BIOL 1010 Introduction
to Biology: The
Evolution and Diversity
of Life. Spring 2011
Sections A & B
Steve Thompson: stthompson@valdosta.edu
http://www.bioinfo4u.net
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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
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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 Under world), 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
t welve Titans, and six monsters (the three
Cyclops, and the three Hecatonchires).
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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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Wednesday, April 20, 2011
Gaia imagery
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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 selfregulating system, that ‘attempts’
with feedback loop mechanisms, to
maintain a preferred homeostasis
preferable for life, at large.
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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 ‘s uperorganism,’ but rather is an
“emergent property of interaction among
organisms” (Margulis, 1998, Symbiotic Planet).
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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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Wednesday, April 20, 2011
The granola-crunching, treehugging crowd, especially the ‘newage’ 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!
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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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Wednesday, April 20, 2011
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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Wednesday, April 20, 2011
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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Wednesday, April 20, 2011