A Thought on the Definition of Homo Sapiens

I recently noticed that bipedalism seems to consistently be a part of the definition for what a human is, such as in entry 2 of [1] and [2]. I thought this was a bit interesting if one considers those born without the use of their legs, amputees, or how we have to 𝑙𝑒𝑎𝑟𝑛 how to walk. For the first consideration, this suggests that it is possible for one to be a different species from one's parents, but then have your child be the previous species. Disability at birth from bipedal parents is probably due to genetic factors, so upon procreation the child could simply not inherit the non-bipedalism. Thus their parents were humans, they aren't, but their children are. In the second consideration, it suggests that humanhood is something one can lose and regain. This is interesting because the purpose of zoology is to classify species, a genetic thing that isn't supposed to change. Yet amputations and prosthetic limbs makes this supposedly constant classification fluid. For the last thought, consider how we have to learn how to walk (see [3] and [4] for evidence). This implies that we have to learn how to be human, once again contradicting the genetic perspective that taxonomy desires. Perhaps I'm being stupid and bipedalism isn't a part of the definition, but I couldn't seem to find a different definition for homo sapiens or humans.

[1] https://www.merriam-webster.com/dictionary/human
[2] https://en.wikipedia.org/wiki/Human
[3] https://en.wikipedia.org/wiki/Oxana_Malaya
[4] https://en.wikipedia.org/wiki/Feral_child