- Email: [email protected]
The development of brain and behaviour in the chicken
1140
Animal
Behaviour,
50, 4
ment. In fact no other avian species has been studied in such detail, partly because of the easein
standing development and does an excellent job of linking the chick findings to related work on other species,particularly in birds and to some extent in mammals as well. The book should be of great interest to neuroscientists and ethologists, as well as to a more general biology audience, being aimed at higher level undergraduates and researchersalike. There are seven chapters; each begins with a short and snappy summary of the key points and concludes with a discussion of how the main findings may be interpreted and the author’s view of what the future might hold. Each chapter contains several photographs and simple, but accurate, figures of somecof the key findings. Chapter 1 examines how brain and behaviour develop in the embryo, prior to, and including, the process of hatching, while chapter 2 deals with how the environment influences embryonic development. Chapters 3,4 and 5 focus on the changes that occur soon after hatching. Chapter 3 considers the importance of learning, and includes sections on filial and sexual imprinting, the development of fear behaviour, learning to feed, and how social hierarchies and sleep patterns are formed. Chapter 4 switches gear to consider the underlying neural changes in the brain, and discussesasymmetrical development of the forebrain, one of the areas of research in which Rogers has been especially prominent. In chapter 5, the approach is a more behavioural one, considering how behavioural changes occur in the early days out of the egg. In some ways the last two chapters are the most interesting of all because they are really quite novel. In chapter 6 Rogers does an excellent job of comparing the chick work with similar findings in other species and there is a section on how relevant avian studies of lateralization are for studies in mammals. The greatest surprise of all is chapter
obtaining
7 which
squirrels. In addition, however, Hoogland’s comparative approach, and the breadth of topics he covers, will make the book an interesting and valuable reference for mammalogists and behavioural ecologists alike. SCOTT
NUNES
Department of Zoology, Michigan State University, East Lansing, MI 48824, U.S. A. References Gowaty, P. A. & Lennarts, M. R. 1985. Sex ratios of nestling and fledgling red-cockaded woodpeckers (Picoides borealis) favor males. Am. Nat., 126, 341353. Holekamp, K. E. & Smale, L. 1995. Rapid change in offspring sex ratio after clan fission in the spotted hyena. Am. Nat., 145, 261-278. Hrdy, S. B. 1974. Male-male competition and infanticide among the langurs (Presbytis entellus) of Abu, Rajasthan. Folia primatol., 22, 19-58. Hrdy, S. B. 1979. Infanticide among animals: a review, classification, and examination of the implications for the reproductive strategies of females. Ethol. Sociobiol., 1, 13-40. King, J. A. 1955. Social behavior, social organization, and population dynamics of a black-tailed prairiedog town in the Black Hills of South Dakota. Contrib. Lab.
vertebr.
Biol.
Univ.
Mich.,
67, 1-123.
The Development of Brain and Behaviour in the Chicken. By LESLEY J. ROGERS. Wallingford: CAB International (1995). Pp. ix+273. Price 545. The humble chicken has proved to be an excellent model for understanding mechanisms of developand rearing
young
chicks, and partly
because they are relatively straightforward to study in captivity at a number of levels. In fact, one of the beauties of the chick as a model is that it is particularly amenable to an interdisciplinary approach, and changes in behaviour and brain are seen as the product of a complex series of interactions between genes, hormones, present environment and past experience. The impact of the chick work has been great, and not just in birds: an understanding of how the brain and behaviour of chickens develop has been instrumental in studies of animal development as a whole. The book is extremely well written, and what is more, it is not just a book about the bird brain. Throughout the text the author emphasizes the importance of an integrative approach to under-
addresses
the animal
welfare
question
with the intriguing title of ‘Can a brain be domesticated? It may seem strange at first that a book on development should end with issues about animal welfare, especially when so much of the book has described work involving invasive surgery, and yet Rogers does have a point: thanks to factory farming, the chicken has been over exploited and under respected and it is up to us scientists to help put the matter right (Dawkins 1980). Intrigued? Buy the book: it’s a must! NICKY
Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, U.K.
