Early dinosaurs underwent vast morphological changes as they aged .

早期的恐龙经历了巨大的形态学变化。

So the dinosaurs lumber on .

所以恐龙只能缓慢前行。

The dinosaurs went out with a bang .

随着一声巨响恐龙灭绝了。

That collision caused the demise of the dinosaurs .

那次撞击导致了恐龙数量减半。

The mesozoic land was dominated by dinosaurs .

中生代时期，恐龙统治着陆地。