英語聽力：美洲大平原-7

The store of pollen paints a picture of the plains of 13,000 years ago, a picture that looks very different from the open prairie grassland of today.

But why did this region look so different back then? The ice sheets to the north, although retreating 13,000 years ago, still dominated the climate here. It was much milder and wetter than today, ideal conditions for woodland to flourish.

This is how much of the northern plains must have looked when the first people arrived. Not open prairies as it is now, but a parkland of trees and grassy meadows.

This is a relic of those times. The Osage orange. Every autumn it produces these enormous fruits, huge numbers of them, more the size of great fruits than mere oranges.

But there’s no animal alive today that's big enough to pick and eat them, so this bump of crop just rots. The Osage orange glory days are long gone. But its harvest was once an annual feast for many ice age animals, including mammoths. Fruit must have been a real treat for these grass eaters.

1 pollen

n.[植]花粉

參考例句：

Hummingbirds have discovered that nectar and pollen are very nutritious.蜂鳥發(fā)現(xiàn)花蜜和花粉是很有營養(yǎng)的。

He developed an allergy to pollen.他對花粉過敏。

2 grassland

n.牧場，草地，草原

參考例句：

There is a reach of grassland in the distance.遠(yuǎn)處是連綿一片的草原。

The snowstorm swept the vast expanse of grassland.暴風(fēng)雪襲擊了遼闊的草原。

3 grassy

adj.蓋滿草的;長滿草的

參考例句：

They sat and had their lunch on a grassy hillside.他們坐在長滿草的山坡上吃午飯。

Cattle move freely across the grassy plain.牛群自由自在地走過草原。

4 relic

n.神圣的遺物，遺跡，紀(jì)念物

參考例句：

This stone axe is a relic of ancient times.這石斧是古代的遺物。

He found himself thinking of the man as a relic from the past.他把這個(gè)男人看成是過去時(shí)代的人物。

5 mere

adj.純粹的;僅僅，只不過

參考例句：

That is a mere repetition of what you said before.那不過是重復(fù)了你以前講的話。

It's a mere waste of time waiting any longer.再等下去純粹是浪費(fèi)時(shí)間。