Preface
The plan for this book goes back almost 20 years.
Already, at that time, it was possible to recognize
an extraordinary variation in metabolites and
processes superimposed upon the basic biochemical system of animals. Each species, each individual, in fact each type of cell of the multicellular organism possesses its own biochemical character, and this molecular variety, its biological significance, and its evolutionary development
throw up many interesting questions. The comparative approach that has been so productive at
the higher levels of complexity of morphology
and physiology can also be used to great effect at
the molecular level.
There are countless papers, reviews and other
articles on the subject of comparative biochemistry and evolution, but no actual textbook. This
is remarkable in so far as each area of science is
only really defined by its comprehensive representation in the literature. In the present book, I
have given my view of the starting points and the
content of comparative biochemistry. I would be
glad if further, related efforts by other authors
would follow this attempt at a definition of the
subject. In the widest sense, a comparative biochemistry should consider all organisms, but my
knowledge of the biochemistry of the bacteria,
algae, lower fungi and higher plants is unfortunately not sufficient for this purpose. In any case,
most of the available comparative biochemistry
data refer to animals.
This book is directed at zoologists as well as
biochemists. Biochemists may discover that molecular variation, though perhaps a complication
for general biochemical research, is in itself a fascinating scientific problem. Zoologists will find
that the molecular building blocks of animals display just as much colourful variation as do microscopic or macroscopic structures. They will see
that molecular variants can be understood partly
as adaptations to particular environmental conditions and partly as the result of diversification
along separate evolutionary lines. Finally, it will
be seen that biochemical characters can contribute greatly to understanding the origins of
organisms.
To provide the biochemist with a ready overview of the structural diversity of animals, the
book includes a simplified version of animal systematics; for further information on the classification, structure and life of particular animal species, the reader should consult the relevant textbooks. It is assumed that the zoologist reader has
a basic knowledge of biochemistry; important
general biochemical facts are in any case given for
many of the subjects covered.
I had already completed several chapters of
this book by the beginning of the 1970s. Because
of far-reaching changes in my employment conditions and duties as a high-school teacher, my
transfer from Berlin to Mainz, and the task of setting up a working group there, work on this book
was interrupted and could only be resumed in the
1980s. In the meantime, the data to be considered
had increased enormously; molecular biology, in
particular, had produced a gigantic body of relevant data. Today, a single person can no longer
keep track of all aspects of comparative biochemistry.
And so arises the well-known dilemma: the
portrayal of a large area of science by one or a
few authors inevitably leaves gaps and deficiencies; one book with contributions from many
authors generally leaves much to be desired in
uniformity and consistency. When I decided,
according to the original plan, to attempt as a
single author to bring together the whole of comparative biochemistry, the unavoidable deficiencies were very clear to me. I would be very grateful for any critical comments on gaps and mistakes in this presentation, but I would ask
biochemically oriented readers to judge the
whole work· and not only those sections most
familiar to them. I have researched the literature
up to the middle of 1988, but the reference lists
given for each chapter do not include the whole
of the consulted literature; this would require too
much space. Rather, I have referred to the latest
The plan for this book goes back almost 20 years.
Already, at that time, it was possible to recognize
an extraordinary variation in metabolites and
processes superimposed upon the basic biochemical system of animals. Each species, each individual, in fact each type of cell of the multicellular organism possesses its own biochemical character, and this molecular variety, its biological significance, and its evolutionary development
throw up many interesting questions. The comparative approach that has been so productive at
the higher levels of complexity of morphology
and physiology can also be used to great effect at
the molecular level.
There are countless papers, reviews and other
articles on the subject of comparative biochemistry and evolution, but no actual textbook. This
is remarkable in so far as each area of science is
only really defined by its comprehensive representation in the literature. In the present book, I
have given my view of the starting points and the
content of comparative biochemistry. I would be
glad if further, related efforts by other authors
would follow this attempt at a definition of the
subject. In the widest sense, a comparative biochemistry should consider all organisms, but my
knowledge of the biochemistry of the bacteria,
algae, lower fungi and higher plants is unfortunately not sufficient for this purpose. In any case,
most of the available comparative biochemistry
data refer to animals.
This book is directed at zoologists as well as
biochemists. Biochemists may discover that molecular variation, though perhaps a complication
for general biochemical research, is in itself a fascinating scientific problem. Zoologists will find
that the molecular building blocks of animals display just as much colourful variation as do microscopic or macroscopic structures. They will see
that molecular variants can be understood partly
as adaptations to particular environmental conditions and partly as the result of diversification
along separate evolutionary lines. Finally, it will
be seen that biochemical characters can contribute greatly to understanding the origins of
organisms.
To provide the biochemist with a ready overview of the structural diversity of animals, the
book includes a simplified version of animal systematics; for further information on the classification, structure and life of particular animal species, the reader should consult the relevant textbooks. It is assumed that the zoologist reader has
a basic knowledge of biochemistry; important
general biochemical facts are in any case given for
many of the subjects covered.
I had already completed several chapters of
this book by the beginning of the 1970s. Because
of far-reaching changes in my employment conditions and duties as a high-school teacher, my
transfer from Berlin to Mainz, and the task of setting up a working group there, work on this book
was interrupted and could only be resumed in the
1980s. In the meantime, the data to be considered
had increased enormously; molecular biology, in
particular, had produced a gigantic body of relevant data. Today, a single person can no longer
keep track of all aspects of comparative biochemistry.
And so arises the well-known dilemma: the
portrayal of a large area of science by one or a
few authors inevitably leaves gaps and deficiencies; one book with contributions from many
authors generally leaves much to be desired in
uniformity and consistency. When I decided,
according to the original plan, to attempt as a
single author to bring together the whole of comparative biochemistry, the unavoidable deficiencies were very clear to me. I would be very grateful for any critical comments on gaps and mistakes in this presentation, but I would ask
biochemically oriented readers to judge the
whole work· and not only those sections most
familiar to them. I have researched the literature
up to the middle of 1988, but the reference lists
given for each chapter do not include the whole
of the consulted literature; this would require too
much space. Rather, I have referred to the latest