Evolving Systems: January 2010 Core Group Meeting
January, 2010 Core Group Meeting
and Continuing Discussion
Deep Time and the Earth Sciences
Deep time is a concept that every geologist must grapple with in both research and teaching. The difference between the millions and billions of years of geologic evolution, as opposed to the centuries and millennia of human civilization is to say the least mind-bending. I have been thinking about geology in a significant way for nearly two decades and I still have trouble with the concept. In almost every way, change that occurs on our planet is incredibly slow, yet changes within our own cultures and lives changes almost daily. These differences in rate-process make it extremely difficult to talk in effective terms about the link between the human experience and our home planet – Mother Earth. Climate change, evolution, natural disasters, resource management – all of these incredibly important components of the human experience are fundamentally rooted in the Earth Sciences, yet to adequately explain the link between these two systems is often tenuous at best.
I will introduce and give some historical context for the concept of Deep Time through the perspective of the Earth sciences. I will also explore some of my own personal thoughts on what it means to be a passenger on a ship that is over 4.5 billion years old – that is a lot of zeros (4,500,000,000 years - billions, 1,642,500,000,000 days - trillions, 2,365,200,000,000,000 hours - quadrillion, or 141,912,000,000,000,000 seconds– quintillion).
Some relevant readings:
Gee, Henry, 1999. In Search of Deep Time: Beyond the Fossil Record to a New History of Life, Free Press, New York, 272 p.
Hazen, Robert M., 2001. Life's Rocky Start. Scientific American; April 2001, Vol. 284 Issue 4, p76, 10 p.
Knoll, Andrew, 2003. Life on a young planet, Princeton University Press, 304 p.
McPhee, John, 1982. Basin and Range, Farrar, Straus and Giroux, 216 p.
Valley, John W., 2005. A Cool Early Earth? Scientific American; October 2005, Vol. 293 Issue 4, p58, 8p.
Witze, Alexandra, 2006. The start of the world as we know it, Nature, Vol. 442, 128-131.
A meeting summary (Anne)
Arlo began his talk with a series of metaphors--the skin of the Eiffel Tower, the tip of the king's fingernail, the last moment of a year's calender--all functioning as reference frames intended to evoke the tiny portion of the earth's history in which humans have been present, and to represent the fundamental difficulty of trying to shift our thinking to a scale of time that is inconceivable: orders of magnitude larger than the one in which we "insignificant egomaniacs" operate on a daily basis. Arlo emphasized his difficulty, throughout, in thinking simultaneously about deep time and his own lived experience of time: his ability to grasp, but not fathom, what constitutes the difference. There is for him a "disconnect," an inability to "think in parallel" about scales that are so different.
He set the stage for this shift in scale by tracing the cumulative historical work of Nicolas Steno on "solid bodies within solids," of George Cuvier on catastrophism and extinction, of James Hutton on uniformitarianism, and of Charles Lyell on progressism
--culminating in the construction of "geologic columns" representing the successive ages of the earth. He also shared images of rock formations in the Grand Canyon, on Sitka Point in Scotland, and of zircon (the oldest known piece of material on earth) in Australia, to help us comprehend our place in what John McFee, in the 1970s, first called "deep time." We looked also @ images of Mt. Everest and Iowa, of the solar system and universe; we viewed maps ("ephemeral shots of the earth") of the long history of the amalgamation and collision of continents, the result of random motion of scattered small masses (short version: density drives continent emergence; scum floats).
We came to understand how very difficult it is to "get back to the early earth"; there are huge gaps in the record. Where does scientific rigor lie, for the geologist who has to speculate about what happened in the enormous time span that separates one strata of data from another? If not witnessed, can such changes be said to be "real"? There is "no way of testing"; "no one can go back and look." What is observable now are just correlative observations of stages in the geological record; there is no evidence of causation. Fossils are unique; we create a story to connect them with one another, and so concoct a progression. "This is not true science," Arlo said. (Or, several of us pushed back, does our definition of "what science is" need to change?) The belief system of Jehovah's Witnesses was also evoked here: imagining an entity alive for the whole time, seeing it all. Perhaps God "thinks in geological time," and is "a witness to all that has happened." This would be a "reason for creating God": to absorb these time scales.
In response to Arlo's presentation, our discussion circled first around the question of whether all human motivations mightn't vanish, when seen from a geological perspective: "On this time scale, nothing I do matters." In a tectonic, or even an evolutionary, framework, "nothing I do has an effect." Alternatively, might such an understanding give us a distanced perspective, make us less angry, more indifferent to petty human concerns, even bring us to ecstasy? Most biological evolution took place against a background of continual change. What difference might it have made, if that background were instead stable? Right now patterns continue to emerge, which are undetectable unless seen over longer spans.
Some of us thought that we could indeed think simultaneously in different scales, and usefully fuse them; others of us thought that a "sense of nothing happening" (over eons of earth's history) was an artifact of the way we differentiate using our own time scales: "nothing was waiting, but lots was happening." Sometimes we need both scales to make sense of things. We also thought together about a possible distinction between "formalistic," mathematical time and time experienced. Are we perhaps using the same word to describe two very different things? Can time exist only "formally," until experienced and used as part of one's life? "Formal time" and "time defined by events" may actually be two separate concepts, the latter marking time, which records change, in accord with human rates; the former...? Can we conceive of time in a way "that sees past time"? Mention was also made of the Yucca Mountain project, a system designed for nuclear waste, that tries to project methods of communication into the deep time of the future, vaster than we can process.
Thinking together about whether this story might be told "scientifically," or only in narrative, we thought "narrative implies time," whereas story is not time dependent. Is it necessary to use narrative to approach such a tale? Might we only be able to conceptualize deep time via metaphor? How else might we "imagine a time before imagining"? "What use" can we make of deep time? Can it be made conceivable to us by story? Is that the only way to understand it? Do we need non-linear ways to conceptualize such a process?
Several of us speculated that "filling in the interim" of what is not known, a process that is "necessarily never smooth," exists on all scales. Understanding what is going on in another's mind, or interpreting a poem--how do such gaps between what we know and what we don't differ from those presented by the phenomenon of deep time?
Continuing discussion (below)