但人们为它们到底填补了哪些进化中的空白仍争论不已——主要是因为人们已有50年未见过一只棘龙的骨骼化石。而已有的骨骼化石早已遗失在二战期间的废墟中了。

Just what evolutionary niche they filled is up for debate - largely because no one has seen a Spinosaurus skeleton for the last 50 years, when it got lost amid the ruins of World War II.

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