There's no evidence that can't be overturned and exposed as deception in the scientific community. Jehovah's Witnesses don't stonewall any new findings. Popular evidence for evolution in a complex species (maybe someone can present something else). Background on Ring Species: Salamanders:
http://www.pbs.org/wgbh/evolution/library/05/2/l_052_05.html
Ring Species: Salamanders:
Some critics of the theory of evolution argue that it doesn't convincingly explain the origin of new species. They say that members of one species couldn't become so different from other individuals through natural variation that they would become two separate non-interbreeding species.
One of the most powerful counters to that argument is the rare but fascinating phenomenon known as "ring species." This occurs when a single species becomes geographically distributed in a circular pattern over a large area. Immediately adjacent or neighboring populations of the species vary slightly but can interbreed. But at the extremes of the distribution -- the opposite ends of the pattern that link to form a circle -- natural variation has produced so much difference between the populations that they function as though they were two separate, non-interbreeding species.
A well-studied example of a ring species is the salamander Ensatina escholtzii of the Pacific Coast region of the United States. In Southern California, naturalists have found what look like two distinct species scrabbling across the ground. One is marked with strong, dark blotches in a cryptic pattern that camouflages it well. The other is more uniform and brighter, with bright yellow eyes, apparently in mimicry of the deadly poisonous western newt. These two populations coexist in some areas but do not interbreed -- and evidently cannot do so.
By the time the salamanders reached the southernmost part of California, the separation had caused the two groups to evolve enough differences that they had become reproductively isolated. In some areas the two populations coexist, closing the "ring," but do not interbreed. They are as distinct as though they were two separate species. Yet the entire complex of populations belongs to a single taxonomic species, Ensatina escholtzii.
Are ring species excellent evidence for evolution? No. They're not evidence for evolution in the slightest capacity. Vertebrates have degree regarding complexity. Viruses are wildly mutational, however, that is not true of more complex species. The more complex the species, the more static the genome. Things we learn, about the genetic variability of viruses aren't valid for more complex species.
Ring species are best explained by intelligent design using a DNA substitution model.
DNA replication, for biological inheritance, is a process occurring in all living organisms to copy their DNA. This process is "replication" in that each strand of the original double-stranded DNA molecule serves as a template for the reproduction of the complementary strand. Hence, following DNA replication, two identical DNA molecules have been produced from a single double-stranded DNA molecule. Cellular proofreading and error toe-checking mechanisms ensure near perfect fidelity for DNA replication. If DNA replication gets out sync at the reproduction level, it can prevent two species from reproducing.
In phylogenetics, matching DNA sequences is often accomplished by firstly obtaining a nucleotide or protein sequence alignment, and then taking the bases or amino acids at corresponding positions in the alignment as the characters. A, T, C, and G represent a particular nucleotide at a position. Sequences achieved by this might look like AGCGGAGCTTA and GCCGTAGACGC.
Assuming AGCGGAGCTTA is a DNA code necessary for reproduction (the complete substitution model would be much longer). If environmental adaptation has impacted the species at the DNA level and the DNA sequence AGCGGAGCTTA has mutated to ATCGGAACTTA, making the Ensatina escholtzii incapable of interbreeding with its common ancestor at the other end of the ring (genetically unidentical), the mutation for all practical purposes was destructive as macroevolution never progresses beyond this point. It would evidently take an intelligent designer to complete the process.
Basically, we are still looking for an adequate demonstration of evolution in terms of being able to produce some sort of novel complex phenotype structure with function based on changes at the cellular level (genetic or epigenetic) from simpler lifeforms. Any test would have to show that the genetic structure wasn't the result of a minor genetic mutation. There are several challenges of degree regarding complexity.
We have degree regarding adaptation. Creationists expect species to adapt to their environments just as evolutionists do. Are there limits to the degree of adaptation? Is the salamander going to develop new structures based on complex cellular changes so that we will no longer recognize it as a salamander (showing progressive complexity)? Or is this example of a ring species the limit of adaptation and genetic drift? If you answer the questions you will have no empirical evidence.
The theory of common ancestry has to show a mechanism to derive complexity from simpler organisms. Vertebrates are extraordinarily complex at all levels of organization. How did they achieve this? What are the cellular mechanisms?
A whole sequence of mutations would have to be identified and determined along these lines. You can apply any and all scientific methods to this salamander outside its natural habitat and it will still remain a salamander. Species are static and they stay that way.
