Why did animal life originate in the oceans rather than on the land?

Question

Why did animal life originate in the oceans rather than on the land?

In: 173

Answer 1

There’s a lot of good points in these comments, but there’s one I haven’t seen, so I’ll add that as well:

Liquid is the most effective at letting atoms and molecules meet.
The first step of life being created is self-replication. In the beginning everything was just atoms going around, then molecules going around. But for more complex molecules to be created the odds of those atoms an molecules just colliding by accident is really small. In solids the atoms plainly doesn’t move about enough to collide with other atoms. In gasses there is so much room in between the atoms that they will go long distances before bouncing into another atom. Liquids on the other hand is the perfect combination of atoms and molecules moving around but still being close to each other