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Morphology of flowers and inflorescences
TREE vol. 5, no. 10, October
humans and honey badgers working in collaboration with birds, the honeyguides) and will house an assemblage of smaller associates, in which bacteria, yeasts, mites, beetles and flies interact in ways that may or may not ultimately benefit the bees. As well as stingless bees, other social and solitary bees are considered in comparable detail. Roubik bringstogetherthefragmentarywork on the biology of the exotic and ornamental euglossine orchid bees of the neotropics, pointing out that we still do not know why male orchid bees collect orchid fragrances and other compounds, including DDT. In the context of the wider treatment of tropical bee ecology, he provides an authoritative synthesis of the ecology of Africanized honeybees in the neotropical regions, where their spread is causing so much interest and concern.
1990
One way to begin to understand the ecology of a complex community is to focus on a single group. Bees are particularly appropriate, because of their interactions with plantsand with so many other organisms. In this sense, the book offers a picture of an important part of the tropical world. But inevitably the picture is still patchy. Like palaeontologists faced with an incomplete fossil record, tropical ecologists must try to complete the picture by setting fragments of evidence in a matrix of speculation. The fragments are sometimes very small and far apart, because (with notable exceptions, such as Roubik’s own work) so many tropical studies are short-term and opportunistic, lacking the continuity and context of known natural history that is our unacknowledged endowment in Europe. If we start to build the picture too soon, the speculative matrix will
be extensive, and may solidify into gospel before it can be tested. Roubik acknowledges that risk but argues persuasively that over-long delay would be even more dangerous. Many of the perennial eusocial species that dominate tropical bee communities are denizens of undisturbed rain forest, nesting in mature, living trees. As forests are destroyed, bee communities will be lost. As a stimulus for further research, this book is needed now. It will be valued for its substantial and wideranging bibliography, as well as for the text, which is a carefully organized mosaic of sparkling fragments giving tempting glimpses of a relatively unexplored world.
into the early 198Os, literature of the last 20 years has not been used in the text to any great extent. There are fields of botanical research that have had a large impact on our understanding of floral structure in the’last 20 years. Since the 1970s a new wave of ontogenetic studies, made possible by the availabilityofthescanningelectron microscope, led to an expansion of our knowledge of patterns and plasticity of floral ontogeny2. In the 198Os, unprecedented paleobotanical finds of Cretaceous flowers modified our view on early floral evolution*5. Extensive studies (e.g. Ref. 6) of reproductive biology brought to light an immense amount of plasticity in floral behaviour. Systematic studies have influenced our knowledge of evolutionary trends in flowers. These developments have not been sufficiently incorporated into this book. The three main sections of the book are: ‘Morphology of flowers’, ‘Morphology of the inflorescence’ and ‘The flower as a formal and functional entity - aspects of the biology of pollination and dispersal’. Emphasis is laid on basic morphological categories, such as ‘leaf’ and ‘axis’ in the flower, and on subcategories like sepals, petals, stamens and carpels. In contrast, although fusions of floral organs are well treated, synorganization is not extensively discussed. Many floral parts, which appear as mere curiosities if discussed in isolation, make more sense in the light of floral synorganization. The emphasis throughout is on temperate plant groups.
All the sections contain a large number of perhaps unfamiliar technical terms. These may have proved useful to many morphologists, but they may also hide a dangerous side: if we try to understand the evolution of a particular group of plants we have to approach it in a manner as flexible as possible rather than be diverted by a too strict and closemeshed terminology. Many of the phenomena discussed in the work are excellently illustrated with elaborate line drawings and (especially for the inflorescences) beautiful photographs. The book, in its rich content, is certainly a treasure for every botanist who is interested in floral structure. But it also shows how much we now need more modern syntheses on flower structure, function and evolution.
Sarah A. Corbet University, Downing Deptof Zoology,Cambridge Street,Cambridge CB23EJ,UK
Floral Structure Morphology of Flowers and lnflorescences by F. Weberling, Cambridge University Press, 1989. f55.00/$110.00 hbk (xx + 405 pages) ISBN 0 52125134 6 How can we understand flowers? One of the most profitable apmorproaches is comparative phology. It is important to update morphological surveys of all groups of organisms for the further advancement of evolutionary biology, especially since - as Riedl’ puts it: ‘there have been, say 200 years of scientific biology, and for 150 of those years morphology was its backbone. But after scarcely 50 years of experimental study we are on the point of losing this backbone entirely. This would mean losing the method which gave scientific proof of relationship, descent, and phylogeny in general’. In this light, the translation of Weberling’s work is of great significance and must be warmly welcomed. The first publication of Morphology of Flowers and Infiorescences, in 1981, was in German. Except for the addition of a glossary and some new references there are no changes in this edition. The translation by R.J. Pankhurst is very careful and keeps the personal style of the author. The book is based on what has been studied by German and other European morphologists up to the early 1970s. Therefore, the statement on the cover that the book gives a ‘summary of current understanding of flower and inflorescence morphology’ is misleading. Although there is a reference list that extends 348
Peter K. Endress Instituteof Systematic Botany,Universityof Zurich, Zollikerstrasse 107,EOOEZurich, Switzerland References 1 Riedl, R. (1978) Order in Living Organisms, Wiley 2 Endress, P.K. (1990) Biol. J. Linn. Sot. 39,153-175 3 Dilcher, D.L. (1979) Rev. Palaeobot. Palynol. 27, 291-328 4 Friis. E.M.. Chaloner. W.G. and Crane, P.R., eds (1987) The Origins of Angiosperms and Their Biological Consequences, Cambridge University Press 5 Crane, P.R. and Blackmore, S., eds (1989) Evolution, Systematics, and Fossil History of the Hammelidae (Vol. I), Clarendon Press 6 Richards, A.J. (1986) P/ant Breeding Systems, Allen & Unwin
humans and honey badgers working in collaboration with birds, the honeyguides) and will house an assemblage of smaller associates, in which bacteria, yeasts, mites, beetles and flies interact in ways that may or may not ultimately benefit the bees. As well as stingless bees, other social and solitary bees are considered in comparable detail. Roubik bringstogetherthefragmentarywork on the biology of the exotic and ornamental euglossine orchid bees of the neotropics, pointing out that we still do not know why male orchid bees collect orchid fragrances and other compounds, including DDT. In the context of the wider treatment of tropical bee ecology, he provides an authoritative synthesis of the ecology of Africanized honeybees in the neotropical regions, where their spread is causing so much interest and concern.
1990
One way to begin to understand the ecology of a complex community is to focus on a single group. Bees are particularly appropriate, because of their interactions with plantsand with so many other organisms. In this sense, the book offers a picture of an important part of the tropical world. But inevitably the picture is still patchy. Like palaeontologists faced with an incomplete fossil record, tropical ecologists must try to complete the picture by setting fragments of evidence in a matrix of speculation. The fragments are sometimes very small and far apart, because (with notable exceptions, such as Roubik’s own work) so many tropical studies are short-term and opportunistic, lacking the continuity and context of known natural history that is our unacknowledged endowment in Europe. If we start to build the picture too soon, the speculative matrix will
be extensive, and may solidify into gospel before it can be tested. Roubik acknowledges that risk but argues persuasively that over-long delay would be even more dangerous. Many of the perennial eusocial species that dominate tropical bee communities are denizens of undisturbed rain forest, nesting in mature, living trees. As forests are destroyed, bee communities will be lost. As a stimulus for further research, this book is needed now. It will be valued for its substantial and wideranging bibliography, as well as for the text, which is a carefully organized mosaic of sparkling fragments giving tempting glimpses of a relatively unexplored world.
