評論
打印
According to my preliminary analysis,
根據我的初步分析
it seems that these animals do not seem to show any differentiation between the dinosaurs from the Northern and Southern Hemisphere
在南北半球的這些恐龍之間，似乎并沒有表現出明顯的區別
and this is the time more or less directly before the final split of the Northern and Southern Hemisphere,
這段時期差不多剛好是在南北半球分裂之前
the final separation of North and South America.
也就是南北美洲分離之時
One continent, one type of meat-eater.
一塊大陸，一種食肉恐龍
It was just as the vicariance theory predicted,
這正是地理分隔理論預測的結果
but then they had to compare dinosaurs for signs of vicariance from after the super-continent split up.
但他們還得比較大陸剛分裂后的恐龍，尋找地理分隔的相關證據
If the theory was right, there should be some differences between dinosaurs from the north and the south,
如果這一說法正確，那么南北恐龍之間必然存在著一些不同點
but because the split had only just happened
但是由于大陸剛分裂不久
these differences would only be slight and very hard to spot
這些差異非常細小，很難被發現
and at first he couldn't find anything significant.
一開始他們沒能找到一點重要線索
In the end he looked again at the radioactive dinosaur.
最后他決定再次研究放射性的恐龍骨骼
Of all the fossils this was the youngest, from well after the super-continent split up.
它是所有化石中最年輕的，來自超大陸剛分裂之時。
Now the interesting thing about this fossil is
這塊化石值得關注的原因是
that this comes from a part of the rock sequence that we actually now believe to be younger than the other fossils that we've seen
我們認為它挖掘出來的巖層比我們找到的其它化石的巖層都要年輕
and with this kind of fossils hopefully then we can answer the question,
有了這類化石，我們就有希望找到問題的答案。
whether the dinosaurs took different evolutionary pathways in the Northern and Southern Hemisphere.
南北半球的恐龍是否真的沿著不同的軌道進化。
