Hand axes would be easy to convey: demonstrate creation and use, repeatedly, and help learners do both. Homo Erectus made hand axes the same way for a million

Hand axes would be easy to convey: demonstrate creation and use, repeatedly, and help learners do both. Homo Erectus made hand axes the same way for a million years, without much innovation, to the point that it's been hypothesised they were more like bird song or bird nests than cultural artefacts. See e.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5066817/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5066817/