These are the skills that are transferred through writing. Later schooling uses books extensively but not exclusively. Mathematics depends almost completely on writing. Some skills may be learned from books and then used independently, while other skills will always use written material, i.e. reading and/or writing during the execution of the skilled behaviour.
Skills group into professions and trades, each of which have its own vocabulary and language-use, and its own history of evolution of the corresponding skill-set.
Parts of the mechanism for evolution:
Skills: to model as illustration
Prerequisites for the mechanisms and processes of evolution:
Reading & writing-based functions required for subsequent skills: