必克VOA新闻：蜜蜂化石揭示气候变化

Fossilized Bees Reveal Climate Changes

Fossils from California’s La Brea Tar Pits keep supplying scientists with excellent material for studying the region’s past. Ancient animals, from mammoths to tiny insects, reveal facts about climate changes during the last Ice Age and help scientists understand the modern climate.

For millennia, natural tar that seeped from the ground in what is now southern California trapped large and small animals, preserving their fossils and providing scientists with a trove of specimens suitable for study.

Anna Holden, a researcher at the Page Museum in Los Angeles, is analyzing fossilized bees to learn about the ancient environment of the tar pits. In trying to reconstruct what the climate and local habitat were like, she said, “this bee offered kind of unprecedented information."

By exposing the fossils to a micro CT scanner, scientists discovered that the bee’s habitat was warmer than expected. They concluded that at the end of the Ice Age, about 11,500 years ago, this area was not covered with snow and ice, as previously thought.

Insects’ limited range – unlike that of the large mammals that came to La Brea from South America or across the land bridge now covered by the Bering Strait – allows the collection of detailed information about their immediate environment, Holden said.

“Insects have very specific life cycles, so they're just really good paleoecological indicators,” she said. “In other words, they're just very specific in their behavior, their habitats.”

Whoever collected the specimens in the 1970s did a good job of keeping records, Holden said. Comparing that data with current findings can reveal something about our future.

“Understanding past climate change is understanding current climate change,” she said. “Climate change is a big issue right now and insects are often really good indicators.”

Holden said her work may help today’s farmers fight the problem of collapsing bee populations, by switching over to bee species better adapted for the changing climate.

词汇解析

reveal

难度：4星核心词汇，属常用3000词

英汉解释

vt.显示；透露；揭示；展现

n.(外墙与门或窗之间的)窗侧；门侧；(汽车的)窗框

参考例句

用作及物动词 (vt.)

Several withered trees on the sides of the road reveal the desolation here.

道路两旁的几棵枯木显示出这里的荒凉。

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researcher

英汉解释

n.研究人员

参考例句

用作名词 (n.)

Researcher redefines the physics of photons.

研究人员重新定义光子物理学。

Vendors would give public credit to the researcher.

销售商则将给予研究人员公开好评。

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respond

难度：4星核心词汇，属常用3000词

英汉解释

v.回答；响应；反应；反应灵敏；反响

n.[建]壁联；[宗]应唱圣歌

参考例句

用作动词 (v.)

I invited her to dinner but she did not respond.

我请她吃晚饭，但她未作回答。

The professor lectured with a beaming countenance, but the students didn't respond much, only agreeing with what he said.

教授讲得眉飞色舞，学生们却没有太大的反响，只是随声应和。

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limited

难度：5星基本词汇，属常用1000词

英汉解释

adj.有限的；被限制的

动词limit的过去式和过去分词形式.

参考例句

用作形容词 (adj.)

We had only limited communion with the natives.

我们与本地人的交往有限。

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collection

难度：4星核心词汇，属常用3000词

英汉解释

n.收集；收取，托收；聚集；收藏品；募捐

参考例句

用作名词 (n.)

The collection of these stamps took ten years.

收集这些邮票花了十年时间。

The firm contributed 10,000 to the collection.

公司拿出10,000元做为募捐。

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immediate

难度：3星常用词汇，属常用6000词

英汉解释

adj.直接的；最接近的；立即的；目前的

参考例句

用作形容词 (adj.)

The evidence has no immediate bearing on the case.

该证据与本案无直接关系。

Today's immediate problem is one of distribution of both food and income.

目前面临的紧迫问题是食物分配和收入分配问题。

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fleet

难度：4星核心词汇，属常用3000词

英汉解释

n.舰队；船队；机群

adj.快速的；敏捷的；短暂的

vt.使（时间）飞逝

vi.疾飞；掠过；逐渐消失

参考例句

用作名词 (n.)

The general ordered the fleet to remain where they were and wait for the further instructions.

将军命令舰队原地待命。

用作形容词 (adj.)

That is a fleet horse.

那是一匹快马。

用作及物动词 (vt.)

On board the ship I fleet time by read detective story.

在船上我读侦探小说，借以消磨时间。

用作不及物动词 (vi.)

A plane fleeted over the top of the hill.

一架飞机掠过山顶。

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current

难度：5星基本词汇，属常用1000词

英汉解释

n.趋势；(水、气、电)流

adj.现在的；流通的

参考例句

用作名词 (n.)

Nothing disturbs the peaceful current of life in the village.

没有任何事干扰村里一向平静的生活.

用作形容词 (adj.)

How long will she keep her current job?

她现在这份工作能维持多久?

 

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