Fossilized remains of Acanthostega, a primitive fish, reveal that even though the animal had rudimentary limbs, it could not walk on land.

棘螈是一种原始鱼类，它的化石遗迹显示，尽管棘螈有基本的四肢，但它却不能在陆地上行走。

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This ability may date back to even more primitive organisms than fish.

动物的识数才能甚至可以出现在比鱼还原始的生物中。

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Many primitive lineages went extinct as sharks and bony fish became masters of the waters and tetrapods, the four-legged animals that eventually evolved into dinosaurs and mammals, conquered the land.

许多原始生物灭绝，鲨鱼和硬骨鱼成为水域的主人，四足动物最终进化成了恐龙和哺乳动物，征服了陆地。

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The primitive fish mouth straining for water and finding it as my son releases it in the shallows.

NEWYORKER: The Other Place