Posted by Coach on May 12, 1998 at 13:21:17:
In Reply to: The Beak of the Finch posted by Carlos on April 23, 1998 at 11:23:51:
: "The Beak of the Finch" by Jonathan Weiner (which I acquired and read because of the review on rpcman’s site) is largely an account of the work of Peter and Rosemary Grant, who have been studying finches in the Galapagos Islands since 1973. Darwin studied these finches during his travels, and wrote about them in "Origin of the Species".
: The finch population of the Galapagos is perfect for a study of evolution in action because of the limited number of species and the closed nature of the ecosystem (since the one island where they focused most of their study is quite isolated).
: The Grants have studied over 20 generations of finches, many thousands of individual birds. They caught virtually every bird, measured them and kept track of their progeny. The result is an empirical account of evolution in action. The inescapable conclusions from their work include: (1) evolution by natural selection does occur; (2) natural selection can occur at a much faster pace than most people realize; (3) we have a much better understanding of how speciation (the creation of new species) can occur (although the Grants did not observe this directly).
: Weiner also discusses efforts by others to document evolution occurring in fish populations, where speciation was actually observed.
: The last part of the book discusses evolution by natural selection among bacteria and viruses. Anyone who follows the news is aware of the emergence of resistant strains of bacteria. Many don’t understand how they become resistant - through natural selection. A given antibiotic may kill 99% of a bacteria, but because of mutations and subtle differences among the bacteria some will survive. Also, bacteria under stress (under attack by antibiotics) literally open their cell walls to envelope plasmids (strands of DNA) from other bacteria or even viruses in an attempt to survive. Sometimes those attempts are successful, and resistant strains of bacteria are born. Those strains become dominant and spread through society, and soon we can’t kill bacterial infections with certain antibiotics anymore. The same example can be made with insects and pesticides.
: We frequently hear arguments from people who don’t "believe" in evolution. That is utter nonsense. The theory of evolution has been as rigorously proven as any scientific theory. Whether you believe in it or not, it is happening right now all around you.
In fact, you are speaking of two different things. The study of the differences in the beaks of the Galapagos finches is a well documented case of Natural Selection favoring a characteristic that was ALLREADY IN THE GENE POOL. All of the finches of the Galapagos Islands are still, however, finches. And they are very similar to the mainland finches which probably gave rise to their populations. On the other hand, there is no evidence in the Galapagos or anywhere else that I know of that Natural Selection is in any way capable of producing individuals which are of different species from individuals of the same species. In fact, Stephen Gould, arguably the worlds leading Authority on evolution has publicly stated that Natural Selection is not a good or sufficient means for speciation. His latest hypothesis is the Punctuated Equilibrium Hypothesis which postulates that
life on Earth remains essentially unchanged for long periods and then a natural disaster (alla Deep Impact) wipes 90% or more out and a combination of Natural Selection, inbreeding, and mutation make for rapid changes. So rapid, in fact, that there is little or no fossil evidence of intermediate forms. Gould and friends felt obligated to come up with a new theory because as good scientists they could not get around the lack of intermediate forms in the fossil record and the damage it did to the theory. So your assumption that Evolution has been "rigoruosly tested" is in fact wrong. Not only from a "none of the leading people in the field can agree" point of view, but also from the "it is impossible to test a theory that takes billions of years and non-existing conditions to occur.
In fact, because Science cannot 'recreate' evolution, the Theory of Evolution( and all sub-theories) will never have the same level of objective data as say the Theory of Relativity, which can be objectively tested with many different techniques in the lab. So it is fair to say that Evolution (Speciation, not Adaptation) is to some degree a matter of Faith. It is especially subject to criticism by Mathmaticians and Physicists, because there is no mechanism that adequately explains how a random process that should take more years than there have been seconds in the Universe could have occured in so short a time.