|MadSci Network: Evolution|
Well, how's that for an open question. On the one hand, the answer depends on your definition of "intelligent". If this definition is purely based on "human intelligence", then that's one thing, but intelligence can be manifested in many forms. Dolphins, for instance, use language, have a social structure and exhibit many qualities that could be deemed intelligent. However, they don't have technology and houses. Anyways, here's my answer. There have been a couple of milestones in the evolution of what we call intelligence. These are the use of tools and the discovery of fire. Clearly, the land animals which had "hands" had a serious advantage when it came to tools. Dolphins may use tools in their own way, but without hands, complex tools cannot be used. Fire is clearly out of the question in a wet environment. It has been said that intelligence came about when the apelike creatures which predated man left the jungles and moved to the plains. At this point they met big beasties like lions and something had to change for their survival. Already quite dextrous, an increase at this level would have been very "difficult" in evolutionary terms, so there were two clear paths for those who would gain an advantage; power and cunning. It happened that cunning prevailed and then it was a fast track towards washing machines and mobile phones. In the sea, it would appear, there is no huge divide in environments. At least there is not a divide like from jungle to plains. Nor, it would seem, is there a huge overcrowding problem, which is what forced the apes out. The sea presents a very large, bland environment which contains no historical reasons for a huge need for an increase in intelligence. Having said that, it does contain a huge diversity of life, which is indicative of co-evolution as opposed to evolution which has strong environmental pressures. It is not always the case that intelligence is the best way to be selected in evolutionary terms. Insects represent a very successful group of creatures which survive very well with only rudimentary intelligence. If you wish to discuss this further, I'm happy to talk over email. The next question, for me at least, is all about conciousness and self awareness. Now there's a wonder.
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