Oceans
The oceans cover 71% of the Earth's surface, contain 90% of the biosphere and hold more biological diversity than the land and freshwater ecosystems.
Only a small percentage of marine life has been assessed. Life began in the oceans approximately 4 billion years ago and it took another 4 million years to appear on land. The planet's biodiversity developed in the ocean and only a few specimens achieved their transition to land, where they began to diversify.
