Do you remember the monk and his crinkly peas – Gregor Mendel? Why were his peas crinkly? Or would you say wrinkly? The wrinkly ones were the ones with recessive inheritance, the ones carrying two recessive genes. The peas were wrinkly because they lacked a structural element that would make them normal and smooth-looking.
And then it occurred to me – recessive genes are blanks. Mutation has made them into blanks by loss of function mutations that are errors in the code.
The material of evolution is genetic variation – this is the number of recessive genes in a gene pool that have evolved from wild type genes. I now knew that a modification or so-called new trait could be encoded by blankety blank for that gene locus (a gene locus is the position of a gene on a chromosome).
Biologists say that Natural Selection positively selects advantageous genes, while eliminating genes that would lower fitness. This sort of makes sense, but they have never stopped to reflect on what they actually mean by this, and what their words correspond to in real life.
I had seen the light, and I now knew that ‘advantageous’ is a qualification, not a thing. Biologists think that advantageous mutations establish function, and deleterious mutations cause dysfunction. They think in a good/bad dichotomy. What they have not realized is that both types of mutation have the same basis – both are mutations causing dysfunction at the level of the genome. A switched off gene can be advantageous in a new set of circumstances, and when this is the case, it is positively selected by Natural Selection.