If the Earth is more than 70% water, then how come the most intelligent life forms are on land?

@SW-User True, but then whatever life lived in the sea, and still does, is not as intelligent as the higher forms of life on land. So does that mean life may have begun in the water, but it cant progress beyond a certain point in water?

@Dobsdobs life fid indeed begin in water. Evolution depends on stimuli and solutions, successful solutions to that stimuli and time. There's not much weather under the sea, its been pretty consistent in comparison to land. There alot more things going off! Yeah?

@SW-User spell check sucks!

@SW-User What about the various currents, the temperature ranges, the light conditions, pressure conditions? All of these in water provide more natural variables than land. And life has responded. I think I read there are more species in water than on land, which is a response to the more varied conditions in the ocean environment. Yet land has more of the higher intelligent species!!

One reason could be ease of movement on land... if a lot of the body mass has to fight drag in the water then there are less resources left as building blocks of intelligence?

@Dobsdobs this is the time element, the rate of change. The volume of water is enormous, the surface area huge, changes take time, life can proliferate faster, can move to better environments and there is far less of a challenge. Until we showed up and fished the he'll out of it. But it's not over, fish are evolving quickly in our life times to cope with our slaughter. Scientists have concluded that fish are maturing smaller and sooner to evade fishermans nets. How cool is that? The seas won't run out of fish they will just be dramatically smaller! So next time you scrape your half eaten fish dinner into the bin, consider a different source of omega 3 oils.