re: Evolution: Missing link found. Fish => Tetrapod

No shite?

Although Im sure this is a rough and very general explanation of it, this is what I have learned.

As a species multiplies, random genetic mutation naturally occurs. These are generally very small and usually not noticeable on the macro scale in the organism. A noticeable one may be an offspring being born with a genetic predisposition for slightly larger size, a slightly slower metabolism, or a slight increase in testosterone. In a species with a relatively small population and that still relies on natural selection, this adaption may allow the creature to survive an attack, live longer on less food, or dominate a certain territory respectively. This survival and domination may allow this individual to pass on this gene while others who do not have this gene may have died off because of their lack of it. This fortunate individual gets to reproduce simply by being alive while others are not and therefore passes this gene to his offspring who then may have this gene. They then may have this gene while also having similar physical traits to their parents due to other genes.

Genetic mutations continue to occur similarly to this and either increase the organisms chances of survival and reproduction or decrease it.

This occurs gradually over 100s of millions of years and eventually these small mutations result in massive changes and speciation.

This is generally how evolution occurs.

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Had you gone that fourth semester you would know its "you're".

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it's

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I don't pretend to fully understand but based on college courses in genetics, biology and botany what I remember is this. Genetic mutation is a natural occurrence; it happens often. Most mutations are not helpful and even harmful such as a genetic heart defect. However over millions of years and trillions of mutations rarely a naturally successful mutation coincides with an environmental change that allows said species to survive the change.

The classic and one of the most well documented examples is the English Peppered Moth LINK The misnomer is assigning logic or personification to the process. A species doesn't consciously evolve through it's own strategy, it's just a chance happenstance as a result of the favorable (lucky if you will) mutation that happened at just the right time. Most species, again a classic example was dinosaurs, were not so lucky and died out.

As such, I can imagine that over millions of years with drought conditions over a previously large swampy area/water world that a chance mutation allowed a species previously filtering oxygen from water to become able to breathe air directly. The water breathers died out due to drought conditions and could no longer reproduce obviously so the air breathers became the evolved species because they were able to survive and reproduce. It seems far fetched to be sure from our time perspective but a lot can happen over thousands even millions of years. Just think about the things we have discovered over the last 100 years.

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Logical. Makes Sense.

Are there examples of those mutations happening now? I haven't heard of any. Not saying you're wrong, because what you said makes perfect sense. I was just curious as to why we have all these theories about evolution, mutations (positive as relative to the environment), etc... yet we don't see it in action today. (Reference my baby to adult transformation example).

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Why did the alleles and genes of a particular fish decide it needed the body as a hole to have legs and be able to breath out of water? How did it even know what it needed? Can alleles and genes have intelligent thought to even understand what it needs and why it needs it?

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Of course not - all that genetic information had to be present in the "primogenitor" creature that spawned us all - and it had to be placed there by someone or something, period.

Heck, assuming we were the only animal species on Earth (completely impossible, I know, but for purposes of the discussion) - and all we had were pictures of all the other species, without genetic samples of the material, we couldn't approach cobbling together human genomes to produce the creatures - even if we were given all the necessary equipment by some unseen power.

Yet we're to believe that all these mutations that resulted in an evolutionary advantage, were not fatal and were inheritable (EXTREMELY rare in our admittedly limit scope of observation) changed a single organism into every living thing on Earth.

Even if I accepted that all of that is possible (F*ck it - I'll concede that it is possible), then you have to admit that all that information had to be present at the very beginning - at least in some accessible form - and that information must have come from either some "pre-Earth" donor lifeform or some intelligent creator/initiator.

The law of entropy suggests it did not happen that way - by the way, but at least we have observations of natural selection processes that work counter to entropy, at least as we understand it - albeit on a much smaller scale than proposed.

The duck billed platypus? This guy looks like someone built all other life on this planet from a bucket of animal parts and it was the last few pieces in the bucket. Some guy with a sense of humor was all like, "Yeah, it'll make something."

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Evolution: Missing link found

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mutations that resulted in an evolutionary advantage, were not fatal and were inheritable (EXTREMELY rare in our admittedly limit scope of observation

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The error rate (after repair mechanisms, which wouldn't have evolved until fairly late in the process) in DNA replication is about 1 per 1,000,000 base pairs.

Now multiply that rate by the billions of base pairs in any genetic code. Multiply that by the more billions of replication events (generations) of organisms.

Rare? To the contrary - evolution was, and is, inevitable.

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You're talking about generational alteration of the DNA sequence, which then results in a new species with the "evolved" traits.

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You're right. Scientists have never thought of any of this. You got em!