"There are plenty of examples of evolutionary change in the history of human life. Bipedalism, cranial capacity, opposable thumbs, Vitamin C dependency, neoteny, dentition, sickle cell anemia, disease resistance and on and on."
From the evidence at hand, one can no more tell that those examples are due to natural selection than one can tell that they are due to Intelligent Intervention. One can look at generations of cars buried in junkyards and claim that the cars self-evolved themsevles rather than were changed by intelligent designers in Detroit and Tokyo, but one would be pretty wrong to claim that those cars self-evolved without intelligent intervention. The same holds true for fossils...
"Computer codes are human inventions and that is all they are so it would be futile to look for one that wasn't."
One could also claim that DNA codes are God's inventions and it would be futile to look for one that wasn't, and that would be just as unscientific.
For science, one must look at all possibilities to see what holds up to repetitive tests. In this case, we can see amazing similarities between human computer codes and human DNA programming, so it makes sense to look at one to see if a theory for the other might apply. Can computer codes form programs without intelligent intervention? If not, then since they are LESS COMPLEX than DNA codes, it's fair to say that DNA can't form without similar intervention.
Are you being purposely ridiculous? I for one have personally witnessed the evolution of the automobile from its very earliest form to the present. I and most of the other folks on this planet know exactly how cars are designed and built. We wouldn't be fooled by a visit to the junkyard.
We also know a great deal about fossils and the geological distribution of fossil species. We know about the geographical distribution of living species. We have thousands of years of records of the results of artificial selection on our domesticated species. We know entire genomes for dozens of species. Etc., Etc., Etc. Data -- Information -- Knowledge -- Understanding -- Wisdom. You need to get your hands on some of the data.
Wrong again. Gene frequencies for sickle cell anemia are maintained in equilibrium in a population as a function of the prevalence of malaria in that population's habitat. Increased infection with malaria leads to an increase in sickle cell trait because heterozygous carriers of the trait are resistant to malaria while homozygous normal folks are not. Being homozygous for sickle cell anemia is fatal. Populations with the trait in regions where malaria has been eliminated experience a decline in the frequency of the responsible gene. This is natural selection.