South America was cut off as a giant island for much.of the Tertiary Period, and many animalsevolved there that were found nowhere else. The glyptodonts were big, heavily armoured, armadillo-type creatures that mostly wandered the pampas regions of grassy scrub over the' past few million ye.ars. Theyhad no
teeth at the front of the mouth, and the rear or molar teeth lacked hard enamel covering, but they grew
continuously to replace the wear . from grinding up tough grasses and other plant food. The most recent
glyptodonts survived until a few thousand years ago.