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It is easy to be critical. Dr. Chiswick is to be congratulated on having pro-duced a text which is short and easy to read. It runs to 97 pages and is ex-tensively illustrated with photographs, x-rays and diagrams. The print is clearand bold with sub-headings, and there is selected reading at the end of eachchapter. It is certainly a bargain at this price.

J.D. Baum

Genetics, Environment and IntelligenceA. Oliverio (ed.)(xvii + 451 pages)North-Holland Publishing Company, Amsterdam, 1977642.55

Over a hundred years ago in a preamble to his Englishmen of Science,Francis Galton wrote:

“The effects of education and circumstances are so interwoven with those of naturalcharacter in determining a man’s position among his contemporaries, that I find itimpossible to treat them wholly apart. Still less is it possible completely to separateevidence relating to that portion of a man’s nature which is due to heredity from allthe rest.”

Since Galton expressed this view, our knowledge both of psychology andgenetics has grown enormously, yet the nature/nurture issue still servesto confuse and obscure. This is perhaps most evident in discussions on intel-ligence, which remain today as controversial as ever. The preoccupation withintellectual ability and IQ stems from the need to provide an adequate ex-planation for the fact that there are individual differences in intelligence. Inpsychology this is an old chestnut and, although it was clear to Galton thatboth nature and nurture were important sources of variation in intellectualperformance, the issue has been bedevilled by prejudice and often obscuredby fashion in scientific theorising.

The concept of general intelligence owes its present influential positionlargely to Alfred Binet, who developed tests for the French Ministry ofPublic Instruction to determine which children would be unable to profitfrom attendance in the elementary school. In essence Binet’s conception ofintelligence was concerned with a general ability to adapt successfully to theenvironment and its demands. As is quite often the case, the general concep-tion was lost amongst technical arguments and sophisticated measurements.The articles in this book underline the very broad interest and importanceof intelligence in the behavioural and the biological sciences.

The plan of the book is bold and the coverage extensive. In 21 essays andpapers grouped into five sections, attention is given to: the adaptive value, inan evolutionary sense, of intelligence; genetic aspects of learning andbehaviour in vertebrates and invertebrates; the effects of environmental vari-ation (including early experience, deprivation and nutrition) on the

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behaviour of animals; the genetics of intelligence in man; and the effects ofenvironmental variation on human mental performance. Inevitably suchwide-ranging considerations touch upon several issues which have beencentral to developmental studies and theorising for some years.

Caspari presents a succinct picture of contemporary behaviour geneticsand its evolutionary implications. His discussion of Ernst Mayr’s notion ofclosed (requiring little or no environmental potentiation) and open(modified by stimulation and experience) genetic programmes is particularlyhelpful, and provides a useful framework on which behavioural scientists canhang their ideas and data. Evolutionary implications and adaptations aretaken further by King, and questions of species comparisons are examinedby Warren, who concludes that the evolution of intelligence consists in thedevelopment of new and more sophisticated skills for learning and problem-solving at progressive phylogenetic levels.

The reviews by Bovet, on the effects of strain differences in learning in themouse, and by Wahlsten, on the genetics of brain structure, provide ampleevidence of the differences which can be produced by genetic variation.From these it is clear that the response of an organism to its environmentdepends greatly upon its heredity. The essentially interactive rather thanadditive nature of genetic and environmental variables is echoed inDenenberg’s chapter on early experience and subsequent behavioural devel-opment in animals. This interactional principle has an obvious consequence.The beguiling simplicity of the nature/nurture dichotomy must be aban-doned, since it cannot be sustained by anyone who is aware of only afraction of the relevant available data. The hope entertained by many thatbehavioural development is not really complicated must be given up; plainlyit is complicated and our existing theories of development will requirerevision and replacement. So too our data base must be further extended, asis evident from Smart’s excellent chapter on the effects of early malnutritionand later learning ability. The consequences of early malnutrition dependgreatly on many factors: the species, the timing of the nutritional insult,and the variables measured. Much more conceptual and empirical analysisremains to be done.

The final two sections of the book are devoted to studies with humans.Royce and Vandenburg each discuss work on the genetics of human intel-ligence, and Wilson reviews work on twins. Together these papers provide avaluable review of recent research on the genetics of human ability and intel-ligence. The emphasis which they give to developmental effects providesa refreshing change from the static view of intelligence which much recentcontroversy has centred upon. Papousek’s paper on individual differences inadaptive processes in infants offers a different starting point for the consi-deration of the growth of human intelligence. Papousek writes as a biologistand is concerned to understand individual variation in the behaviour of thenewborn, which he sees as crucial for a better understanding of basic learningprocesses. He has himself contributed importantly to neonatal studies, andthe difficulties which remain to be surmounted are all too familiar to him.

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To complete the volume there are five chapters devoted to a consideration ofenvironmental differences and human mental performance. Some of theseecho themes from the animal literature, the importance of early stimulation,the consequences of deprivation and the family environment. This workowes much to the concerns of many psychologists and educationalists whoare anxious to make their science serve humanitarian ends in relieving thelot of the deprived and underprivileged children within our society. Pro-grammes like ‘Headstart’ achieved much but they did not solve these deepproblems, and the material discussed in this section serves to underline someimportant maxims. The fist of these emerges from Marjoribank’s article onsocioeconomic status in relation to cognitive performance: it is that our ana-lyses must encompass not only the biological but also the sociological vari-ables. The essentially social nature of our species and the immense richnessof human culture along with the interaction of cultural and genetic evolutionare others.

This book deals with some of the central and enduring problems of thedevelopmental sciences. They are difficult problems, important not only asscientific issues leading us to seek new models of man and his development,but also because they have far-reaching social and political implications.Nature and nurture may be seen as opposites, but they comprise an indis-soluble unity. For the reader who has not worked in one or other of thefields treated by the contributors, the effort of linking all this material to-gether into a coherent framework will not be easy, and an integratingchapter would have helped greatly. However, though it will not be easyreading, the book should be valuable to ‘students’ at many levels. The price,even in these inflationary days, is shocking and one almost wonders if there isa plot to prevent the book being read.

Kevin Connolly