still mark the American landscape today... 如今仍在美国的地貌上显现
allowing the giants of today to evolve. 使如今的巨兽得以进化
Today, they are 2,500 kilometers long, 如今该山脉长2500公里
And it's still just as important today. 这在今天依然非常重要
...evolving into the 18 different species we know today. 进化成 我们今天所知的18个不同的物种
And their descendants are still at it today. 它们的后代 至今任保持着这样的行为方式