Grand Canyon cliff collapse reveals footprints made by egg-laying animals 313 MILLION years ago
Grand Canyon cliff collapse reveals clawed footprints made by egg-laying animals that traveled up sand dunes 313 MILLION years ago A boulder fell from a mountain during a collapse at Grand Canyon National Park Experts found there were footprints in the red rock dating back 313 million years The tracks were made by two shelled-egg-laying … Read more