Their vertebral columns, limbs, limb girdles and musculature needed to be strong enough to raise them off the ground for locomotion and feeding.
ðɛɹ vˈɜːɾɪbɹəl kˈɑːlʌmz, lˈɪmz, lˈɪm ɡˈɜːdəlz ænd mˈʌskjʊlətʃɚ nˈiːdᵻd təbi stɹˈɔŋ ɪnˈʌf tə ɹˈeɪz ðˌɛm ˈɔf ðə ɡɹˈaʊnd fɔːɹ lˌoʊkəmˈoʊʃən ænd fˈiːdɪŋ.