英语听力:自然百科 黄石公园的夏天 Yellowstone—16(在线收听

 Bison calves are more independent of their mothers. The adults' focus is now set on a ruthless competition to mate. A male bids to enter a herd with females in season. He uses dust to accentuate all his size and power.

 
Another male already established in the herd, answers the display, and waits. 
 
The newcomer responds by scent marking and moving even closer.
 
This challenge can not be tolerated.  
 
The resident male has won. Having seen off his rival, next summer's calves will likely be his-------victory in the dust of high summer. But now there's a larger challenge to the whole of Yellowstone. These clouds don't signal rain.
  原文地址:http://www.tingroom.com/lesson/zrbaike/2012/273757.html