While this work over-focuses on supposed early symbioses in life, it is interesting for its view in how symbiogenesis, not genetics, is the primary factor in generating new species, and also how the ecosystem works together as a cooperative whole to make life on earth possible.

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Product Description

Named "best biology book of the year" by Library Journal, Symbiotic Planet describes how symbiosis is the key to understanding the origins of cells, the evolution of sex, the emergence of life on land, and even the physiology of our planet.

"Autobiographical, passionate, argumentative." -Kirkus Reviews

In Symbiotic Planet Lynn Margulis shows that symbiosis, which simply means members of different species living in physical contact with one another, is crucial to the origins of evolutionary novelty. Ranging from bacteria to the living Earth itself, Margulis explains the symbiotic origins of many of evolution's most important innovations.

Along the way, Margulis describes her initiation into the world of science and the early steps in the present revolution in evolutionary biology and the importance of species classification for how we think about the living world. Written with enthusiasm and authority, this is a book that could change the way you view our living Earth.

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Product Details

• Amazon Sales Rank: #159860 in Books
• Published on: 1999-10-07
• Original language: English
• Number of items: 1
• Binding: Paperback
• 176 pages

Features

• ISBN13: 9780465072729
• Condition: NEW
• Notes: Brand New from Publisher. No Remainder Mark.
• Click here to view our Condition Guide and Shipping Prices

From Publishers Weekly
From the origin of life to the classification and phylogeny of living organisms, from a discussion of GaiaAthe belief that Earth operates like a living beingAto a discussion of the underlying reasons for sex, iconoclastic biologist Margulis (coauthor, What Is Sex?, etc.) takes on many of the big questions in biology in this small, rambling and informal tract. In a book that is part autobiography and part biological primer, MargulisAthe scientist most responsible for the theory that animal and plant cells originally arose by combining with simple bacteriaAadvances the idea that a large part of organic evolution can be explained by symbiosis, "the living together in physical contact of organisms of different species." Rather than convincing readers of this theory, however, she seems content to lavish most of her attention on basic biological concepts. While Margulis conveys a sense of the wondrous and intricate origins of life, many of the issues she touches upon here are more clearly and comprehensively dealt with in her other works. 11 b&w illustrations.
Copyright 1998 Reed Business Information, Inc.

From Library Journal
For 30 years, the Gaia theory of life on Earth has remained vital, dynamic, and controversial. One of its leading advocates provides a synthesis and overview of the current status of the theory, plus a few important new ideas of her own.
Copyright 1999 Reed Business Information, Inc.

From Scientific American
Gracing her tale with personal touches and with lines from the poems of Emily Dickinson as chapter headings, Margulis describes the development of her theory of symbiosis and ponders how it relates to the Gaia concept of a living Earth. "No species existed before bacteria merged to form larger cells including ancestors to both plants and animals," she writes. "The permanent incorporation of bacteria inside plant and animal cells as plastids and mitochondria is the part of my serial endosymbiosis theory that now appears even in high school textbooks. But the full impact of the symbiotic view of evolution has yet to be felt. And the idea that new species arise from symbiotic mergers among members of old ones is still not even discussed in polite scientific society." The Gaia concept is that aspects of Earth's atmospheric gases and surface rocks and water are regulated by the growth, death, integration and other activities of living organisms. Gaia, Margulis says, "is a convenient name for an Earthwide phenomenon: temperature, acidity/alkalinity, and gas composition regulation"through the series of interacting ecosystems that compose a single huge ecosystem at Earth's surface. How do symbiosis and the Gaia concept relate to each other? Greg Hinkle, once Margulis's student and now a professor at the University of Massachusetts, provides an answer that Margulis likes: "Gaia is just symbiosis as seen from space."

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Customer Reviews

Especially recommended for Margulis fans but not her best
I am a great admirer of the author, who is one of the most creative biologists alive today, and a tireless popularizer of the brilliant and exciting ideas that define her career. For fans like me, this book is a must, as it offers tidbits about the author's life, including her marriage to Carl Sagan. It is also valuable in that it seeks to respond to criticisms of the Gaia hypothesis. But for those new to Margulis' work, I would recommend starting with Microcosmos, which she wrote with her son Dorion Sagan, a truly wonderful book that everyone interested in biology or the environment should have on their shelves. If Microcosmos doesn't grab you, don't bother with Symbiotic Planet. If it does grab you, then you'll probably want to go on to this book and others by Margulis.

