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La paleontología y la evolución:
Tendencias evolutivas
La analogía del borracho
Descendencia
Variación
Herencia
Selección
La historia evolutiva de los foraminíferos
Daniel W. McShea
¿QUÉ ES COMPLEJIDAD?
“La complejidad de un sistema es función del número de
partes distintas que lo integran y de la irregularidad de
su disposición...”
2. Natural Selection + additional factors, such as the environment - this would best be exemplified by Stephen
Jay Gould's and Niles Elderidge's PUNCTUATED EQUILIBRIUM theory, which holds that natural selection only
works in short spurts amongst long relatively stable periods of stasis, lasting hundreds of millions of years, in which
species don't change.
Evidence FOR Intelligent Design: I think even Richard Dawkins would not deny
that complex organisms are designed. (Of course Dawkins would say that it was
NATURE doing the designing, not God - but who is he to say what God can and
cannot do??) To their credit, the Creationists DO try to fully explain the reason why
we see the sudden appearance of complexity, and also they provide a good
explanation for the apparent "directionality" towards complexity.
Evidence AGAINST Intelligent Design: To be honest, it seems most of the time
the "evidence" for intelligent design is more an appeal to ignorance. For example,
Behe will say things like "no one has published a single paper about the evolution of
flagella". Even if this was true, it does not at all necessarily imply (as Behe insists)
that there is evidence of divine intervention (in fact there's been HUNDREDS of
papers published on this subject, but Behe chooses to ignore them!)
1. Natural Selection ("gradualism", or traditional Darwinian
evolution. One of the more recent neo-Darwinists is Richard
Dawkins). Remember, there are THREE MAIN criteria necessary for
evolution to occur via natural selection (see lecture notes from 25Feb-98).
Evidence AGAINST Natural Selection: Even Darwin
himself strongly objected to the idea that Natural
Selection can explain ALL aspects of evolution - in
particular the apparent "directionality" towards
complexity. I personally have a difficult time with
Dawkins' assertion that we are mere vehicles for DNA
to replicate itself - surely there must be more to life than
this!
Evidence FOR Natural Selection: The FACT that
evolution can occur by natural selection is no longer
really questioned by most biologists - but whether
natural selection ALONE can explain the evolution of
complexity is a different issue.
Evidence FOR Punctuated Equilibrium: Again, there are abundant FACTS
within the fossil record that evolution in a manner as proposed by Gould and
Elderidge. Actually, the theory of punctuated equilibrium was first proposed on the
basis of paleontological findings.
Evidence AGAINST Punctuated Equilibrium: As with Dawkin's point of view,
punctuated equilibrium does not fully explain the reason why we see the sudden
appearance of complexity, nor does it explain the apparent "directionality" towards
complexity.