Australian scientists are trying to give kangaroo-style stomachs to cattle and sheep in order to cut the greenhouse gases they send out, which is thought to be responsible for global warming.

    Thanks to special bacteria in their stomachs, kangaroo flatulence (肠胃气胀) contains no methane and scientists want to transfer that bacteria to cattle and sheep who produce large quantities of the harmful gas.

    While the usual image of greenhouse gas pollution is a billowing smokestack, pushing out carbon dioxide, farm animals' passing wind contribute a surprisingly high percentage of total emissions in some countries.

    “Fourteen percent of emissions from all sources in Australia are from enteric methane from cattle and sheep,” said Athol Klieve, a senior research scientist with the greensland state government. “And if you look at another country such as New Zealand, which has got a much higher agricultural base, they are actually up around 50 percent,” he said.

    Researchers say the bacteria also make the digestive process much more efficient and could potentially save millions of dollars in feed costs for farmers. But it will take researchers at least three years to isolate the bacteria before they can even start to develop a way of transferring it to cattle and sheep.

    Another group of scientists, meanwhile, have suggested Australians should farm fewer cattle and sheep and just eat more kangaroos. And about 20 percent of health-conscious Australians are believed to eat the national symbol already.

    It's low in fat, it's got high protein levels and it is very clean in the sense that basically it is free-range(放养的) animal,” said Peter Ampt of the University of New South Wales' institute of environmental studies.

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心理学家的防盗门

    杨教授是个心理学家，他刚刚搬进一个大院居住，邻居们就告诉他，这个院子很不安全，经常有小偷来偷东西，所以家家户户都装有防盗门。他们叫杨教授也快点装防盗门。杨教授说：“好，我也装防盗门。”他亲自把木门拆下来，再装上去。

    邻居们看见杨教授鼓捣一番后，门还是原来的门，锁还是原来的锁，就不解地问：“杨教授，你为什么不装防盗门？”

    杨教授说：“我的防盗门已经装好了。”

    邻居们莫名其妙：“你的门明明还是原来那扇木门呀？”

    杨教授说：“是原来的木门，但我已经把它改成防盗门了。”

    没有人相信那扇木门一拆一装就能变成防盗门。大家都说，杨教授可能被知识弄糊涂了。一个人学问钻得太深，往往会连常识都不懂的，例如一些科学家撞电线杆、喝墨水，就是这个道理。邻居们互相叮嘱，以后要多多关照杨教授。

    不久到了元旦，那天搞活动，院子里所有的人都去参加了。搞完活动回来，人们发现家家户户的防盗门都被撬开了，值钱的东西几乎被小偷洗劫一空。

    邻居关心地问杨教授：“你有没有贵重的东西被偷？”

    杨教授说：“我的门小偷打不开。”

    那么多铁门都被小偷打开了，杨教授一扇普普通通的木门小偷会打不开？众人不相信，纷纷来看杨教授的门。

    千真万确，那扇普通的木门依然关得严严实实，小偷把锁撬坏了，锁周围的木板也撬得麻麻花花，可见费了很大功夫，可就是打不开门。

    人们好奇地问：“杨教授，就算是最好的防盗门，撬成这样也早就开了，你这扇木门为什么撬不开呢？”

    杨教授说：“其实，我的门根本就没有锁”他走过去，在不装锁的那边轻轻一扭一推，门就开了。

    众人惊呼：“呀，你的门怎么在这边开的？”

    杨教授说：“对，小偷如果按常规撬门，除非把门连门框一起拆下来，否则是不可能把门打开的。”

    大家恍然大悟说：“原来杨教授跟小偷斗智。”

    杨教授笑一笑说：“我是把防盗门装在小偷的心里。”

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