Bison calves are born in summer and can run within a few hours of their birth.
野牛幼崽在夏季出生，在出生后短短几小时之内就能奔跑cDAi,N2EHI6D[BR)Z。
They have no choice. The herd won't wait in its eternal quest to find new grazing.
它们别无选择)VRgA17lhqeu4。牛群对新草场的无尽追寻可不容等待t1.vj;r^fm+。
Smaller grazers are still found here, too.
这里也存在小型食草动物hq[@c*=5=MuGhC%O。
But they stay put instead of wandering the plains.
但是它们宁愿原地呆着，而不是在草原上游荡，追寻食物_gxmlY*+8nI@&gPf。
Prairie dogs inhabit rambling subterranean towns that stretch tens of square miles.
草原土拨鼠住在蔓延数十平方英里，错综复杂的地下宫殿*9H[[v#-Cw。
These highly social creatures stay within a short dash of their door,
这种社会化程度很高的小东西总呆在他们巢穴大门不远处，
ready to retreat from predators or by weather.
以便在捕食者或者坏天气来袭时，迅速退入巢中MV+KucI]J1_vbMW。
It's always maintenance work to do,
它们对巢穴总是修修补补，
but major renovations have to wait until after rain when the soil is soft.
但大型的整修还待雨后泥土松软时再动工q);((I9lNFyiCk。
All this working and re-working helps the land recover
这些所有的建造和修补都有助于
from the impact of so many bigger feet and appetites.
清除地上大型动物的留下的脚印和食物残渣^7^Kjzc3;*b~mB。
At summer's end, male bison help to move the sun-baked soil as the rutting season starts.
夏末，随着发情期的开始，雄性公牛也开始帮助翻动太阳晒过的泥土#&F]-K(CEF%T%FN。
They roll in dust and paw the ground to try to dominate their rivals.
在与对手竞争中，它们甩动地上大量泥土，
The dust bath also helps to dislodge irritating insects.
这样的泥土浴也有助于消除它们身上恼人的虫子Y|1f&7_;!5!FHGF]VX。
A prairie dog colony is usually surrounded by short, nutritious grass,
通常，草原土拨鼠的聚居地附近，短草肥美，
thanks to the many teeth and toe.
这要感谢那些食草动物勤快的牙齿和脚趾了oX-FUuf=nbf+D|u9^(。
This constant grazing stimulates fresh growth
不停的食草促进新草的生长，
and also keeps the field of vision clear for spotting predators.
还给捕食者提供了清晰了踩点视线#+9BMIio=,TAk0B&s@k。
Larger neighbours are attracted to these burgeoning meadows,
正如一万三千年前那样，
just as they were 13,000 years ago.
它们大块头的动物邻居也被欣欣向荣的田野所吸引am)baK5v@#。