Oceans did not exist on earth 4 billion years ago because the surface of earth was too for the presence of liquid water

Yes, oceans did not exist 4 billion years ago because Earth's atmosphere was too hot and it composed of gases that are toxic. It is only later when the Earth started to cool down that water began to surface on Earth and enabled the existence of many life forms that have evolved and became extinct through time.

Answerhave flowing water either episodically or during only a portion of the year;

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