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And most curiously of all, both have a sixth digit on their forepaws—a kind of ancillarythumb derived from one of the bones of the wrist that helps them hold bamboo stalks for consumption.
最令人驚奇的是，它們的前爪上都長有第六指，是從腕骨長出用來幫助它們在進食時拿住竹莖的輔助拇指。
These common features led Hu Yibo of the Institute of Zoology, in Beijing, and his colleagues, to wonder if the two vegetarian carnivores also shared genetic modifications that might explain those features.
基于這些共同特征，北京動物研究所的胡一波和他的同事們設(shè)想，這兩種食肉目食草動物是否共有一種能解釋這些特征的修飾基因。
And, as Dr Hu observes in a paper just published in the Proceedings of the National Academy of Sciences, they do.
正如胡博士剛剛在《美國國家科學(xué)院院報》發(fā)表的論文中所說的，它們確實共有。
To search for such genetic commonalities, Dr Hu and his colleagues compared the DNA of the two pandas with that of four other members of the Carnivora:
為了找到這樣的遺傳共性，胡博士團隊將兩只熊貓的DNA與另外4種食肉目動物
polar bears (close relatives of giant pandas), ferrets(close relatives of red pandas), and tigers and dogs (close relatives of neither).
（北極熊（大熊貓的近親），白鼬（小熊貓的近親），老虎和狗（非兩者近親））的DNA進行比較。
If pandas share features of their DNA with each other, but not with the four comparison species, he reasoned,
如果熊貓們有相同的DNA特征，而四種對照物種沒有熊貓所共有的DNA特征，
then it is likely that those features encode recent adaptations common to the two of them.
他則推理很有可能這些DNA特征編碼了它們兩者間近代的共同特性。
Altogether, the team identified 70 genes (out of the 20,000 or so that mammals have) which sport bits of DNA that seemed to be shared.
研究小組從哺乳動物約20000個基因中，確定了可以共有的70個DNA片段。
They also found ten genes which have been disabled by crippling mutations in both of the pandas, but not in the other four species.
他們也在兩種熊貓中找到了十個因嚴重突變而喪失功能的基因，而其他四個物種中并未發(fā)現(xiàn)。
Not all of the shared genetic features obviously tied in with the shared peculiaritiesof pandas, but some did.
盡管哺乳動物共有遺傳特征并不都與熊貓的特性一致，但有些確實具有一定的關(guān)系。
These fell into three categories: genes affecting anatomy, genes affecting appetite and genes affecting the digestion and metabolism of nutrients.
這分為三類：影響動物體結(jié)構(gòu)的基因，影響食欲的基因和影響營養(yǎng)物質(zhì)消化和新陳代謝的基因。
英文文本來自經(jīng)濟學(xué)人 譯文來自欄目二第五組
