A few weeks ago, evolutionists and myself shared disagreements on the missing definition of species especially among the scientific community. This discussion, once again, highlights the confusion that reigns without any consensus on such a definition.
Strangely, we see the venerable Stephen Jay Gould's banner raised as an epitome of evolutionary defense, however… this is the guy that proposed Punctuated Equilibrium as the most logical substitution to the usual Darwinian examples. As seen here:
"...What do the Finches demonstrate about evolution?
Though the finches were not important in the work of Charles Darwin, they do tell us something about evolution. In particular, over the past few decades, two scientists have done an excellent long term study on the finches on one of the Galapagos Islands. This is accurately described by the textbook Advanced Biology. (Jones, M., and G. Jones. 1997. Cambridge University Press) The authors recount how from 1977 to 1982 there was a drought on one of the Galapagos Islands, and due to natural selection the average finch beak size became larger…
However, this proved not to be the end of the story. If it continued in this way, the average beak size of G. fortis would continue to get larger and larger. But this has not happened (p. 153)
This cumulative change does not occur for two reasons. (1) There are disadvantages to having a large beak, especially when a bird is young. This can outweigh the advantages. (2) The selection pressure on the island fluctuates. In 1982 the drought stopped and there was selection for birds with small beaks.
It can therefore be argued that the study shows natural limits to evolutionary change. Variation in a species is a good thing, as it gives them the ability to cope with environmental change, but variation does have limits.
The Galapagos finches afforded an excellent example of adaptive radiation. It is assumed by evolutionists that a stock of ancestral finches reached the islands from the mainland and then, in the absence of much competition, evolved to fill many of the empty ecological niches occupied on the mainland by species absent from the islands.” (p. 725) Advanced Biology. Roberts, M., M. Reiss, and G. Monger. 2000. Nelson
The Galapagos finches were not as important to Darwin as is often claimed, but they are a good example of micro-evolution. They show us that finches can vary in their morphology, and that natural selection has a role in this.
This study does not give evidence for macro-evolution, and does not prove that natural selection and random mutation could produce the living world as we know it from simple single-celled ancestors.
I especially find it incongruous that Stephen Jay Gould is once again hoist as a paradigm of evolutionary thought, since his writings, most notably his 1981 "Mismeasure of Man" wherein he strongly criticizes typical classroom evolutionary teaching since he saw it as a basis for promoting racisim, were at odds with the usual slow, steady "advancement" of development of species (whatever that may be)...