CLAYTON
Software and Book Reviews
References
1141
own species. Combine the two and you have an irresistible mixture, guaranteed to generate interest and strong feelings. For someone not wishing their researchto go unnoticed, and with a flair for telling a good story, this is a field with enormous potential. The lure of this topic and the reputation of the Human Sperm Competition: Copulation, Masturauthors was nowhere better demonstrated than at bation and Injidelity. By R. R. BAKER & M. A. the International Society for Behavioral Ecology BELLS. London: Chapman & Hall (1994). (ISBE) meeting in Princeton in 1992 where Baker & Pp. xvi+353. Price g45.00. Bellis gave successivetalks in the same sessionto a Booksare a bit like children. They can get started packed auditorium, while speakers in the parallel either by accident or after careful planning. Ges- sessionstalked virtually to themselves. tation can be either sickening or invigorating, and Scientists make their mark in different ways. the birth itself can be straightforward or excruci- One measure of successin science is how much ating. Once out in the world authors and parents attention people pay to your research. There is no both hope their ‘offspring’ will do well, and are doubt that Baker hasmade his mark mainly by acutely sensitive to criticism and desperate for encouraging others to think about things in new praise.This particular literary progeny gets both. ways. And this is certainly an approach that I Ever since Leeuwenhoek observed his own sper- found inspirational when he taught me as an matozoa in 1677, the mechanics of human repro- undergraduate. In this book Baker & Bellis have duction has continued to stimulate research, not synthesized their extensive ideas about human leastbecausethere is often a good living to be made reproduction. The essenceis that human females from understanding human infertility. Baker & routinely copulate outside the pair bond and do so Bellis’rationale, however, could not be more differ- at the time when conception is most likely. ent from those whose motivation is mainly in vitro Moreover, by regulating the proportion of sperm fertilization. Their approach is an evolutionary one, they reject or retain, often mediated through first stimulated by Parker’s (1970) study of insect orgasm, females exert considerable control over sperm competition. Subsequently, and somewhat which male fertilizes their eggs. Males ‘fight back belatedly, the study of sperm competition in other by adjusting ejaculate size and quality, the latter taxa flourished, and is now a major area of re- mediated through masturbation. Finally, varisearch. It was therefore inevitable that someone ation in sperm morphology is adaptive (the would eventually look at humans in this way. Smith kamikaze sperm hypothesis) and different types (1984) was among the first, in the final chapter of serve different roles in sperm competition. hisseminal book on sperm competition and animal The authors present a huge amount of informating systems. Baker & Bellis picked up where mation in support of their ideas. However, I was Smith left off and in the intervening years have disappointed by their book. I was disappointed by produced an enormous range of original and stimu- its design and layout and its numerous unaesthetic lating ideas. Scienceoften leaps forward by looking images (illustrations and vignettes can enhance a at old problems with fresh eyes, as exemplified by book, but these do not and the publishers have the successof using evolutionarily tinted contact done their authors, themselves and their readers a lenses to view animal behaviour: the successof disserviceby not having used a decent artist). But behavioural ecology is obvious. The potential for worse than that, despite the authors’ strong claims understanding human sexual behaviour was for their data, I was left feeling unconvinced. I would have preferred rather lessinformation more therefore considerable. Starting with his studies of insect migration carefully analysed and presented in a more (Baker 1978) and later with human navigation thoughtful manner. One example will suffice. Short Baker has undoubtedly enjoyed the response that (1977) noticed that among the four great apes, his novel and thought-provoking ideas have elic- chimpanzees had the largest testes relative to their ited. In the preface to his book on the magnetic body mass, and gorillas the smallest. He suggested sensein humans he wrote: ‘I have no doubt that the that this difference may be due to a difference in the initial response to . this book will be one of species’ mating system, and the likelihood of feopposition and disbelief (Baker 1981). He was males being inseminated by multiple males (Short right (see references cited in Baker 1987) and his 1977). Harvey & Harcourt (1984) later used data recent ventures into human reproduction continue from a wide range of primates and confirmed the to feed the controversy he so obviously relishes. positive relationship between relative testis sizeand Most of us have a deep-seated fascination with the intensity of sperm competition. Studies on taxa reproduction, and are passionately interested in our as diverse as butterflies, frogs and birds have Dawkins,M. S. 1980.Animal Suffering: The Science Animal Welfare. London: Chapman & Hall.
