Introduction

This volume, Patterns of Growth and Development in the Genus Homo, presents an up-to-date review of the evolution of the pattern of human growth. Historically, there are many outstanding research developments in the study of this field, which may be called auxological paleontology. The Greek word auxein is used most often to denote a group of acidic organic substances that promote and regulate growth processes in plants. Human growth and development researchers appropriated this word and sometimes call themselves auxologists. In this chapter the phrase auxological paleontology is used to describe research into patterns of growth and development of fossil species. I briefly review a few milestones of research. Following this review, I describe my own research on the evolution of human life history.

Life-history theory is a field of biology concerned with the strategy an organism uses to allocate its energy toward growth, maintenance, reproduction, raising offspring to independence, and avoiding death. For a mammal, it is the strategy of when to be born, when to be weaned, how many and what type of pre-reproductive stages of development to pass through, when to reproduce, and when to die (Bogin, 1999; Smith & Tompkins, 1995).

Human life-history stages are presented in Table 2.1. Note that two of these stages, childhood and adolescence, are present only in living humans, and not in any other living primate species. The childhood stage is essentially the time between weaning (the cessation of breast-feeding) and the eruption of the first permanent molar tooth.