundity and offspring quality (females; time permitting inter-generational effects will also be studied.
References and Manuscripts in preparation:
Lindström, J., Metcalfe, N. B. & Royle, N. J.2005: How should animals with ornaments compensate for a bad start in life? A dynamic optimisation approach. Funct. Ecol., 19:421-428.
Royle, N. J., Lindström, J. & Metcalfe, N. B.2005: A poor start in life negatively affects dominance status in adulthood independent of body size in green swordtails Xiphophorus helleri. Proc.R. Soc. Lond. B, 272:1917-1922.
Royle, N. J., Lindström, J. & Metcalfe, N. B.2006: Effect of growth compensation on subsequent physical fitness in green swordtails Xiphophorus helleri. Biol. Lett. 2:39-42.
Royle, N. J., Metcalfe, N. B. & Lindström, J.2006: Sexual selection, growth compensation and fast-start swimming in green swordtails Xiphophorus helleri. Funct. Ecol., 20:662–669.
Walling, C. A., Royle, N. J., Metcalfe, N. B. & Lindström, J. 2007: Early nutritional conditions, growth trajectories and mate choice: does compensatory growth lead to a reduction in sexual attractiveness? Behav. Ecol. and Sociobiol., 61:1007-1014.
Royle, N. J., Metcalfe, N. B. & Lindström, J.: Compensatory growth increases longevity in a strongly sexually-selected species of fish. Manuscript
Royle, N. J., Lindström, J. & Metcalfe, N. B.: Social context-dependent mate choice: Females prefer rare males phenotypes in green swordtail Xiphophorus helleri. Manuscript
more to come later...
