Introduction

If there are indeed many pathways to the adult endpoint during growth, what becomes of interest is the nature of those different pathways and, more significantly, the consequences of differences in pathways for early survival, for the timing of the onset of reproductive activity, and for subsequent lifespan. This chapter explores some of the strategies for growth observed in primates, and outlines potential consequences of these strategies. I do this in the context of an abundance of detailed literature on growth rates, growth constraints and models of rates of growth for humans (see for example Bogin, 1999) and non-human primates (e.g. Leigh, 1996). Models of growth can provide explanations for primate life history variation (Leigh, 1995; Dirks & Bowman, 2007) and, in addition, potentially elucidate the variation that exists at the level of the individual and population between rapid and late maturation (e.g. Wilson et al., 1983; Bercovitch & Berard, 1993; Setchell et al., 2001; Altmann & Alberts, 2005).

Physical maturation is obviously a consequence of growth, but the timing of physiological or hormonal reproductive onset, rather than simply attained size, determines much of the subsequent reproductive success of the individual. Early reproduction, combined with high survival, provides significant advantages in terms of lifetime reproductive success.