The Character Concept in Evolutionary Biology. Edited by Günter P. Wagner. Academic Press, 2001. ISBN: 0 12 730055 4 (hardcover). 622 pp.
When teaching evolutionary biology to my undergraduates, I display an overhead page comprising a dozen different species concepts, each to them more arcane and confusing than the last. After their fear of having to memorize them all has been dispelled, comes the inevitable question of which is correct, best, or generally agreed upon. They are not happy to hear that there is no answer – what, after all, will they write on the exam? From the resultant wreckage of Mayr and colleagues I seek then to instill in them the idea that biological concepts, like other words, are tools with different uses for different problems, and usefulness for gaining novel insight as the main criterion for adoption.
This book is the ultimate in tool kits, and instruction guides, to a concept even more diverse, simple, yet profound than species: the concept of the character. Characters pervade all areas of evolutionary biology, from DNA to behaviour. They result from the human predilection to parse complex, integrated systems into a more or less tidy set of components, from behaviour, to linear measurements of morphology, to organ systems, tissues, cells, metabolism, proteins, RNA, DNA, and perhaps beyond to biochemicals, atoms and quarks. The tension between such extreme reductionism and a radical wholism that denies biological deconstruction, due to the obvious integration that defines organisms themselves, forms the core of this book. As for the species concepts above, there are no answers, only ideas, and this book is rich with them almost to a fault.
The Character Concept in Evolutionary Biology comprises 25 chapters divided into five main parts: history, new approaches to the character concept, operational character detection, the mechanistic nature of characters and evolutionary character origin. Within this framework, we find chapters that describe and define the character concept with methods including history and philosophy of science, biomathematics, developmental biology, functional morphology, molecular and quantitative genetics, optimality theory, systematics, palaeontology and phylogenetics. The level of scholarship is extraordinarily high, and all evolutionary biologists are likely to find at least several chapters to pique their interest. From Aristotle to butterfly eyespots, from genomics to limb buds, this book is inexorably integrative, and herein lies its main strength – by drawing from highly disparate disciplines, it should inspire us to consider with a fresh eye, and perhaps assemble and dissemble with new tools, the ‘characters’ that we each continually parse, analyse and discuss. But be warned – such inspiration will come at a cost: much of this book is heavy, dense reading, deeply imbued with specialist terminology, abstract argument and philosophy that to an empiricist and skeptic like myself sometimes borders on mysticism or psychology. For the brave professor, this book could serve as the basis for an ambitious graduate course in integrative evolutionary biology, though for most, it will provide insights mainly from the subset of chapters within or tangential to their own discipline, or in disciplines they are looking to explore.
Like my undergraduates learning about species concepts, I came away from this book a bit bewildered, with a flurry of incompatible concepts swimming in my brain, and as yet unsure what I had learned. But perhaps most importantly, I was aware of new questions and approaches that spring from close scrutiny of the character concept, and from stepping back to see how it applies at all levels of biological organization. Speaking of plant parts, Goethe once remarked ‘alles ist Blatt’ (all is leaf), as he, like the romantic poets, sought unity in all creation. This book helps us seek unity and integration though a concept: ‘alles ist Charakter’, the natural units of life.