DaleSpam said:
...evolution is a pretty weak theory. It is not very falsifiable and its predictive power is pretty minimal....
James has already address your "falsifiable" concern, I want to comment on the "predictability" part. It is generally true what you say from an operational POV because in most case, to make a prediction and then experimentally test it takes a very long time for any organism that interests anyone. NSF does not fund experiments with results 20,000 years in the future.
Thus, one must turn to small, short-lived organisms. You may not realize it, but I am sure you have tested and confirmed Darwinian natural selection at least 100 times. - I am referring to your immune system. You have among the 10^11 or so T-cells in your body a few that will fit, but poorly, onto the new antigens of the germs that is making you sick - a totally inadequate defense against their rapidly growing number. Fortunately, the next generation of T-cells (many such every hour) will fit better. Tomorrow, many generations later a significant number will fit the antigens well and their children will have expanded to perhaps 10^8 strong, all by "selection of the fittest" - quite literally the
fitest - This is because those that fit well and bind to the germ antigens have a “changed environment,” which facilities them being
preferentially copied, but not perfectly. The variant in their “children” which fits even better will likewise be “preferentially selected” because, fitting better, more will bind to the antigens and thus be in the environment for increased representation in the next generation, etc. Read up a little on how the immune system
evolves in hours the nearly correct fit T-cells the germ antigen and makes you well again. (AIDs does it evil job by blocking this natural selection process, so you remain with too few defenders.)
I admit that has nothing to do with prediction, so let me drag from memory an old experiment that predicted and then tested. - If memory serves, it took place in South America, perhaps Brazil, but it was years before I moved to Brazil. I must "make up" some of numerical details to explain the prediction, but only the numbers I will use, not the dynamics or results. The experiment ran for about 15 years.
Many small fish living below a water fall were netted and transferred above the falls. Some were more carefully studied tanks with the same water flow thru. The size, 3 inches, and age (2.5 years, by scale rings) at first sexual maturity (developed eggs in females) and life expectancy (6 years when with adults 6 inches) were determined from the tank fish. After the transfer above the falls, predator fish were introduced below the falls, but not above and the years passed. Later fish from both above and below the falls were netted for study in separate tanks. As expected no change above the falls. AS PREDICTED, below the falls the size and age at first sexual maturity below the falls was reduced as was the egg production per fish. When you your chance of being eating is relatively constant, if your genes favor later than average sexual maturity, the percentage of your genes in next generation is decreasing compared to the fish that reproduces at a younger age. In the short period of the experiment, the average onset of sexual maturity was reduced from 2.5 to 1.5 years with the sexual mature fish only 2 instead of 3 inches long and only 2/3 as many eggs per smaller fish.
Fish were chosen with most continuing to live naturally (and cheaply) but one group with a decidedly changed environment (predator fish) which selected out of the gene pool those “foolish” enough to delay sexual maturity, such as had been predicted in the original funding proposal. Fish were also chosen because many fish do adapt their sexual behavior rapidly (some can even convert their sex - a drastic change in less than one generation but this change of course has nothing to do with evolution.)
Many creatures, including man, adjust their sex at birth ratios to provide equal number of both sexes at sexual maturity. (Pre-puberty boys have several percent higher death rates, at least prior to modern medicine, than girls. That is why in all of the world there are more boys than girls conceived*, but the excess is not as great in some Asian countries, where female infanticide has been widely practiced from prehistoric times.) this is more evidence, but not of consciously planed experiment as the “fish experiment” was. The fish experiment was not what however made me believe evolution is true (one confirmation is hardly proof of anything) What convinces me, is I see no way in which it can be avoided. I am confident it applies on all planets to all life forms that encodes and transfer characteristics (imperfectly) to the next generation. If you can conceive of how Darwin’s basic idea could be false for such a life form, I would very much like you to describe it.
I.e. Can you conceive of any such system that would not evolve, at least slowly, if the environment is not static? I think even very conscious effort (careful genetic measurement with quick death to all failing to “measure up”) by very advanced society, might come close, static for thousand of generations, but with such a stable gene pool some “germs” would evolve to seriously threaten it, so, being very advanced, that society would then also consciously change its own gene pool to resist them. Etc. I.e. they would exhibit “selected Darwinian selection” to cope with any serious environmental change. There are few “laws” that seem to be “absolutely true.”. For example I can easily imaging black body radiation might go as T^5, but I can not imagine how Darwin’s basic idea can be false. Some of the details, yes; but not the basic idea for any life form that encodes and hands down the characteristic that make it the life form it is.
---------------------------------------
*With modern sonograms, in some now the boy BIRTHs is significantly higher than in western countries - big problem ahead for some of these boys
