Early body condition, time budgets and the acquisition of foraging skills in meerkats ALEX THORNTON Department of Zoology, University of Cambridge (Received 2 February 2007; initial acceptance 13 April 2007; final acceptance 3 August 2007; published online ---; MS. number: 9259R) Early body condition commonly has important downstream effects on fitness. One, as yet unexplored, mechanism behind these effects may be that condition in early life affects time budgets and hence oppor- tunities to learn critical skills. Meerkat, Suricata suricatta, pups must choose between begging for food from helpers and foraging for themselves. I found that pups in good condition early in life invested more time in foraging than individuals in poor condition and subsequently developed greater foraging efficiency, which was maintained in later life. Young pups spent an average of 18% of their time foraging, even though all pups were initially incompetent foragers and gained few direct benefits from their attempts. Pups whose hunger was reduced through experimental provisioning increased their investment in forag- ing. This suggests that investment in foraging is mediated by available energy reserves and raises the pos- sibility that, although foraging is energetically costly, pups may gain long-term benefits by practising. Surprisingly, manipulating body weight through long-term experimental provisioning did not result in in- creased investment in foraging or improved foraging efficiency. Possible explanations for this result are considered. The findings presented here provide some support for the hypothesis that high body condition allows individuals to invest time in costly foraging practice, leading to the development of skills. These effects, acting in tandem with other processes such as differential neural development, may help to explain common links between early condition and future fitness. Ó 2007 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved. Keywords: downstream effects; early condition; foraging skills; learning; meerkat; Suricata suricatta Body condition in early life has important downstream effects on factors including metabolic rate (Verhulst et al. 2006), disease resistance (Lummaa 2003; Worthman & Ku- zara 2005), growth (Johnsson & Bohlin 2006), sexual at- tractiveness (Gustafsson et al. 1995; Nowicki et al. 1998) and survival and reproductive success (Lindstro ¨m 1999). These effects may be mediated through a variety of mech- anisms including reduced investment in tissue develop- ment by individuals of low birth weight (Metcalfe & Monaghan 2001), physiological costs of compensatory growth (Metcalfe & Monaghan 2001; Johnsson & Bohlin 2006) and increased competitive abilities of larger individ- uals (Kruuk et al. 1999). In some cases, the downstream effects of early body condition may be mediated through learning of information or skills of critical fitness value. For example, Nowicki et al. (1998) suggested that song learning in pas- serines may be influenced by the effects of nutritional stress in early life on neural development. However, the de- velopment of critical skills may not always be determined directly by energetic constraints on neural development during the period of growth. It is increasingly clear that adult phenotypes can also be affected by what individuals do during the juvenile period. For example, fish that eat hard items as juveniles develop larger jaw muscles than peers that feed only on soft items (Mittelbach et al. 1999). In some situations, juveniles may engage in behav- iour which, while it has no obvious current benefit, may serve to accelerate physical or behavioural development which will be beneficial in the future. Infant spotted hy- enas, Crocuta crocuta, for example, spend a great deal of time chewing on bones and other objects. Although it pro- vides no nutritional rewards, this jaw exercise promotes the development of jaw muscles and skull bones which will later be necessary for the consumption of antelope car- casses (Holekamp & Smale 1998; West-Eberhard 2003). Correspondence: A. Thornton, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, U.K. (email: jant2@cam.ac.uk). ARTICLE IN PRESS 1 0003e 3472/07/$30.00/0 Ó 2007 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved. ANIMAL BEHAVIOUR, 2007, --, --e-- doi:10.1016/j.anbehav.2007.08.004 Please cite this article in press as: Alex Thornton, Early body condition, time budgets and the acquisition of foraging skills in meerkats, Anim. Behav. (2007), doi:10.1016/j.anbehav.2007.08.004