"It is easy, but wrong, to see development in terms of 'genes for X' or a nature/nurture balance."
"Human behaviors are not 'things' more or less influenced by one or
another source. They are processes that are simultaneously embodied and
shaped by experience. The behavior of walking, as just one example,
differs from one individual to the next depending on health history,
body size and shape (for example, limb-to-trunk length ratios), past
physical experience, the character of the walking surface, clothing, and
many other factors."
https://bostonreview.net/wonders/fausto-sterling-motor-development