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Written for a wide audience of biologists and philosophers, this text gives an excellent overview of the species problem without delving into the many feuds between the different schools of taxonomy. A perfect companion for field taxonomists and students dealing with the problem.

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A readily comprehensible guide for biologists, field taxonomists and interested laymen to one of the oldest problems in biology: the species problem. Written by a geneticist with extensive experience in field taxonomy, this practical book provides the sound scientific background to the problems arising with classifying organisms according to species. It covers the main current theories of specification and gives a number of examples that cannot be explained by any single theory alone.

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Foreword
Preface
Introduction
Are species constructs of the human mind?
Why is there a species problem?
What are traits in taxonomy?
Diversity within the species: polymorphisms and the polytypic species
Biological species as a gene-flow community
The cohesion of organisms through genealogical lineage (cladistics)
Outlook
Glossary

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"The question whether species really exist and if so, what the nature of their existence is, remains a central problem in the philosophy of biology, even after many decades of thinking and debating. Kunz´s book clearly shows that the debate is far from over". ( Acta Biotheor , 1 June 2013)

"This year´s version is an interesting hybrid that lays out the various concepts, but deals with them with the practicing biologist in mind, not the philosopher. For that, I applaud it." ( Teaching Biology , 20 December 2012)

"Recommended for those with a technical or semi-technical interest in systematics." (Ian Paulsen, Birdbooker Report 244, Oct 2012)

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Currently a professor in Düsseldorf, Germany, Werner Kunz studied biology, chemistry, and physics in Münster and spent two postdoc years at Yale University in New Haven, U.S.A. Although he was educated as a zoologist, he switched to Drosophila genetics and worked on chromosomes and ribosomal DNA. He later changed his field of interest again, carrying out research into molecular parasitology, and for the past ten years has been participating in the teaching of philosophy of science. Professor Kunz continues the hobby he began at a very early age, photographing birds and butterflies as a field biologist all over the globe.

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