Table Of ContentThe Evolutionary Origins of Life and Death
The Evolutionary Origins
of Life and Death
Pierre M. Durand
The University of Chicago Press Chicago and London
The University of Chicago Press, Chicago 60637
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ISBN- 13: 978- 0- 226- 74762- 0 (cloth)
ISBN- 13: 978- 0- 226- 74776- 7 (paper)
ISBN- 13: 978- 0- 226- 74793- 4 (e- book)
DOI: https:// doi .org /10 .7208 /chicago /9780226747934 .001 .0001
Library of Congress Cataloging- in-Publication Data
Names: Durand, Pierre M. (Pierre Marcel), author.
Title: The evolutionary origins of life and death / Pierre M.
Durand.
Description: Chicago : University of Chicago Press, 2021. |
Includes bibliographical references and index.
Identifiers: LCCN 2020024774 | ISBN 9780226747620 (cloth) |
ISBN 9780226747767 (paperback) | ISBN 9780226747934
(ebook)
Subjects: LCSH: Evolution (Biology). | Cytology. | Life—
Origin. | Apoptosis. | Death (Biology). | Biological fitness.
Classification: LCC QH366.2 .D865 2020 | DDC 576.8—dc23
LC record available at https:// lccn.loc .gov/ 2020024774
♾ This paper meets the requirements of ANSI/NISO Z39.48- 1992
(Permanence of Paper).
Contents
Foreword (by Eugene V. Koonin) vii
Preface ix
List of abbreviations xiii
An introduction to the scientific study of life and death 1
Part One: The origin of life
1 Philosophical considerations and the origin of life 9
2 The biotic world 17
3 The theory of life’s origins 25
4 Life at the very beginning I:
the chemistry of the first biomolecules 35
5 Life at the very beginning II:
the emergence of complex RNA molecules 43
6 The origin of life was an evolutionary
transition in individuality 49
7 A synthesis for the origin of life 61
Part Two: The origin of death
8 Philosophical considerations and the origin of death 73
9 Observations of death 83
10 Mechanisms and measures of programmed cell
death in the unicellular world 89
11 True PCD: when PCD is an adaptation 107
12 Ersatz PCD: the non- adaptive explanations for PCD 115
13 Programmed cell death and the levels of selection 121
14 A synthesis for the origin of programmed cell death 137
Part Three: Origins of life and death,
and their coevolution
15 Group selection and the origins of life and death 149
16 Life and death coevolution, and the emergence of complexity 155
Postface 169
Additional notes 172
Reference list 179
Index of names 209
Index of subjects 217
Foreword
by EugEnE V. Koonin
“In this world nothing can be said to be certain, except death and taxes.”
The second part of this famous quip by Benjamin Franklin, obviously, ap-
plies only to us humans. The first part is more general, we know full well
that all animals die, and so do plants, even if some, like redwoods, live
incredibly long by our standards. However, this is where most people to
some extent familiar with biology, and as far as I know, even most biol-
ogists draw the line: complex, multicellular organisms inevitably die but
simple, unicellular ones, such as protists (unicellular eukaryotes) and bac-
teria, are thought to be, at least, in principle, immortal. Surely, the unicel-
lular life forms perish massively, being killed by viruses, predators, starva-
tion, and all kinds of adverse environmental factors. The common belief,
though, is that they are not doomed to die in the same sense multicellular
organisms are. In The Evolutionary Origins of Life and Death, Pierre Du-
rand outlines a dramatic change to this perspective by synthesizing the
discoveries in biology over the last two decades that compellingly show
that most if not all unicellular life forms possess molecular mechanisms
for programmed cell death (PCD). The existence and importance of PCD
(often also called apoptosis, particularly in animals) in multicellular or-
ganisms is well known (in 2002, Sydney Brenner, H. Robert Horvitz, and
John E. Sulston were awarded the Nobel Prize in Physiology or Medicine
for the discovery of genes responsible for apoptosis in animals). Indeed,
in animals and plants, PCD is essential for defense against pathogens,
elimination of cells with impairments of the division cycle, and some de-
velopmental processes. Abrogation of PCD by somatic mutation leading
to cell immortalization results in cancer. However, conventional thinking
predicates PCD on multicellularity and separation of germline and soma:
some somatic cells are sacrificed to benefit the organism as a whole. From
this perspective, PCD in unicellular organisms appears puzzling, even par-
adoxical: what might be the benefit for a single cell organism to kill itself?
