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Science and Technolgy
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What dinosaurs ate
恐龍吃什么
The belly of the beast
腹中發現
A chance discovery from China suggests some dinosaurs lived in trees
在中國的一次偶然發現暗示著有些恐龍在樹上生活
WHAT dinosaurs ate is, of course, a question as interesting and illuminating as what ate dinosaurs (see article).
恐龍吃什么？當然，這個問題與“什么吃恐龍？”一樣有趣，一樣具有啟發性。
In the case of one particular dinosaur,Microraptor, the matter was addressed in a presentation to the annual meeting of the Society of Vertebrate Palaeontology by Jingmai O'Connor of the Institute of Vertebrate Palaeontology and Palaeoanthropology, in Beijing.
但就“小盜龍吃什么”這一問題（見文章），北京中國科學院古脊椎動物和古人類研究所的Jingmai O'Connor在古脊椎動物學會年會上發表了演說。
Microraptor (see photograph) is one of many small, feathered dinosaurs found in what is now China that were alive during the Cretaceous period more than 66m years ago.
小盜龍（見圖），生活在距今六千六百多萬年前的白堊紀，是現今中國境內發現的眾多體型嬌小、長有羽毛的恐龍之一。
Being feathered, it and its kind were cousins to birds.
這一種恐龍身著羽毛，是鳥類的近親。
The actual split between the two groups, though, had happened much earlier, during the Jurassic period (the first known bird is Archaeopteryx, from 150m years ago), and by the late Cretaceous there were many species of bird around.
盡管，這兩種物種早在侏羅紀時期（已知的最早鳥類是始祖鳥，生活在一億五千萬年前）就已分道揚鑣，而且，到了白堊紀后期，已出現了許多種的鳥類。
What Dr O'Connor and her colleagues have found is the remains of one of those birds, of an as-yet-unidentified species, in the stomach of a specimen of Microraptor.
O'Connor博士和她同事在小盜龍樣本的胃中發現了那時期鳥類的殘骸，但其種類還未得到鑒別。
That is interesting. Discovering direct evidence of what a fossil animal ate, rather than having to infer it from details such as the shape of its teeth, is always valuable.
比起根據其牙齒形狀等細節來推測出結果，找出古生物吃什么的直接證據是有價值的。
But the find's true significance is a small detail of the prey's anatomy: the third toe of its foot.
但是，這個發現真正重要之處卻是其骨骼的一個細微之處：它腳掌的第三個腳趾。那是非常有趣的。
The size of the prey's third toe is important because, among birds, long third toes are helpful for grasping branches and perching in trees.
捕食者第三個腳趾的大小是很重要的，因為，對于鳥來說，長長的第三趾可以幫助其抓緊樹枝，在樹上棲息。
Indeed, the trait is so useful for arboreal life that it is used by many avian palaeontologists to decide whether newly excavated species of fossil birds lived in trees or on the ground.
的確，對于樹棲生物這一特點是相當有用的，而許多鳥類古生物學家也利用這一特點來確定新挖掘出的鳥類化石是棲息在樹上還是生活在地面上。
And the last meal of this particular specimen of Microraptor did, indeed, have a long third toe.
而小盜龍的最后一餐顯然長有長長的第三個腳趾。
That elongated toe suggests to Dr O'Connor that Microraptor, too, was arboreal, and hints that its feathers may have helped it to move through an environment where hops, jumps and flaps between branches were a regular part of its daily activity.
那細長的腳趾暗示著O'Connor博士小盜龍也是樹棲的。在一個需在枝椏間跳躍、滑行的生活環境中，它的羽毛可能對它的日常活動有所幫助。
Whether the first birds evolved from arboreal or terrestrial ancestors is a matter of lively debate among palaeontologists.
關于第一只鳥是從樹棲還是陸生的祖先進化而來，一直是古生物學家激烈爭論的話題。
A fossil formed so long after birds emerged does not, in truth, shed much light on that debate.
事實上，一個在鳥類出現很久之后形成的化石并沒有使得這一論戰明朗化。
But it does suggest feathers may have helped promote life in the trees, even for creatures that could not actually fly.
但是，這的確說明對于居于樹上、即使是那些根本不能飛的樹棲生物來說，羽毛可能真的有助于它們的生活。