of
Animal
Behaviour,
50, 4
ment. In fact no other avian species has been studied in such detail, partly because of the easein
standing development and does an excellent job of linking the chick findings to related work on other species,particularly in birds and to some extent in mammals as well. The book should be of great interest to neuroscientists and ethologists, as well as to a more general biology audience, being aimed at higher level undergraduates and researchersalike. There are seven chapters; each begins with a short and snappy summary of the key points and concludes with a discussion of how the main findings may be interpreted and the author’s view of what the future might hold. Each chapter contains several photographs and simple, but accurate, figures of somecof the key findings. Chapter 1 examines how brain and behaviour develop in the embryo, prior to, and including, the process of hatching, while chapter 2 deals with how the environment influences embryonic development. Chapters 3,4 and 5 focus on the changes that occur soon after hatching. Chapter 3 considers the importance of learning, and includes sections on filial and sexual imprinting, the development of fear behaviour, learning to feed, and how social hierarchies and sleep patterns are formed. Chapter 4 switches gear to consider the underlying neural changes in the brain, and discussesasymmetrical development of the forebrain, one of the areas of research in which Rogers has been especially prominent. In chapter 5, the approach is a more behavioural one, considering how behavioural changes occur in the early days out of the egg. In some ways the last two chapters are the most interesting of all because they are really quite novel. In chapter 6 Rogers does an excellent job of comparing the chick work with similar findings in other species and there is a section on how relevant avian studies of lateralization are for studies in mammals. The greatest surprise of all is chapter
obtaining
7 which
squirrels. In addition, however, Hoogland’s comparative approach, and the breadth of topics he covers, will make the book an interesting and valuable reference for mammalogists and behavioural ecologists alike. SCOTT
NUNES
Department of Zoology, Michigan State University, East Lansing, MI 48824, U.S. A. References Gowaty, P. A. & Lennarts, M. R. 1985. Sex ratios of nestling and fledgling red-cockaded woodpeckers (Picoides borealis) favor males. Am. Nat., 126, 341353. Holekamp, K. E. & Smale, L. 1995. Rapid change in offspring sex ratio after clan fission in the spotted hyena. Am. Nat., 145, 261-278. Hrdy, S. B. 1974. Male-male competition and infanticide among the langurs (Presbytis entellus) of Abu, Rajasthan. Folia primatol., 22, 19-58. Hrdy, S. B. 1979. Infanticide among animals: a review, classification, and examination of the implications for the reproductive strategies of females. Ethol. Sociobiol., 1, 13-40. King, J. A. 1955. Social behavior, social organization, and population dynamics of a black-tailed prairiedog town in the Black Hills of South Dakota. Contrib. Lab.
vertebr.
Biol.
Univ.
Mich.,
67, 1-123.
The Development of Brain and Behaviour in the Chicken. By LESLEY J. ROGERS. Wallingford: CAB International (1995). Pp. ix+273. Price 545. The humble chicken has proved to be an excellent model for understanding mechanisms of developand rearing
young
chicks, and partly
because they are relatively straightforward to study in captivity at a number of levels. In fact, one of the beauties of the chick as a model is that it is particularly amenable to an interdisciplinary approach, and changes in behaviour and brain are seen as the product of a complex series of interactions between genes, hormones, present environment and past experience. The impact of the chick work has been great, and not just in birds: an understanding of how the brain and behaviour of chickens develop has been instrumental in studies of animal development as a whole. The book is extremely well written, and what is more, it is not just a book about the bird brain. Throughout the text the author emphasizes the importance of an integrative approach to under-
addresses
the animal
welfare
question
with the intriguing title of ‘Can a brain be domesticated? It may seem strange at first that a book on development should end with issues about animal welfare, especially when so much of the book has described work involving invasive surgery, and yet Rogers does have a point: thanks to factory farming, the chicken has been over exploited and under respected and it is up to us scientists to help put the matter right (Dawkins 1980). Intrigued? Buy the book: it’s a must! NICKY
Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, U.K.
