听力文摘：雪橇狗都是什么品种

In books and movies like Call of the Wild, huge, vicious huskies pull sleds for hundreds of miles over the Alaskan tundra¹. A Moment of Science wonders, what kind of dogs are sled dogs?

在书里或者在像《野性的呼唤》之类的电影里，巨型凶猛的哈士奇在阿拉斯加的冻原上可驰骋数百英里。《科学一刻》栏目想知道，到底什么样的狗是雪橇狗呢？

Most champion sled dogs are not pure husky: in fact, the “Alaskan Husky” isn’t really a breed at all: it’s a mix of various breeds. Although not pure bred, every sled dog must be carefully bred for life on the trail.

大多数冠军雪橇狗都不是纯种哈士奇：事实上，所谓的“阿拉斯加哈士奇”根本就不是一个品种，而是由多个品种杂交而成。尽管并非纯种，每条雪橇狗在其拉雪橇的生涯中都需精心喂养。

The dogs need heavy coats to protect them from the cold, and tough feet to prevent injuries. Unlike the tough dogs in the movies, dogs with softer feet wear booties when they run.

狗狗们需穿戴厚重的保暖服以免受寒，以及拥有强健的足部以防止受伤。与电影里面强壮的狗狗不同， 足部柔软的狗狗在奔跑时会穿上短靴。

The dogs also need compact bodies to maximize endurance. The sled dogs’ remarkable² endurance is thanks to their large heart-to-body ratio, and their ability to carry oxygen from the lungs to the muscles, which is about three times that of a human being

狗狗们需要结实的身躯以使自身耐力最大化。雪橇狗耐力持久，主要是因为它们的心脏对比其身体而言相当之大，并且它们将肺部的氧气供给给肌肉的能力是人类的三倍。

On film, large dogs seem powerful, but their size decreases their ability to use oxygen efficiently³. In competitive dog-sledding, dogs usually weigh less than 55 pounds and can comfortably trot⁴ over 70 miles a day.

在电影里，体型巨大的狗狗看起来很强壮，而事实上它们的体型弱化了它们利用氧气的能力。在雪橇狗竞技当中，通常体重在55磅以下的狗狗每天能够轻松地慢跑70英里。

A sled dog also needs the right temperament⁵. They must love running and be sociable⁶ and obedient. Like wild dogs, each team has a hierarchy⁷, but the dogs struggle for position by taking aggressive or submissive postures⁸ such as squealing⁹ and rolling. Real dogfights are rare because the dogs are carefully introduced and trained before going out on the trail.

雪橇狗需性情温和。他们必须热爱奔跑，温顺友好。正如野狗一样，每个狗群都有头狗，但是狗狗们通过极具侵略性的长吠或者表达顺从的滚地等动作来获取位置。狗狗们混战的机率较小，因为在进入雪橇队之前他们就已经受到了良好的引导和训练。

The careful crossing of northern dogs, like Malamutes, with southern breeds like Greyhounds produces dogs with the right stuff to be sled dogs.

北方的爱斯基摩狗与南方品种如长腿猎狗等交配得当，那么他们的后代将具备成为雪橇狗的优良基因。

1 tundra   

n.苔原，冻土地带

参考例句：

• The arctic tundra is at the top of the world around the North Pole.北极冻原是指北极点周边的地区，是世界最高的地方。
• There is a large amount of methane gas under the Siberian tundra.西伯利亚的冻土地带之下有大量的甲烷气体。

2 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

3 efficiently   

adv.高效率地，有能力地

参考例句：

• The worker oils the machine to operate it more efficiently.工人给机器上油以使机器运转更有效。
• Local authorities have to learn to allocate resources efficiently.地方政府必须学会有效地分配资源。

4 trot   

n.疾走，慢跑；n.老太婆；现成译本；(复数）trots:腹泻（与the 连用）；v.小跑，快步走，赶紧

参考例句：

• They passed me at a trot.他们从我身边快步走过。
• The horse broke into a brisk trot.马突然快步小跑起来。

5 temperament   

n.气质，性格，性情

参考例句：

• The analysis of what kind of temperament you possess is vital.分析一下你有什么样的气质是十分重要的。
• Success often depends on temperament.成功常常取决于一个人的性格。

6 sociable   

adj.好交际的，友好的，合群的

参考例句：

• Roger is a very sociable person.罗杰是个非常好交际的人。
• Some children have more sociable personalities than others.有些孩子比其他孩子更善于交际。

7 hierarchy   

n.等级制度；统治集团，领导层

参考例句：

• There is a rigid hierarchy of power in that country.那个国家有一套严密的权力等级制度。
• She's high up in the management hierarchy.她在管理阶层中地位很高。

8 postures   

姿势( posture的名词复数 )； 看法； 态度； 立场

参考例句：

• Modern consciousness has this great need to explode its own postures. 现代意识很有这种摧毁本身姿态的需要。
• They instinctively gathered themselves into more tidy postures. 她们本能地恢复了端庄的姿态。

9 squealing   

v.长声尖叫，用长而尖锐的声音说( squeal的现在分词 )

参考例句：

• Pigs were grunting and squealing in the yard. 猪在院子里哼哼地叫个不停。
• The pigs were squealing. 猪尖叫着。