Page 11: At first we explained Gaia as... "Life, or the biosphere, regulates or maintains the climate and atmospheric composition at an optimum for itself." Neither Lynn or myself have proposed that ...self-regulation is purposeful, [but criticism!]

15: "Reductionist": a bottom-up view: that assumes that the whole is never more than the sum of its parts, and that by taking things to pieces, we can find out how they work.

36: One of the great rewards of science is that sudden flash of understanding that comes when holism and reduction meet.

17: I find myself looking at the Earth as a place for worship, with all life as its congregation.

20: Nothing teaches better than a near-miss. The essence of living green, of being a citizen of Gaia, is not a fretful puritanism. If we can think of ourselves as a part of a giant living organism and perhaps even as a cause of its indigestion, then we may be guided to live within Gaia in a way that is seemly and healthy. Even thinking this way is an antidote...

31: I respect the views of those with faith who find comfort in a church, and who say their prayers, but acknowledge that they cannot, by logic alone, convince themselves, or others, of their reason for believing in God. Similarly, I respect those who take comfort from the natural world and who may wish to say their prayers to Gaia.

56: Gaia is the planetary life system that includes everything influenced by and influencing the biota. ... the capacity for homeostasis...

96: All organisms change their environs thru their life- chemistry. ...[as Daisyworld shows] the pressures of selection can act in favor of those organisms with a tendency to create changes that improve their environs.

99: Bacteria have made, and will make up. so long as organic life persists, the greater part of life on Earth. They play the largest role in sustaining Gaia. In sediments... they make up a significant part of total mass.

100: All bacteria share a common feature: they have a prokaryotic cell structure. Much simpler. Cell with cytoplasm, but no nucleus, no organelles. A single chromosome coiled at its center.

101: Lynn Margolis is distinguished as the proponent of the Endo-symbiosis Hypothesis, a view that I find extremely compelling. In this hypothesis, the [eukaryotic] cells of all the more recent life on Earth are made up from ensembles of smaller organisms that were once free-living. Our own cells... contain small bodies called mitochondria. These provide the power we need to live. ...[ it, and many others are...] genetically quite different from the genetic material of the cell nucleus. I find this convincing evidence for her view that these organelles were once separate and free organisms. Endo-symbiosis began when consumers ingested other bacteria--or were invaded by--other bacteria. ...usually fatal, but once in a while, instead, a truce was called and they lived together in symbiosis, as each benefitted from the other's presence.

106: Natural selection would have favored organisms whose collective effect was to improve the environment, and/or capitalize on the environmental changes caused by other organisms. The balance of [gases], ...salinity... rate of formation of soil--all are so closely woven into the evolutionary patterns of living organisms as to form a single, changing tapestry.

108: In the early 80's, I published papers proposing that the presence of organisms in the soil greatly enhances the rate of rock weathering. In fact, was 1,000 times faster in the presence of organisms than with sterile rock.

129: There's a constant input of cloride ions to the sea... from rivers and volcanoes. A rate such that ocean salinity would reach the critical 5% salt level in about 800 Million yrs. ...one quarter of the time life's been here. The persistence suggests that the limit has not been exceeded. Where does it go? Evaporite deposits. [in lagoons perhaps made by microbial mats].

131: The fall of rain is so great that it's enough to fill the oceans in only 60,000 yrs. The rate of erosion on the land by the rain is so rapid that sufficient solid material to fill the ocean basins would be brought down in 17 Million yrs. ...may seem a long time , it's only 1/300th the age of Earth. [ They] do not fill up because uplift removes the accumulating materials, or they're dragged below... by the movement of the plates.

*132: The soil has an atmosphere all its own, with CO2 30 times more abundant than in the free air, and CH4 and NO greatly enriched.

*136: gases that have 3 or more atoms--CO2, H2O--can absorb Infra-red radiation because they naturally vibrate at the same frequencies as the IR. Like a TV antenna.

*144: Perhaps the dinos died, not directly from the impacts, but because they couldn't compete in the changed and hotter world. which lastd for a half to one million yrs.

*146: [There is a] complication from the fact that by far the most important of the green-house gases is water vapor. It's the most abundant--10K ppm... {=10 per K, = 1 per 100, or 1% average]. It's the source of most of gaseous global heating. It acts, in a way, to amplify the effect of other green-house gases. [When CO2 heats the world, more water vapor can be carried in the air. A vicious circle!]
On the land surfaces in the temperate regions, the coniferous forests act like dark daisies, with the effect of extending the growing season deeper into the winter. ...Its shape has evolved to shed snow, absorb sunlite and warm the region.

