[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: mass extinctions and technology



some final thoughts...

> From: Mark Harvey [mailto:mharvey@scu.edu.au]
>
> On your side you have the waste of our civilization, and the expertise of
> its paleontologists and archaeologists.  On my side, the brevity of our
> civilization in geologic terms,  entropy, and the immensity of geologic
> time it acts upon.   Only Aktuopaleontologie will allow us to be
> objective
> in an estimation of probability.

Fair enough.

Actually, to line up some of the potentials of preservation vs. lack
thereof:

Factors favoring macro- and microscopic evidence of hypothetical pre-human
civilizations responsible for mass extinctions:
* Numbers (technology allows numbers to greatly increase, allows for
spreading over vast regions beyond original homeland)
* Environmental effects (horrendously vast amounts of trash produced,
chemical tracers produced, technologically produced "trace fossils",
depletion of natural resources, modification of other life forms and
conversion of large parts of the biomass to feeding increasing numbers,
global taxonomic homogenization)
* Mass extinctions are stratigraphic intervals which are preferentially
studied by modern researchers, so that these are sought out over other parts
of the stratigraphic record and subject to more fine-scale examinations
* Duration of technological species (unknown at present, given our current
small sample size; however, one could reasonably argue that a disastrously
environmentally unfriendly species would have a short species duration, the
survivors might retain enough knowledge of the technology to "recolonize"
the world after a few millenia)
* The present "mass extinction" does not in fact match your typical
pre-Quaternary mass extinction events (at least not yet).  All the previous
ones were characterized first and foremost by the extinction of diverse
clades of easily preservable, previously abundant marine invertebrates: at
present none of these are represented in the victims of the Quaternary
extinctions.  (However, it would not be unreasonable to suspect a severe
enough treatment of the oceans might produce a loss of the modern
scleractinian coral reef system, which WOULD duplicate at least some of
these effects).

Factors against such preservation:
* Duration of technological species (unknown at present, given our current
small sample size;  however, one could reasonably argue that a diastrously
environmentally unfriendly species would destroy itself past the point of
recovery in the space of only a few millenia)
* While the K/T boundary is studied around the globe from a variety of both
marine and terrestrial paleoenvironments, not all such boundaries are
equally well examined at present (for example, the Cenomanian-Turonian
extinctions)
* Niven's solution: a PHC might not have inhabited a region condusive to
preservation (i.e., plate margins, oceanic depths, etc.). (A side note: the
LONNNNGGG scale environmentalist ethic of the civilizations in David Brin's
Uplift Saga books has these cultures only build along active plate margins
so that their waste will be destroyed and resorbed by the planet)

> Near water is true, but tide and current has less to do with site
> preference than does a good sheltered harbor, and width of the river
> respectively.   Most towns are built where the river is narrow enough to
> allow a bridge., and rivers change course enough to erode away most
> unattended towns fairly quickly.
>
Well, erode on the outside of the curve and deposit on the inside, of
course.

Good hunting!  Back to the dinosaurs...

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796