[VeritatisSplendor]

1) Their parents are cousins. (bad mutation / inbreeding hypothesis)

2) They don't look like habitual use of a four-limbed gait has changed their growth or musculature - paraplegics who wheel themselves have a noticeable change in musculature. (fakery hypothesis)

3) I would guess that chimps with our pelvic structure, glutes, straight legs and spines could walk just fine - that our upright walking owes more to anatomy than a co-ordination gene.

Mrs VS

[gomaaa]

1) Their parents are cousins. (bad mutation / inbreeding hypothesis)

Absolutely the fact that the parents are related is a major factor. Anytime you have a small gene pool, it allows rare genetic mistakes/mutations to come to light. So this is the CAUSE of the wierdness, but the wierdness itself could still be due to old genetic code that is normally inactive. Inbreeding tends to magnify these little mistakes that normally occur but rarely.

2) They don't look like habitual use of a four-limbed gait has changed their growth or musculature - paraplegics who wheel themselves have a noticeable change in musculature. (fakery hypothesis)

It could still be a fake. Still, the article authors say they do have those calouses on their hands from using them in that way all their lives. The pictures I saw don't allow a close inspection of their musculature. I dunno.

3) I would guess that chimps with our pelvic structure, glutes, straight legs and spines could walk just fine - that our upright walking owes more to anatomy than a co-ordination gene.

Yeah, it would probably take many genetic goof-ups to create a human that really resembled a primitive forbear. If it is relevent to our evolutionary history, it only gives us a few clues, not the whole picture.