Mammoths, woolly rhinoceroses, and other animals inhabited these vast frozen plains, creating a fascinating world that has now disappeared.....
在人类踏上北美土地之前，巨型生物（massive creatures）统治着这片土地。猛犸象在平原上高耸，剑齿虎在阴影中潜伏。那曾是它们的世界。那么，一切是如何改变的？古生物学家们正一块古老骨头、一块古老骨头.....
