[MD] Distinguishing Levels (Individual level)

[Heather Perella]

Hey Platt,

     Platt said:  "Inability of a second generation to
breed with a previous one takes evolution nowhere."

     In this statement of yours Platt, you are going
against a main, general, and wide-spread definition
that biologists teach in Biology 100 to accurately
portray according to the current science what it means
for a species to no longer be identified as one
species and must be given a new species label.  A
species changes into another species or is a different
species when the new species can no longer breed with
its' parent population or another population no matter
what they look like - this is defined as evolution. 
Morphology still helps in identification, especially
in the fossil record, but current studies with
animals, even plants, that have similar form are not
always the same species because of this inability to
breed with each other.  That's why there are
evolutionary lineages based on morphology, and other
lineages based on genetics.  These two ways of
defining a lineage rarely ever veer from each other,
they usually come to the same conclusions.

     Platt said:  "Problem is, the fossil record
doesn't show millions of tiny intermediate steps
culminating in a new form. Rather it shows big jumps."

     Yes, that's why Niles Eldridge and the late
Stephen Jay Gould came up with punctuated equilibrium
(PE).  It says evolution occurs with more frequency on
a equilibrium state (static pattern), and then when
change or evolution occurs it will be seen as a
punctuation (dynamic quality at work here) in the
fossil record.  Keep in mind this punctuation still
occurs over a span of a million (if not millions) or
hundreds of thousands of years.  I said PE occurs with
more frequency according to these two scientists,
because where PE occurs in the fossil record,
sometimes though with much less frequency, a slow,
little by little change (I forgot what the term is
called [books of mine still unpacked]) that Darwin
came up with can be noticed in the fossil record.   

     Platt said:  "My theory is that the life force
(DQ) works to change forms for the better. When it
runs up against a catastrophe, like the extinction of
the dinosaurs, it works hard to avoid such
catastrophes in the future.  Thus, it switched from
making bigger and bigger reptiles to creating bigger
and bigger brains, big enough not only to deflect a
meteor like the one that extinguished the dinosaurs,
but to eventually leave this planet and continue life
elsewhere in the universe before the sun expands and
burns out all life here a few billion years from now."

     Your theory is similar to how scientists think
currently.  Even Pirsig's levels have a scientific
mirror in Gould's Hierarchical Theory, which states
pretty much the same thing as Pirsig, but Gould goes
into a lot more detail with scientific data to back up
his theory.  Gould in his book 'The Structure of
Evolutionary Theory' goes into at least a hundred
pages, I believe, on this Hierarchy (which he also
explains does not mean to increasing domination) of
independent levels with for example a biological level
and a social level, etc...  I keep wondering how he or
Pirsig came up with their similar ideas, but again, I
don't have that book with me right now to see any
references Gould might make to Pirsig.  They are so
similar I want to find out.

Thanks,
SA

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