"For more than a billion years, the only life on this planet consisted of bacterial cells, which, lacking nuclei, are called prokaryotes, or prokaryotic cells. They looked very much alike, and from the human-centered vantage point seem boring. However, bacteria are the source of reproduction, photosynthesis, movement — indeed, all interesting features of life except perhaps speech! They're still with us in large diversity and numbers.
They still rule Earth.
Symbiosis has nothing to do with cost or benefit. The benefit/cost people have perverted the science with invidious economic analogies. The contention is not over modern symbioses, simply the living together of unlike organisms, but over whether "symbiogenesis" — long-term symbioses that lead to new forms of life — has occurred and is still occurring. The importance of symbiogenesis as a major source of evolutionary change is what is debated. I contend that symbiogenesis is the result of long-term living together — staying together, especially involving microbes- -and that it's the major evolutionary innovator in all lineages of larger nonbacterial organisms.
......animals are very tardy on the evolutionary scene, and they give us little real
insight into the major sources of evolution's creativity.
The Gaia hypothesis is a biological idea, but it's not human-centered. Those who want Gaia to be an Earth goddess for a cuddly, furry human environment find no solace in it. They tend to be critical or to misunderstand. They can buy into the theory only by misinterpreting it. Some critics are worried that the Gaia hypothesis says the environment will respond to any insults done to it and the natural systems will take care of the problems. This, they maintain, gives industries a license to pollute. Yes, Gaia will take care of itself; yes, environmental excesses will be ameliorated, but it's likely that such restoration of the environment will occur in a world devoid of people.
Lovelock would say that Earth is an organism. I disagree with this phraseology. No organism eats its own waste. I prefer to say that Earth is an ecosystem, one continuous enormous ecosystem composed of many component ecosystems. Lovelock's position is to let the people believe that Earth is an organism, because if they think it is just a pile of rocks they kick it, ignore it, and mistreat it. If they think Earth is an organism, they'll tend to treat it with respect. To me, this is a helpful cop-out, not science. Yet I do agree with Lovelock when he claims that most of the things scientists do are not science either. And I realize that by taking the stance he does he is more effective than I am in communicating Gaian ideas.
Gaia is a tough bitch — a system that has worked for over three billion years
without people. This planet's surface and its atmosphere and environment will
continue to evolve long after people and prejudice are gone.
Extracts truffled from Gaia is a Tough Bitch, read full interview with LM at The Edge
LYNN MARGULIS in her life and times was a biologist; Distinguished University Professor in the
Department of Biology at the University of Massachusetts at Amherst; author of
The Origin of Eukaryotic Cells (1970), Early Life (1981), and
Symbiosis in Cell Evolution (2d ed., 1993). She is also the coauthor,
with Karlene V. Schwartz, of Five Kingdoms: An Illustrated Guide to the Phyla
of Life on Earth (2d ed., 1988) and with Dorion Sagan of Microcosmos
(1986), Origins Of Sex (1986), and Mystery Dance (1991).
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