The autobiography of an idea
Some years ago, Margulis promoted a new concept in evolution. Complex life developed from the merging of microbial forms of life. Elements of the cell such as mitochondria, chloroplasts and other organelles came from small, simple lifeforms invading larger cells. The idea was a long time in gaining acceptance, but is now part of conventional evolutionary texts. In this book, she expands her earlier work with some accounts of her life as a scientist and wife of Carl Sagan. She also goes beyond her earlier work to advance a new thesis on the accelerator of evolution - sex. While many of her ideas are presented in more detail elsewhere, this book is a good, quick introduction to fuller accounts of her thinking.

Margulis is an innovator - forceful in imparting her ideas. She portrays herself as a rebel from early in her career, arguing here that she was sceptical of "genes in the nucleus determin[ing] all the characteristics of plants and animals." Her misgivings received scant support, however, without a replacement thesis. She found one in symbiosis - the association of multiple organisms. It took many years of investigation, including initial rejection of her attempts to publish, before the idea of SET [Serial Endoymbiosis Theory] found acceptance. So much attention had been focussed the DNA in the cell nucleus that organelle structure and function had been essentially overlooked as irrelevant. That these organelles might have been independent organisms at some point was too novel. Her account of the struggle to gain recognition is related as one of dogged persistence, nearly devoid of outside support .

Moving through an interesting discussion of life's origins, she dismisses the notion that forms of nucleic acids arose before simple cells. She finds the natural occurence of lipids [fats] as the more likely precursors of complex life, with RNA and DNA arising as a way to give these fat globules more survival ability. As with her earlier thesis, this one will generate controversy, something Margulis seems nutured on.

Her proposal about the emergence of sex will come as a surprise to most readers. In a word, she suggests sex resulting from cannibalism. In Margulis' view, certain microbes under stress, notably the absence of food, turned on each other for survival. The cannibalism was not always fully consummated, she suggests, but the beginnings of mixing genetic material was begun in the process. Incomplete cannibalism could lead to the formation of a new, more complex organism. If this process occurred often enough within a compatible group, the new organism, obviously larger than its predecessors, would be more fit to compete.

In conclusion, Margulis makes a strong case in favour of James Lovelock's Gaia concept. This might have been a non-sequitor in the hands of someone less able to deal with novel ideas. Margulis stresses that Gaia has been mistakenly viewed as Earth's biosphere acting as a single organism. She argues that Gaia really means a global network - a "system of organisms." The Gaia concept means the elements of the "system" are tightly entangled and extinctions weaken the structure. If the extinction rate exceeds the rate of recovery the system is endangered. It's interesting to note in light of her definition that the Gaia website still refers to it as a "superorganism," not a "system of organisms." This disparity doesn't detract from Margulis' presentation, which is admirably presented. She offers enough graphic support for the text to clarify or enhance her themes. In all, this is a fine mind-opener in thinking about the development of early life. Readable by anyone interested in life's history and processes.

Excellent summary with a few flaws
Readable in a few hours, this book gives a quick introduction to a concept tremendously important to understanding the evolution on life on earth. I would have liked more extensive discussion of SET, with respect to the protoctists; the recognition of the development of these organisms from the symbiosis of various bacteria laid the groundwork for the understanding of symbiotic relationships in plants, animals, and fungi, which Margulis discusses in later chapters, yet the details of it take only a couple early chapters. Other volumes in this series are longer (some 170 pp.), and this one could have been, too. The clarification of "the Gaia hypothesis," in the last chapter, is very strong, and welcome; undergirding it is Margulis's insistence (throughout the book) on unsentimental and rigorous scientific thinking. The book does contain flaws. Editorial errors show a lack of careful proofreading (e.g., the date of the rediscovery of Mendel's work is given as 1990). Many sentences would have benefitted from more use of commas. More illustrations (e.g., of the structures of cells and organelles, mitosis, and meiosis) and summary equations for various metabolic processes, as well as a glossary, would make the book more accessible and useful to those who retain only a hazy knowledge (and that probably out-dated) of these things. Finally, Margulis takes too much the stance of the battered, then embraced and finally vindicated iconoclast, and seems rather too smug (as when she refers to "my SET theory"). It's just not attractive, and could have been toned down; it's obvious that she's brilliant. My criticisms, however, are relatively minor, and I recommend this book enthusiastically.