I do not have access to arctic charr. They are very intersting though. There is a lake in Iceland that holds four different morphs from a single ancestor. Google lake Thingvallavatn and you can read all about them.
Thanks for the tip. That has led to some very interesting reading about Iceland, which I will pursue further. There is apparently some fascinating history associated with that place, as well as geology and ecology.
I agree that what i discribed about stickleback is a loss of characters, but would disagree that it is a loss of genetic information. The genetic information has not been lost but has changed and caused a phenotypic loss. This is evolution. If you do not think that character loss is evolution then you should ask a naked mole rat or a blind cave fish. These losses are adaptive. Evolution does not need to be progressive or have a destination.
That is like saying that an albino has had his pigment information change. His pigment information has not changed, it has been lost. He cannot make pigment. Period. He never will make pigment. It did not change to a different color pigment; it is the absence of pigment. The blind cave fish did not have his eyes change to a different kind of eye, he simply has no eyes. He has lost the genetic information necessary to make eyes. The naked mole rat did not have his hair changed, he cannot grow hair. He has lost the genetic information necessary to grow hair. I have lost some hair too. I must be evolving
As far as adding "genetic information" (which I'm not sure exactly how we are defining this), There is a growing amount of evidence that there have been numerous rounds of genome duplication throughout metazoans history. The latest being in teleost. I think that this would qualify as addition of genetic information.
I'm sure Teleost will be glad to hear this. Anyway, what does "duplication" mean? It means copying. It does not mean the creation of anything new. Show me, for example, where the genetic information to make an eye came about, when it was not there before. And tell me who was there to observe it and document it. An eyeless animal never laid an egg to have an animal with an eye hatch. No one ever observed it, and no one ever will. To believe that this ever happened is pure speculation, making the interpretation of fossils etc. fit the world view of the interpreter. You may choose to believe that birds are descended from dinosaurs, but nobody ever observed a dinosaur lay an egg and a bird hatch out. And nobody ever will.
I agree that things change over time. Wolves, due to isolation caused by a combination of geography and the will of human breeders, have become hundreds (maybe thousands) of very diverse breeds of dogs. This was done by selecting certain traits to be passed on and others not to be passed on. Genetic information was lost to make this happen. And yet they are all still dogs, and can interbreed. If feral dogs of different breeds hybridize, their genetic information will recombine and their descendants will revert to wild dogs.
When inbred fancy goldfish are released into streams and lakes, they interbreed and are known to revert through successive generations to their wild state.
There has been extensive talk on this forum about hybridization in sunfish. They can hybridize because they are essentially the same kind of fish. Different isolated breeding populations of the ancestral sunfish lost different genetic information, making the various kinds we see today. When they hybridize, they mix genetic information, restoring some of the diversity of genetic information and making them closer to the ancestral sunfish. It might be interesting to breed them all together to see what results.
Well, I better come down off the soapbox now. There are too many other new topics to read. I'll catch up with you later.