CLAYTON
Software and Book Reviews
References
1141
own species. Combine the two and you have an irresistible mixture, guaranteed to generate interest and strong feelings. For someone not wishing their researchto go unnoticed, and with a flair for telling a good story, this is a field with enormous potential. The lure of this topic and the reputation of the Human Sperm Competition: Copulation, Masturauthors was nowhere better demonstrated than at bation and Injidelity. By R. R. BAKER & M. A. the International Society for Behavioral Ecology BELLS. London: Chapman & Hall (1994). (ISBE) meeting in Princeton in 1992 where Baker & Pp. xvi+353. Price g45.00. Bellis gave successivetalks in the same sessionto a Booksare a bit like children. They can get started packed auditorium, while speakers in the parallel either by accident or after careful planning. Ges- sessionstalked virtually to themselves. tation can be either sickening or invigorating, and Scientists make their mark in different ways. the birth itself can be straightforward or excruci- One measure of successin science is how much ating. Once out in the world authors and parents attention people pay to your research. There is no both hope their ‘offspring’ will do well, and are doubt that Baker hasmade his mark mainly by acutely sensitive to criticism and desperate for encouraging others to think about things in new praise.This particular literary progeny gets both. ways. And this is certainly an approach that I Ever since Leeuwenhoek observed his own sper- found inspirational when he taught me as an matozoa in 1677, the mechanics of human repro- undergraduate. In this book Baker & Bellis have duction has continued to stimulate research, not synthesized their extensive ideas about human leastbecausethere is often a good living to be made reproduction. The essenceis that human females from understanding human infertility. Baker & routinely copulate outside the pair bond and do so Bellis’rationale, however, could not be more differ- at the time when conception is most likely. ent from those whose motivation is mainly in vitro Moreover, by regulating the proportion of sperm fertilization. Their approach is an evolutionary one, they reject or retain, often mediated through first stimulated by Parker’s (1970) study of insect orgasm, females exert considerable control over sperm competition. Subsequently, and somewhat which male fertilizes their eggs. Males ‘fight back belatedly, the study of sperm competition in other by adjusting ejaculate size and quality, the latter taxa flourished, and is now a major area of re- mediated through masturbation. Finally, varisearch. It was therefore inevitable that someone ation in sperm morphology is adaptive (the would eventually look at humans in this way. Smith kamikaze sperm hypothesis) and different types (1984) was among the first, in the final chapter of serve different roles in sperm competition. hisseminal book on sperm competition and animal The authors present a huge amount of informating systems. Baker & Bellis picked up where mation in support of their ideas. However, I was Smith left off and in the intervening years have disappointed by their book. I was disappointed by produced an enormous range of original and stimu- its design and layout and its numerous unaesthetic lating ideas. Scienceoften leaps forward by looking images (illustrations and vignettes can enhance a at old problems with fresh eyes, as exemplified by book, but these do not and the publishers have the successof using evolutionarily tinted contact done their authors, themselves and their readers a lenses to view animal behaviour: the successof disserviceby not having used a decent artist). But behavioural ecology is obvious. The potential for worse than that, despite the authors’ strong claims understanding human sexual behaviour was for their data, I was left feeling unconvinced. I would have preferred rather lessinformation more therefore considerable. Starting with his studies of insect migration carefully analysed and presented in a more (Baker 1978) and later with human navigation thoughtful manner. One example will suffice. Short Baker has undoubtedly enjoyed the response that (1977) noticed that among the four great apes, his novel and thought-provoking ideas have elic- chimpanzees had the largest testes relative to their ited. In the preface to his book on the magnetic body mass, and gorillas the smallest. He suggested sensein humans he wrote: ‘I have no doubt that the that this difference may be due to a difference in the initial response to . this book will be one of species’ mating system, and the likelihood of feopposition and disbelief (Baker 1981). He was males being inseminated by multiple males (Short right (see references cited in Baker 1987) and his 1977). Harvey & Harcourt (1984) later used data recent ventures into human reproduction continue from a wide range of primates and confirmed the to feed the controversy he so obviously relishes. positive relationship between relative testis sizeand Most of us have a deep-seated fascination with the intensity of sperm competition. Studies on taxa reproduction, and are passionately interested in our as diverse as butterflies, frogs and birds have Dawkins,M. S. 1980.Animal Suffering: The Science Animal Welfare. London: Chapman & Hall.
of