黃金閱讀 Extinction of the dinosaurs - 英檢

有一句話不知道該怎麼解釋
在第三段
It's hard to understand why they would not be affected, whereas dinosaurs
were left too crippled to cope, especially if, as some scientists believe,
dinosaurs were warm-blooded.

不知道whereas那句到底要放哪邊才是通順的

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