Symbiotic Planet - Softcover

Margulis, Lynn

Softcover

ISBN 10: 0465072720 ISBN 13: 9780465072729

Publisher: Basic Books, 1999

Synopsis

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.

About this title

About the Author

Lynn Margulis, Distinguished Professor in the Department of Geosciences at the University of Massachusetts at Amherst, has been a member of the National Academy of Sciences since 1983. She is best known for her pathbreaking work on the bacterial origins of cell organelles and for her collaboration with James Lovelock on Gaia theory. Her previous books include Symbiosis in Cell Evolution; Five Kingdoms (with K. V. Schwartz); and (with Dorion Sagan) Origins of Sex, Garden of Microbial Delights, What Is Life?, What Is Sex?, and Slanted Truths: Essays on Gaia, Symbiosis and Evolution.

From Kirkus Reviews

Let's hear it for the bugs not your creepy-crawlies, but bacteria, the be-all (and possible end-all) of life on Earth, according to Margulis. Here she describes the once radical theory that cells have incorporated bacteria to mutual advantage and uses that as a springboard to summarize a still more radical theory of how species evolve. She calls it serial endosymbiosis theory (SET). It is now conventional wisdom that the energy-producing mitochondria in animal cells were once free-living bacteria. Indeed, they have their own genesdifferent from nuclear DNA. Margulis provides many examples of fruitful symbioses, including sexual union itself as the merger of sperm and egg cells. According to SET, there are successive steps or mergers that led to multicellular life forms: In steps one and two the oldest bacterial formsthe non-oxygen breathing ``archaebacteria'' found in deep ocean ventsmerged with swimming bacteria two billion years ago to form the nuclear heart of animal, plant, and fungal cells and provide the cilia for swimming. Later steps introduced a third partner able to breathe oxygen and added the ability to engulf and digest food (phagocytosis). The last step involved engulfing yet another bacteriumbut one these various new forms of life could not digest: bright green photosynthetic bacteria. The bone of contention here is the origin of ciliated cellscritical to evolution for their vital role as sperm tails, among other things. Margulis has a theory about their origin, but as they say, more research is needed. Margulis's theory also dictates a change in taxonomy to five kingdoms: bacteria at the base, then ``protoctists'' (algae, slime molds, ciliates) next, and then animals, plants, and fungi. Finally, she defends Lovelock's Gaia theory, which she interprets to mean that enormous interacting ecosystems on Earth achieve homeostasis rather than that the planet is in the hands of some benign Mother Earth. This is vintage Margulispersonal, autobiographical, passionate, argumentative, at times over the top, but full of ideasat least some of which, in the past, have proved to be right. -- Copyright ©1998, Kirkus Associates, LP. All rights reserved.

About this edition

• Publisher: Basic Books
• Publication date: 1999
• ISBN 10: 0465072720
• ISBN 13: 9780465072729
• Binding: Paperback
• Number of pages: 155