Contrasting the Origin of Species With the Origin of Phyla
FIG E: Phyletic gradualism
Through the continuously gradual transformation of species this model predicts
that the increasing diversity of the lower taxa should precede the disparity
of the higher taxa.
FIG F: Punctuated Equilibrium
Under this model evolutionary change is confined to shorter time spans and
small isolated populations in order to account for the lack of transitional
forms among the lower taxa. Lower taxon-level punctuations, however, require
numerous transitional steps to produce the disparity of the higher taxa.
This model also predicts that the increasing diversity of the lower taxa
should precede the disparity of the higher taxa.
FIG G: The Fossil Evidence: Disparity
precedes diversity.
"We may acknowledge a central and surprising fact of life's history
- marked decrease in disparity followed by an outstanding increase in diversity
within the few surviving designs." -- Stephen Jay Gould, Wonderful
Life, 1989, p. 49
FIG H: The origin of the phyla:
the fossil evidence
Contrary to both Darwinian gradualism and punctuated equilibria theory,
the vast majority of phyla appear abruptly with low species diversity. The
disparity of the higher taxa precedes the diversity of the lower taxa.
FIG J: Darwinian Theory vs. the
Fossil Record
Darwinian theory attempts to explain the common ancestry of all species
through the gradual transformation of major body plans. This theory is in
opposition to the fossil evidence and the pervasive patterns of natural
history.
An estimated 50 to 100 phyla appear explosively at the base of the Cambrian.
Fossil evidence suggesting their common ancestry is not found in Precambrian
rocks. A General Theory of Macrostasis is needed to explain the fossil data
and the stability of the higher taxa.
FIG K: The origin of the phyla:
the fossil evidence
Contrary to both Darwinian gradualism and punctuated equilibria theory,
the vast majority of phyla appear abruptly with low species diversity. The
disparity of the higher taxa precedes the diversity of the lower taxa.
FIG L: The Cambrian Explosion
The sudden appearance of between 50 and 100 disparate body plans with extremely
low species diversity supports the conclusion that neither gradual Darwinian
evolution nor lower taxon-level punctuations can account for the origin
of the higher taxa and the major body plans. In the history of life on earth,
disparity typically precedes diversity.
FIG M: The Present
"We may acknowledge a central and surprising fact of life's history
- marked decrease in disparity followed by an outstanding increase in diversity
within the few surviving designs." (Stephen Jay Gould, 1989)
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