into the early 198Os, literature of the last 20 years has not been used in the text to any great extent. There are fields of botanical research that have had a large impact on our understanding of floral structure in the’last 20 years. Since the 1970s a new wave of ontogenetic studies, made possible by the availabilityofthescanningelectron microscope, led to an expansion of our knowledge of patterns and plasticity of floral ontogeny2. In the 198Os, unprecedented paleobotanical finds of Cretaceous flowers modified our view on early floral evolution*5. Extensive studies (e.g. Ref. 6) of reproductive biology brought to light an immense amount of plasticity in floral behaviour. Systematic studies have influenced our knowledge of evolutionary trends in flowers. These developments have not been sufficiently incorporated into this book. The three main sections of the book are: ‘Morphology of flowers’, ‘Morphology of the inflorescence’ and ‘The flower as a formal and functional entity - aspects of the biology of pollination and dispersal’. Emphasis is laid on basic morphological categories, such as ‘leaf’ and ‘axis’ in the flower, and on subcategories like sepals, petals, stamens and carpels. In contrast, although fusions of floral organs are well treated, synorganization is not extensively discussed. Many floral parts, which appear as mere curiosities if discussed in isolation, make more sense in the light of floral synorganization. The emphasis throughout is on temperate plant groups.
All the sections contain a large number of perhaps unfamiliar technical terms. These may have proved useful to many morphologists, but they may also hide a dangerous side: if we try to understand the evolution of a particular group of plants we have to approach it in a manner as flexible as possible rather than be diverted by a too strict and closemeshed terminology. Many of the phenomena discussed in the work are excellently illustrated with elaborate line drawings and (especially for the inflorescences) beautiful photographs. The book, in its rich content, is certainly a treasure for every botanist who is interested in floral structure. But it also shows how much we now need more modern syntheses on flower structure, function and evolution.
Sarah A. Corbet University, Downing Deptof Zoology,Cambridge Street,Cambridge CB23EJ,UK
Floral Structure Morphology of Flowers and lnflorescences by F. Weberling, Cambridge University Press, 1989. f55.00/$110.00 hbk (xx + 405 pages) ISBN 0 52125134 6 How can we understand flowers? One of the most profitable apmorproaches is comparative phology. It is important to update morphological surveys of all groups of organisms for the further advancement of evolutionary biology, especially since - as Riedl’ puts it: ‘there have been, say 200 years of scientific biology, and for 150 of those years morphology was its backbone. But after scarcely 50 years of experimental study we are on the point of losing this backbone entirely. This would mean losing the method which gave scientific proof of relationship, descent, and phylogeny in general’. In this light, the translation of Weberling’s work is of great significance and must be warmly welcomed. The first publication of Morphology of Flowers and Infiorescences, in 1981, was in German. Except for the addition of a glossary and some new references there are no changes in this edition. The translation by R.J. Pankhurst is very careful and keeps the personal style of the author. The book is based on what has been studied by German and other European morphologists up to the early 1970s. Therefore, the statement on the cover that the book gives a ‘summary of current understanding of flower and inflorescence morphology’ is misleading. Although there is a reference list that extends 348
Peter K. Endress Instituteof Systematic Botany,Universityof Zurich, Zollikerstrasse 107,EOOEZurich, Switzerland References 1 Riedl, R. (1978) Order in Living Organisms, Wiley 2 Endress, P.K. (1990) Biol. J. Linn. Sot. 39,153-175 3 Dilcher, D.L. (1979) Rev. Palaeobot. Palynol. 27, 291-328 4 Friis. E.M.. Chaloner. W.G. and Crane, P.R., eds (1987) The Origins of Angiosperms and Their Biological Consequences, Cambridge University Press 5 Crane, P.R. and Blackmore, S., eds (1989) Evolution, Systematics, and Fossil History of the Hammelidae (Vol. I), Clarendon Press 6 Richards, A.J. (1986) P/ant Breeding Systems, Allen & Unwin