英语听力:探索发现 2012-12-12 美洲大平原 American Serengeti—20(在线收听

 This trail leads to the cave and the freshly dead bison, just out of reach.

 
Hunger makes the bear risk everything. He falls and joins the bison in its tomb. Now he can eat his fill.  but after that there's no way out.
 
ln time he'll be just one more ice age specimen. 
 
Outside, another group of predators head for their cave at dusk, pack hunters even more effective than the lion or the wolf.
 
Still relatively new here, they'll eventually transform the ice age plains, and build their own future by exploiting the herds of the American Serengeti. Even the giants that now dominate this ice age world will soon be gone. But they'll leave clues behind, and one day distant generations will pick up their trail and tell their story. 
 
Next week on Wild New World, we discover why mammoths didn't make it through to modern times.
  原文地址:http://www.tingroom.com/lesson/yytltsfx/2012/244998.html