viii foreword
To explain PCD in unicellular life forms, a major shift in our under-
standing of evolution is required: group selection, i.e., selection that af-
fects ensembles of individuals, must be recognized as a key evolutionary
mechanism. If group selection is ubiquitous, so should be PCD: an en-
semble of cells will benefit from some of its members sacrificing them-
selves to prevent the spread of infection or to provide nutrients at times
of starvation. Should this be the case, one would have to conclude that
there are no strictly unicellular life forms but rather a continuum of co-
operation between cells, a striking realization in itself.
Group selection (also often referred to as inclusive fitness, a more tech-
nical term) has been for many years and remains a hotly debated subject
in evolutionary biology. Some prominent theorists flatly deny the very
existence of this phenomenon. And yet, the tide is turning, with multiple
lines of empirical data and theoretical argument converging to show, be-
yond reasonable doubt, that group selection is one of the defining factors
in the evolution of life. Indeed, in Durand’s book, group selection emerges
as a common denominator that unifies the origins of life and death, no
less. The earliest steps in the evolution of life cannot be modeled or even
reasonably imagined without selection affecting collectives of replicators,
that is, without the emergence of group selection. Furthermore, as dis-
cussed at some length in the book, the evolution of life is punctuated by
evolutionary transitions that involve changes in evolutionary individu-
ality, or in other words, transitions to new levels of selection (origin of
multi cellular life forms is the most obvious case in point, and it occurred
on multiple occasions in evolution). But, then, the same force that drove
the evolution of life, from its inception, promoted the evolution of PCD,
perhaps, concomitantly with the origin of the first cells, or at any rate,
shortly after. At later stages of evolution, PCD itself promoted the evo-
lution of complex organisms. The complete theory of group selection re-
mains an unresolved task, but Durand presents a simple but powerful
mathematical framework, based on the Price equation, to analyze this
crucial evolutionary phenomenon.
I think The Evolutionary Origins of Life and Death will be an eye opener
for many readers, biologists, and others interested in visiting the fron-
tiers of today’s conceptual thinking on evolution. This book, compact and
simple but densely packed with information and ideas, presents the new
edifice of evolutionary biology, a vibrant, progressing field that goes far
beyond the confines of neo- Darwinism.
Preface
This book deals with the origins and evolution of the first “living” mo-
lecular systems and the first “dying” cells. I have purposefully placed the
“living” and “dying” entities in quotation marks because their definitions
are not as clear as we would like them to be. Furthermore, a detailed ex-
amination of how the two phenomena originated and evolved reveals that
they are not always oppositional. They not only share some fundamental
processes that facilitated their origins, but also exhibit coevolutionary fea-
tures as more complex forms of life emerged.
With the advances and consolidation of research in the origins of life
and cell death fields, as well as a general interest in these subjects, the time
is right to organize these two areas into a single book. I hope that the sub-
ject material and integration of work and ideas from disparate disciplines
will be a source of interest to a variety of researchers, academics, and
scholars ranging from fundamental scientists in biology, physics, chemis-
try, evolution, and philosophy to students and perhaps even the lay public
with a background and interest in natural history. Many of the recent ad-
vances (for example, the genomic and experimental systems) and the in-
tegration of this information into syntheses of life and death, have not yet
found their way into general and evolutionary biology textbooks. I hope
the syntheses presented at the end of each part will be useful for tertiary
students. Most of the chapters should be accessible to those with a basic
but sound knowledge of general biology and natural history. There are,
however, a few sections and chapters that require much more detailed
knowledge of cell and molecular biology or evolutionary theory (for ex-
ample, chapters 6 and 13). For the non- specialists, these can be glossed
over or even ignored without interrupting the flow of the book or im-
pacting other chapters. At the same time, there may be some sections that
more expert readers may find frustratingly simple. These are necessary to
appeal to a more general science audience and I ask for your indulgence.
