In the water, the sideways thrusts of their tails had propelled them forward, but on land, quite different mechanisms were required.
ɪnðə wˈɔːɾɚ, ðə sˈaɪdweɪz θɹˈʌsts ʌv ðɛɹ tˈeɪlz hæd pɹəpˈɛld ðˌɛm fˈɔːɹwɚd, bˌʌt ˌɔn lˈænd, kwˈaɪt dˈɪfɹənt mˈɛkənˌɪzəmz wɜː ɹᵻkwˈaɪɚd.