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BIOL 1010 Introduction to Biology: The
Evolution and Diversity of Life. Spring 2011
Sections A & BSteve Thompson: [email protected]
http://www.bioinfo4u.net1
Wednesday, April 20, 2011
What the heck is Gaia?“The Gaia hypothesis is an ecological
hypothesis proposing that the biosphere and the physical components of the Earth
(atmosphere, cryosphere, hydrosphere and lithosphere) are closely integrated to form a complex interacting system that maintains
the climatic and biogeochemical conditions on Earth in a preferred homeostasis.”
http://en.wikipedia.org/wiki/Gaia_hypothesis 2
Wednesday, April 20, 2011
Where’s the word come from?Gaia was the Greek Goddess of the Earth itself,
mother to all the other Gods. It began with Chaos, the nothingness of space, then came Gaia, Nyx (Goddess of the night), Tartarus (God of the the Underworld), Erubus (God of darkness), and
Eros (God of sexual love).Gaia then created Uranus (God of the sky), Pontus
(God of the sea), and Ourea (God of the mountains). Gaia and Uranus conceived the twelve Titans, and six monsters (the three
Cyclops, and the three Hecatonchires).3
Wednesday, April 20, 2011
Uranus, shamed by the monsters, shoved them back into Gaia’s womb. In pain, Gaia pled with the Titans for help. The youngest, Cronus, took Gaia’s sickle and
castrated Uranus. Some of the blood and semen sprayed onto Gaia, spawning the Giants, the Furies,
and the Wood Nymphs. Uranus’ testicles were thrown to the sea, and Aphrodite arose.
Gaia’s mother role was not done. With other fathers, she gave birth to Antaeus, Ceto, Charybdis,
Creusa, Echidna, Erichthonius, Eurybia, Mimas, Nereus, Pheme, Phorcys, Python, Spercheus,
Thaumas, and Typhon.Or so at least one version of the mythology goes . . . .
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Gaia imagery
Wednesday, April 20, 2011
And what’s this got to do with Science?Well, James Lovelock and (later on)
Lynn Margulis (of endosymbiosis fame) appropriated the word to use for
the idea that all of the Earth, holistically as one entity, is a self-regulating system, that ‘attempts’ with feedback loop mechanisms, to maintain a preferred homeostasis
preferable for life, at large. 6
Wednesday, April 20, 2011
Initially the idea was scoffed, even by big wigs like Ford Doolittle, Stephen J. Gould, and Richard Dawkins (all my heros) as being teleological and too metaphysical, but
increasingly it has become more and more accepted, and is now often considered a
“theory” rather than a mere “hypothesis.”And more recent versions stress that Gaia is
not a ‘superorganism,’ but rather is an “emergent property of interaction among
organisms” (Margulis, 1998, Symbiotic Planet).7
Wednesday, April 20, 2011
Lovelock’s personal Webpage is quite unassuming.http://www.jameslovelock.org/
He first started thinking about this stuff back in the ‘60‘s when working with NASA on ways of detecting life on
Mars. It had to do with simple methods for analyzing the concentrations of gases, like oxygen and methane, on
other planets. He realized that life on Earth depended on the fact that surface temperatures have remained
somewhat constant despite the Sun’s increasingly hotter output, that the atmospheric composition has remained
quite constant, and that ocean salinity has remained very constant, all since life became well established on Earth!
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The granola-crunching, tree-hugging crowd, especially the ‘new-
age’ hippy sort took it and ran.And that’s where the trouble began. It got a very
bad name when all sorts of neo-pagan, Wiccan, and other mystical new-age theologies, latched on to it,
and embraced the idea of Earth as Goddess.Fortunately the scientific ecology movement
persevered and realized that a lot of what Lovelock had to say is quite true. And that humans have made a tremendous, and more than often not,
negative impact on Gaia! 9
Wednesday, April 20, 2011
This Website presents some aspects of the “Gaian Variations”
performance from 2004:http://www.gaianvariations.com/
learn/index.htm “Explore the Gaia hypothesis” at the site.
It summarizes many of the concepts we’ve covered in this Ecology component
of the course, as well as some of the earlier concepts.
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And Dr. Stephan Harding has a ten part series on YouTube. We won’t take the time to see all
these, but if this stuff interests you, I certainly encourage that
you check it out.http://www.youtube.com/watch?v=523bXlK5t34
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Now let’s hear what Lovelock has to say about Gaia himself.
http://www.nature.com/nature/videoarchive/lovelock/ As you’re watching the video, give me your thoughts on Gaia, on
paper, as an in-class assignment. Tell me what it is, where the word came from, why it got such a bad reputation, and why it is now
slowly being embraced as a valid scientific theory. This is due at the end of class today, no exceptions!
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