Human Paleobiology. By Robert B. Eckhardt. Cambridge University Press, Cambridge. ISBN 0 521 45160 4 (hardback).
Human palaeobiology uses fossil findings to reconstruct the lives of earlier humans, including feeding, mating, giving birth to offspring, avoiding predators, and coping with weather, parasites and disease. Examining population-specific behaviour and ways of life from bones is a challenging task, given that some earlier hominid species are today represented by incomplete remains of a few specimens, and moving from characteristics of these specimens to parameters of populations requires considerable knowledge about allometric changes in bones with age, influences of climate and nutrition on the development of body size and proportions, variations in population-specific patterns of sexual dimorphism, and so on. After all, individuals are only samples from the underlying populations in which the character states commonly must have been variable and polymorphic. For an average reader of this journal, familiar with analysing sample sizes of tens or hundreds of individuals, a step to the palaeontological world of this book may therefore be a large one.
Human biology focusing on old populations, whose only remains are fossil evidence, has traditionally been taxonomically orientated, probably partly due to the difficulties in turning piles of bones into entities approaching living organisms. In contrast to this, the palaeobiological approach towards fossil remains introduced in this book interprets the skeletal anatomy inferred from fossils in the broader contexts of physiology, biochemistry, genetics and behaviour of the individuals and populations represented by material remains. The aim of Robert Eckhardt is to provide a unifying framework for the study of past and present human populations in a range of changing environments by integrating evidence from studies of human adaptability, comparative primatology and molecular genetics.
The book covers a wide range of topics. The first, large part of it is dedicated to a historical overview on the development of both the fossil record and evolutionary theory over the past 150 years or so, starting from describing the first breakthrough fossil findings and their almost amusing early interpretations, and then examining the progress in the interpretation with time. The next chapters focus on the marks that can be left on the bones and teeth by short-term acclimatization to the changing environment, developmental plasticity or long-term genetical change. These are illustrated with several examples and the problems in the interpretation of such marks are discussed. The most exciting part of the book is when Eckhardt, by comparisons with baboons and chimpanzees, demonstrates that this same interpretative framework that helped to understand patters of variation in humans could also be extended to extant primate taxa. The last parts of the book address the questions of adaptive capacities and species richness in hominids over time, expansion patterns out of Africa and relevance of the species-concept in the scientific field where fossils of two individuals of the same species may differ in age by thousands of years, and where the error terms in the given ages of the fossils may range in hundreds of thousands of years.
Although fascinating reading for anyone interested in the study of past and present human populations, this is not a textbook for beginners. Without any earlier knowledge about the existing fossil evidence and the phylogeny of different hominids described so far, it is sometimes difficult to relate the examples presented in the book to any particular time era, stage of human evolution or species. This it not the least because often different species or individual fossil findings are only discussed using the name of their finding location or the common identification number allocated for each fossil finding (e.g. AL-288 for ‘Lucy’). For a non-expert, this is unfortunate and from time to time frustrating too – yet I believe that a book of this kind could have potential to interest a wide range of readers. In addition, the sometimes lack of clear structure and logical progression of information from chapter to chapter makes the book, at times, a confusing read. However, despite these criticisms, Human Paleobiology gives a good overview of the challenges, achievements and problems in understanding the way of life of human populations whose time was long since past.