冷戰(zhàn)期間進(jìn)行的原子彈試驗數(shù)據(jù)幫助科學(xué)家們準(zhǔn)確地測定了世界上最大魚類的年齡。鯨鯊是體型龐大、行動速度緩慢、性情溫和的生物，主要棲息在熱帶水域中。

Stretching up to 60 feet in length and weighing around 20 tonnes, the slow-moving whale shark is very popular with divers. But despite their docile nature, scientists still lack basic information, such as how long the whale sharks actually live.

全身長達(dá)60英尺（約18米）、重約20噸——行動緩慢的鯨鯊在潛水者當(dāng)中很受歡迎。但盡管它們性情溫順，科學(xué)家們?nèi)匀狈τ嘘P(guān)它們的基本信息，比如鯨鯊的真實年齡。

To solve the problem, researchers turned to data from the dozens of atomic bomb tests carried out in the 1950s and 60s. These explosions produced huge amounts of an isotope called Carbon-14.

為了解決這個問題，研究人員參考并利用了20世紀(jì)50年代和60年代進(jìn)行的數(shù)十次原子彈試驗的數(shù)據(jù)。這些爆炸產(chǎn)生了大量被稱作 “碳-14” 的同位素。

As scientists know how long the element takes to decay, they can work out the whale shark’s age, depending on how much Carbon-14 is contained in their bones. One whale shark was 50 years old at time of death. Some can live to be 150.

由于科學(xué)家們知道這種元素衰變需要多長時間，因此他們可以根據(jù)鯨鯊骨骼中碳-14 的含量計算出鯨鯊的年齡。其中一頭鯨鯊在死亡時有50歲。有些可以活到150歲。

詞匯

stretching 長度（可達(dá)）……
weighing 有……重
slow-moving 行動緩慢的
docile 性情溫順、溫和的
turned to 求助于
isotope 同位素
element 元素
decay 衰變

閱讀理解：請在讀完上文后，回答下列問題 。

1. True or false? Whale sharks are fast and fierce creatures.

2. How heavy is a whale shark?

3. To work out how long the whale sharks live, what did researchers turn to?

4. Which parts of the whale shark’s body indicate their age?

答案

1. True or false? Whale sharks are fast and fierce creatures.
False. Whale sharks are slow-moving and docile creatures.

2. How heavy is a whale shark?
A whale shark weighs around 20 tonnes.

3. To work out how long the whale sharks live, what did researchers turn to?
Researchers turned to data from the dozens of atomic bomb tests carried out in the 1950s and 60s.

4. Which parts of the whale shark’s body indicate their age?
Their bones. The amount of Carbon-14 contained in their bones helps scientists figure out their age.