Natural selection is the mechanism. It selects for existing traits that are conducive to survival and reproduction because traits which work against survival and reproduction remove themselves from the gene pool (unless, of course, a beneficial gene and a deleterious gene are at closely linked loci, in which case a beneficial trait can carry a deleterious one "along for the ride" if the benefit exceeds the cost of doing so). Surely even creationists believe that much, since it is just as important for microevolution as it is for macroevolution.
Natural selection alone is not responsible for evolution. It only acts on the genetic diversity that already exists and selects for existing traits that make for effective "designs" (if you want to call it that). In order for evolution to really get going, new genetic diversity has to be generated over time. Genetic recombination and mutation are responsible for that part of it (epigenetics probably plays some role as well). If you want me to list some mutations which increase an organisms ability to survive and reproduce, just ask me and I'd be happy to supply them.
I never said they were incompatible. If you believe science has demonstrated an old Earth, then what specific techniques used by science to measure the age of the Earth are you making reference to?
In 1999, evolutionary theorist Jeffrey H. Schwartz wrote that natural selection may be helping species adapt to the changing demands of existence, but it is not creating anything new. As to mutations, I think this quote from The Origin of LifeFive Questions Worth Asking answers the myth of mutations forming new species: "Myth: Mutations provide the raw materials needed to create new species. The teaching of macroevolution is built on the claim that mutationsrandom changes in the genetic code of plants and animalscan produce not only new species but also entirely new families of plants and animals.
The facts. Many characteristics of a plant or an animal are determined by the instructions contained in its genetic code, the blueprints that are wrapped up in the nucleus of each cell. Researchers have discovered that mutations can produce alterations in the descendants of plants and animals. But do mutations really produce entirely new species? What has a century of study in the field of genetic research revealed?
In the late 1930s, scientists enthusiastically embraced a new idea. They already thought that natural selectionthe process in which the organism best suited to its environment is most likely to survive and breedcould produce new species of plants from random mutations. Therefore, they now assumed that artificial, or human-guided, selection of mutations should be able to do the same thing but more efficiently. Euphoria spread among biologists in general and geneticists and breeders in particular, said Wolf-Ekkehard Lönnig, a scientist from the Max Planck Institute for Plant Breeding Research in Germany. Why the euphoria? Lönnig, who has spent some 30 years studying mutation genetics in plants, said: These researchers thought that the time had come to revolutionize the traditional method of breeding plants and animals. They thought that by inducing and selecting favorable mutations, they could produce new and better plants and animals. In fact, some hoped to produce entirely new species.
Scientists in the United States, Asia, and Europe launched well-funded research programs using methods that promised to speed up evolution. After more than 40 years of intensive research, what were the results? In spite of an enormous financial expenditure, says researcher Peter von Sengbusch, the attempt to cultivate increasingly productive varieties by irradiation [to cause mutations], widely proved to be a failure. And Lönnig said: By the 1980s, the hopes and euphoria among scientists had ended in worldwide failure. Mutation breeding as a separate branch of research was abandoned in Western countries. Almost all the mutants . . . died or were weaker than wild varieties.*
Even so, the data now gathered from some 100 years of mutation research in general and 70 years of mutation breeding in particular enable scientists to draw conclusions regarding the ability of mutations to produce new species. After examining the evidence, Lönnig concluded: Mutations cannot transform an original species [of plant or animal] into an entirely new one. This conclusion agrees with all the experiences and results of mutation research of the 20th century taken together as well as with the laws of probability.
So, can mutations cause one species to evolve into a completely new kind of creature? The evidence answers no! Lönnigs research has led him to the conclusion that properly defined species have real boundaries that cannot be abolished or transgressed by accidental mutations.
Consider the implications of the above facts. If highly trained scientists are unable to produce new species by artificially inducing and selecting favorable mutations, is it likely that an unintelligent process would do a better job? If research shows that mutations cannot transform an original species into an entirely new one, then how, exactly, was macroevolution supposed to have taken place?"
