Symbiosis As A Source Of Evolutionary Innovation

These original contributions by symbiosis biologists and evolutionary theorists address the adequacy of the prevailing neo-Darwinian concept of evolution in the light of growing evidence that hereditary symbiosis, supplemented by the gradual accumulation of heritable mutation, results in the origin of new species and morphological novelty.A departure from mainstream biology, the idea of symbiosis--as in the genetic and metabolic interactions of the bacterial communities that became the earliest eukaryotes and eventually evolved into plants and animals--has attracted the attention of a growing number of scientists.These original contributions by symbiosis biologists and evolutionary theorists address the adequacy of the prevailing neo-Darwinian concept of evolution in the light of growing evidence that hereditary symbiosis, supplemented by the gradual accumulation of heritable mutation, results in the origin of new species and morphological novelty. They include reports of current research on the evolutionary consequences of symbiosis, the protracted physical association between organisms of different species. Among the issues considered are individuality and evolution, microbial symbioses, animal-bacterial symbioses, and the importance of symbiosis in cell evolution, ecology, and morphogenesis. Lynn Margulis, Distinguished Professor of Botany at the University of Massachusetts at Amherst, is the modern originator of the symbiotic theory of cell evolution. Once considered heresy, her ideas are now part of the microbiological revolution. ContributorsPeter Atsatt, Richard C. Back, David Bermudes, Paola Bonfante-Fasolo, René Fester, Lynda J. Goff, Anne-Marie Grenier, Ricardo Guerrero, Robert H. Haynes, Rosmarie Honegger, Gregory Hinkle, Kwang W. Jeon, Bryce Kendrick, Richard Law, David Lewis, Lynn Margulis, John Maynard Smith, Margaret J. McFall-Ngai, Paul Nardon, Kenneth H. Nealson, Kris Pirozynski, Peter W. Price, Mary Beth Saffo, Jan Sapp, Silvano Scannerini, Werner Schwemmler, Sorin Sonea, Toomas H. Tiivel, Robert K. Trench, Russell Vetter

The monograph examines the evolution of microorganisms and the importance of symbiosis as a mechanism of evolution. Initial chapters discuss serial endosymbiosis theory, diversity, and cell evolution in perspective. The period from prebiotic times through the development of symbiosis is examined in chapters about the Earth before cells, evolution before oxygen, atmospheric oxygen from photosynthesis, and symbiogenesis. Symbiotic evolution is examined in chapters about nuclei, mitosis, and undulipodia; undulipodia from spirochetes; mitochondria; and plastids. The work is summarized with a look at consequences of these theories in the Phanerozoic era.

The history of life is a nearly four billion year old story of transformative change. This change ranges from dramatic macroscopic innovations such as the evolution of wings or eyes, to a myriad of molecular changes that form the basis of macroscopic innovations. We are familiar with many examples of innovations (qualitatively new phenotypes that provide a critical benefit) but have no systematic understanding of the principles that allow organisms to innovate. This book proposes several such principles as the basis of a theory of innovation, integrating recent knowledge about complex molecular phenotypes with more traditional Darwinian thinking. Central to the book are genotype networks: vast sets of connected genotypes that exist in metabolism and regulatory circuitry, as well as in protein and RNA molecules. The theory can successfully unify innovations that occur at different levels of organization. It captures known features of biological innovation, including the fact that many innovations occur multiple times independently, and that they combine existing parts of a system to new purposes. It also argues that environmental change is important to create biological systems that are both complex and robust, and shows how such robustness can facilitate innovation. Beyond that, the theory can reconcile neutralism and selectionism, as well as explain the role of phenotypic plasticity, gene duplication, recombination, and cryptic variation in innovation. Finally, its principles can be applied to technological innovation, and thus open to human engineering endeavours the powerful principles that have allowed life's spectacular success.

Our evolution and that of all plants and animals is not thought to be due solely to the gradual accumulation of gene changes within species. Symbiosis is at the root of our being. This book is a systematic history of this emerging field and gives an account of the growth of a biological idea.

Although Charles Darwin's theory of evolution laid the foundations of modern biology, it did not tell the whole story. Most remarkably, The Origin of Species said very little about, of all things, the origins of species. Darwin and his modern successors have shown very convincingly how inherited variations are naturally selected, but they leave unanswered how variant organisms come to be in the first place. In Symbiotic Planet, renowned scientist Lynn Margulis shows that symbiosis, which simply means members of different species living in physical contact with each other, is crucial to the origins of evolutionary novelty. Ranging from bacteria, the smallest kinds of life, to the largest -- the living Earth itself -- Margulis explains the symbiotic origins of many of evolution's most important innovations. The very cells we're made of started as symbiotic unions of different kinds of bacteria. Sex -- and its inevitable corollary, death -- arose when failed attempts at cannibalism resulted in seasonally repeated mergers of some of our tiniest ancestors. Dry land became forested only after symbioses of algae and fungi evolved into plants. Since all living things are bathed by the same waters and atmosphere, all the inhabitants of Earth belong to a symbiotic union. Gaia, the finely tuned largest ecosystem of the Earth's surface, is just symbiosis as seen from space. Along the way, Margulis describes her initiation into the world of science and the early steps in the present revolution in evolutionary biology; the importance of species classification for how we think about the living world; and the way "academic apartheid" can block scientific advancement. Written with enthusiasm and authority, this is a book that could change the way you view our living Earth.

In this comprehensive history of symbiosis theory--the first to be written--Jan Sapp masterfully traces its development from modest beginnings in the late nineteenth century to its current status as one of the key conceptual frameworks for the life sciences. The symbiotic perspective on evolution, which argues that "higher species" have evolved from a merger of two or more different kinds of organisms living together, is now clearly established with definitive molecular evidence demonstrating that mitochondria and chloroplasts have evolved from symbiotic bacteria. In telling the exciting story of an evolutionary biology tradition that has effectively challenged many key tenets of classical neo-Darwinism, Sapp sheds light on the phenomena, movements, doctrines, and controversies that have shaped attitudes about the scope and significance of symbiosis. Engaging and insightful, Evolution by Association will be avidly read by students and researchers across the life sciences.

The Arthur M. Sackler Colloquia of the National Academy of Sciences address scientific topics of broad and current interest, cutting across the boundaries of traditional disciplines. Each year, four or five such colloquia are scheduled, typically two days in length and international in scope. Colloquia are organized by a member of the Academy, often with the assistance of an organizing committee, and feature presentations by leading scientists in the field and discussions with a hundred or more researchers with an interest in the topic. Colloquia presentations are recorded and posted on the National Academy of Sciences Sackler colloquia website and published on CD-ROM. These Colloquia are made possible by a generous gift from Mrs. Jill Sackler, in memory of her husband, Arthur M. Sackler.

Symbioses and Stress examines how organisms in tight symbiotic associations cope with abiotic and biotic stress. Presenting new findings on symbioses by experts and leading scholars in the field, this volume complements courses and lectures in biology and genetics.