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

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How the hell do fish "evolve" and "mutate" to where they can go from only breathing underwater to being able to breathe oxygen on land?

It makes no sense.

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Alright, I just did a little research. This is what I came up with:

We all know about natural selection. No need to get into that.

The big differences when species evolve are caused by mutations. Mutations can be beneficial, neutral, or harmful for the organism, but mutations do not "try" to supply what the organism "needs." Meaning, it's not like a fish needs legs to go on land and will eventually sprout legs because he "needs" legs. These things happen through a random mutation.

Some mutations are harmful to a species.

Mutations that occur in non-reproductive cells are NOT passed on to offspring.

Large-scale mutations are those that occur in reproductive cells and can be passed on to offspring.

How do mutations happen? DNA fails to copy accurately. When that happens, weird shite can happen.

**** Now, here is the most important part that is applicable to this article *****



Explaining Major Evolutionary Change


Changes in the genes controlling development can have major effects on the morphology of the adult organism. Because these effects are so significant, scientists suspect that changes in developmental genes have helped bring about large-scale evolutionary transformations.

Developmental changes may help explain, for example, how some hoofed mammals evolved into ocean-dwellers, how water plants invaded the land, and how small, armored invertebrates evolved wings.

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The first ones that came out of the water would basically just slide around on the mud to eat muddy things in the mud. It would then return to the water to breath. Or whatever breathing is called underwater. Over time it could "hold it's breath" longer and longer until eventually it just stopped going back to the water to breath and started hunting with tools.

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No, that would be like saying if you shoot a bow and arrow a lot, you'll adapt to shooting a bow and arrow over generations.

What happens is a mutation occurs or there is genetic trait which makes you mo betta at shooting a bow and arrow. Like really fawking strong shoulders..freakishly strong. Then you kill lots of animals and live and pass on your genes while chicken arms boy dies because he couldn't hold his bow up as long and missed animals. So, his genes die with him.

Take the fish. There is a mutation that allows some air to be processed in the gills (ie...primative lungs) so the mud fish can stay out of water longer, not hold his breath longer. Although, that could be a trait selected for as well. Well, lungfish lives through droughts and gillfish dies. Now you have a primitive lung passed on...and so on.

Need to see over tall grass to avoid the big toothed predator...tall neck horse is going to live while short neck dies. Necks get longer as more of the longer necked ones live and shorter necked ones die.

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What happens is a mutation occurs or there is genetic trait which makes you mo betta at shooting a bow and arrow. Like really fawking strong shoulders..freakishly strong. Then you kill lots of animals and live and pass on your genes while chicken arms boy dies because he couldn't hold his bow up as long and missed animals. So, his genes die with him.

Take the fish. There is a mutation that allows some air to be processed in the gills (ie...primative lungs) so the mud fish can stay out of water longer, not hold his breath longer. Although, that could be a trait selected for as well. Well, lungfish lives through droughts and gillfish dies. Now you have a primitive lung passed on...and so on.

Need to see over tall grass to avoid the big toothed predator...tall neck horse is going to live while short neck dies. Necks get longer as more of the longer necked ones live and shorter necked ones die.

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Yeah, that's pretty much exactly what I said.

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only three semesters of college

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your welcome.

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ISWYDT

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What happens is a mutation occurs or there is genetic trait which makes you mo betta at shooting a bow and arrow. Like really fawking strong shoulders..freakishly strong. Then you kill lots of animals and live and pass on your genes while chicken arms boy dies because he couldn't hold his bow up as long and missed animals. So, his genes die with him.

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You missed the part where Mr. Weakarms is saved by his favorite politician Obama and Mr. Strongarms is forced to give part of his kill to Mr. Weakarms. Mr. Strongarms soon goes gault and the species die off.

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The one all of our biology/genetics teachers like to use is sickle cell. A carrier of sickle cell (passive trait like blue eyes. You have to have bl bl to get blue eyes. bl Br will show brown eyes even though you are recessive b for blue eyes) can survive malaria because of the shape of the blood cell is slightly irregular, while full sickle cell adults die (blood cell too irregular to bond oxygen..IIRC) and full non-sickle cell adults get malaria and die. Sickle cell is passed on. However, white folks don't have it because we were freezing our asses off far away from malaria.

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Yeah, I remember talking about sickle cell in biology when talking about evolution. I remember the pictures of the little half-moon-shaped blood cells.

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You missed the part were Mr. Weakarms is saved by his favorite politician Obama and Mr. Strongarms is forced to give part of his kill to Mr. Weakarms. Mr. Strongarms soon goes gault and the species die off

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Heard a woman call herself a social evolutionist a few weeks ago. Didn't realize they were this committed.

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However, "natural" physical mutations that just suddenly occur based on need, seem much harder to buy in to.

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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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.

Thanks for taking that so well because I truly meant no offense.