What I DO doubt is the theory that all land life came from some ocean creature that thought it would find better pickings on dry ground, or that he would be safer from predators if he left the water only to find that the predators too grew legs and followed them .
I'm not surprised that you doubt that because it simply isn't true.
Land life didn't come from any one creature thinking it would do better on land. Land life began because over millions of years some sea creatures (note plural) developed characteristics which gave them the ability to venture further afield and since these characteristics proved to be beneficial, those creatures possessing them tended to be more efficient at surviving and passing those same traits on to their offspring. In every succeeding generation those individuals with a slightly enhanced development of those characteristics, gained a still better chance of surviving and passing them on That's how evolution works. It doesn't think or decide anything - it is simply the process by which those random mutations i.e. longer noses, taller trunks or stronger perfumes, which prove beneficial to those individuals possessing them tend to be passed down and enhanced from generation to generation, whilst those that are detrimental are not.
