But it takes so long to evolve

Mike,A hot topic in evolutionary circles right now is Molecular Clock Theory. It is still a work in progress but it has shown some promise. The Molecular Clock Theory (MCT henceforth) uses the inferred or measured mutation rates seen in organisms and tries to extrapolate back into the fossil record. That is, the rate at which mutations build up in the genome can potentially be used to calculate when two species branched away from their common ancestor. MCT predictions have been corroborated by the fossil record, but the results are still hotly debated. The most difficult hurdle that MCT research has to overcome is agreeing on accurate mutation rates. Differing mutation rates between taxonomic groups also poses a problem. All in all, MCT is an attempt to answer your question in post #1. For the current research, go to http://www.pubmed.com and search for "molecular clock evolution" (without the quotation marks).

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I don't think I do. I am guessing an induced trait = natural selection, or taking a trait available. And random mutations are how the morphological changes happen. I would have to study more to go further as I get confused when we add the mechanism of mutation. I can understand that traits available in the gene pool already can be used = natural selection - I should really be trying to find that topic - and ask over there.

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An analogy I find helpful is a combination lock on a briefcase. Pretend that there are 10 tumblers, each with a 0-9 (like those on a briefcase). Starting with the first tumbler, you randomly choose a number. If you hit the right number for that tumbler, a green light will flash above the tumbler. Proceeding down the line, you do the same at each tumbler, randomly picking numbers and stopping once the light comes on . In this analogy, random mutation is the process of randomly picking the numbers. Natural selection is the flashing green light. While mutations are random, the selection for the "right number", or a beneficial mutation, is not. The "green light" will only come on when the right number is randomly hit. This is why natural selection is often called a process of accretion, since the "right numbers" or beneficial mutations are kept and more are added to them. Without selection, you would have to get all 10 numbers right at the same time. Using the analogy, selection allows you to get the right combination in a maximum of 100 tries (10 tries at 10 tumblers) while a system without selection requires a maximum of 10^10, or 10 million tries.

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"Induced" - never heard of that one till now.

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Parasomnium was trying to show the difference between specific mutations that occur in response to a specific stimulus (induced) and random mutations that are kept in the genome because of their benefice to the organisms. Induced traits are non-random since they occur as a result of a stimulus. And, of course, the induction of traits through this type of mechanism are not observed in nature. Instead, we see a wide array of mutations, some are beneficial and some detrimental, but still independent of the environment.

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I like that analogy Loud, mind if I use it sometime?

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Yeah, sure. I vaguely remember some other analogy using a combination safe, and that's where it stemmed from. I like how the analogy illustrates the step wise nature of evolution, and how selection overcomes the large probability of getting all beneficial mutations in one go (1:100 from 1:10 million). I've been waiting for the right moment to bring this one out. It's amazing how I always get my best ideas during the 45 minutes it takes for me to walk home. Newton has his apple tree, I have the footbridge over the Boise River.

Parasomnium,Thanks for the clarification. It seems that I may have been putting words in your mouth, sorry about that. Mike and I seem to have an affinity for each other at times, so I jumped to help instead of waiting for you to respond. Thanks again.