nostr:npub1khx67x36rsu5y2f3ruuq8crnxndmep88399l2phu50etnfcrkr6q6hgeyg I saw SJ Gould make this point in a talk once, and he had a great parody image -- wish I could find it -- in which after achieving upright posture the creatures, inevitably, begin to lean backwards, ultimately crawling belly-up.