*148: As the sun increases heat [over millions of years] Gaia has to maintain ever-lower levels of CO2 to keep comfortably cool. 180 ppm in glaciations. 280 in inter-glaciations. We are close to the lower limit at which plant life can survive. It has created the evolutionary pressure for new types of plants that are able to grow at lower levels. About 10 Million yrs ago, they did. C4 plants evolved. That refers to different types of carbon metabolism. It includes most grasses.
This success staves off, but does not prevent, the ultimate failure of the present cooling mechanism. Within 100 million yrs, the sun'll be warm enough to require zero CO2 to maintain temperature norms. The system will then have to shift to new set of parameters.

*154: As individuals, or as small groups hunting and gathering, we once lived in symbiosis with our planet. When we began using fire, tools and agriculture, we became more dependent on each other socially, and also more powerful and numerous. We had the potential to sustain our own environment at the expense of the Earth; to break our contract with Gaia. At first, the breaches were mild, just the wearing of clothing, and houses. Herd, grow plants. But right up to the beginning of this century, none of this, nor the industrial civilizations that had evolved, were significant in themselves to the Earth. The danger lay in the potential for further development. Now the consequences threaten both us and our planet.
The first stage of population growth --when food is sufficient-- often takes the form mathmaticians call exponential: "The rate of increase is proportional to numbers present. e.g.: imagine a pond on whose surface a water lily is growing, and spreading so as to double its leaf area daily. It's taken 19 days to cover half the pond's surface. How long before the pond is entirely covered? NOT 19 days; ONE. Growth never follows an exponential course indefinitely; houseflies would soon exceed the weight of the Earth. The real relationship is closer to what's called logistic: exponential at first, then slowing to zero-growth at steady state. This can mean that the death rate rises to meet the birth rate, as environmental constraints on the population come into play. We humans must be close to that 19-day period... so far as our coverage with crops. As Malthus foresaw, the human population is outstripping its food supply and environment, and must in the end be curtailed--by famine, disease, war, or natural catastrophy. Malthus' predictions are coming true at last. The statement "there's no pollution but people" carries an awful truth.

*160: Emissions of sulphur gasses by the ocean algae are probably rising too, as a result of the extra nutrients washing from farmer's fields down the rivers to the North Sea....causing blooms in the enriched waters. The fact is that farming, by increasing marine sulphur emissions, may be a cause of acid rain. seems to be an unwelcome truth.

*169: CO2 contributes 49% of warming. CH4 (methane)18. CFCs 14. NO (nitrogen oxides) 6. Effectiveness, relatively: 1. 25. 10,000. 150. [You see that CFCs, while tiny in volume, are efficient in the extreme!]

*176: In Africa, it's not overpopulation with people, but with livestock. [Welll... who grows them? ] About 27+ Million deaths from famine there in 1991. The human and natural ecosystems of that unhappy continent may soon disintegrate.

*177: I've made a strong statement rejecting the idea of planetary management, insofar as it implies taking charge of the Earth. I propose instead that we learn to live with the Earth as part of it; by managing ourselves, and by humbly taking and giving the gifts that sustain [us]. How can we manage it, if we don't know what it is? [jkh: if you had to control kidneys, heart, lungs, etc; steda being automatic. ]

*178: "Spaceship Earth", as if the time that life has existed on Earth were just a prelude to the evolution of humans, and to serve as their life-support system when they chanced to come aboard.

*182: calculations of the net production of O2 by the [Amazon] forest gave an answer close to zero. [same for use as CO2 sink.] but great air-conditioner. [jkh: I've a problem with that, if he means it's a coolant. The only net cooling possible (without orbiting parasols) is greater albedo (all wavelengths, including IR). All else just moves heat around.]

*186: Could we, by some act of common will, change our natures and become proper stewards, gentle gardeners taking care of all of the natural life of our planet? We're all too plainly failing even to manage ourselves and our own institutions. I would sooner expect a goat [to do it.] ... a hopeless task-- to be made forever accountable for the smooth running of the climate, the composition of the oceans, the air, the soil. Something that, until we began to dismantle creation, was the free gift of Gaia.
We are better as shop stewards; representatives. People should be living in union with the other members, not exploiting them and their habitats. ...we must learn to live with the Earth in partnership. Otherwise, [only] the rest will. As part of Gaia, unconsciously move the Earth to a new state, one where we humans may no longer be welcome.