John Brockman in Edge:
Biologist Lynn Margulis died on November 22nd. She stood out from her colleagues in that she would have extended evolutionary studies nearly four billion years back in time. Her major work was in cell evolution, in which the great event was the appearance of the eukaryotic, or nucleated, cell — the cell upon which all larger life-forms are based. Nearly forty-five years ago, she argued for its symbiotic origin: that it arose by associations of different kinds of bacteria. Her ideas were generally either ignored or ridiculed when she first proposed them; symbiosis in cell evolution is now considered one of the great scientific breakthroughs.
Margulis was also a champion of the Gaia hypothesis, an idea developed in the 1970s by the free lance British atmospheric chemist James E. Lovelock. The Gaia hypothesis states that the atmosphere and surface sediments of the planet Earth form a self- regulating physiological system — Earth's surface is alive. The strong version of the hypothesis, which has been widely criticized by the biological establishment, holds that the earth itself is a self-regulating organism; Margulis subscribed to a weaker version, seeing the planet as an integrated self- regulating ecosystem. She was criticized for succumbing to what George Williams called the “God-is good” syndrome, as evidenced by her adoption of metaphors of symbiosis in nature. She was, in turn, an outspoken critic of mainstream evolutionary biologists for what she saw as a failure to adequately consider the importance of chemistry and microbiology in evolution. I first met her in the late 80's and in 1994 interviewed her for my book The Third Culture: Beyond the Scientific Revolution (1995). Below, in remembrance, please see her chapter, “Gaia is a Tough Bitch”. One of the compelling features of The Third Culture was that I invited each of the participants to comment about the others. In this regard, the end of the following chapter has comments on Margulis and her work by Daniel C. Dennett, the late George C. Williams, W. Daniel Hillis, Lee Smolin, Marvin Minsky, Richard Dawkins, and the late Francisco Varela. Interesting stuff.