Evolution article: Bacteria make major evolutionary shift in the lab

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NovaProspekt

Junior Member
May 28, 2008
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Originally posted by: BladeVenom
630,000 years for a single gene. What would it take to go from apes to humans at that rate? Trillions of years? Quintillions?

How much more complex do you think a human is than an ape? How much more complex than a bacteria?

There are quantitative estimates to these questions and I suspect the answers would surprise you.
 

fskimospy

Elite Member
Mar 10, 2006
83,716
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Originally posted by: Craig234

Thank you for the comments, but I don't think they begin to address the issue of the lengthy, complex evolution to wings.

And if it were that simple, you might think other animals would have grown wings, too, but no cats or dogs have them (though Dr. Pink Floyd did discover some pigs with them).

I understand simple mutations which are useful, like the flagellum as motor. A wing "hey, this lightweight limb with something called feathers flies, what a surprise" is another thing.

Then again you might think turtles would have something to better turn themselves upright.

There's a lot of mystery to me in it.

But that's sort of the point of the video, the flagellum was not a simple mutation. There were dozens of steps on the way to a flagellum becoming a motor and almost none of them actually had to do with locomotive function. Each step along the way conferred a different advantage in it's own way.

It's sort of the question of 'what good is half an eye?' and the answer is: a lot of good.
 
Oct 27, 2007
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Craig, your questions would be answered if you bothered to read even a single well-regarded popularized evolution book.

As for the OP, great article but it's not like we need any more evidence for evolution. The theory is rock solid and not disputed by anyone with a modicum of knowledge on the subject. Those who oppose the theory on idealogical grounds will never accept it, no matter how much evidence they see.
 

Craig234

Lifer
May 1, 2006
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Originally posted by: eskimospy
Originally posted by: Craig234
Post withheld:)

Too late, I have immortalized it in quotes!

Remove my post, dammit.:) Thanks for the video, that's partly why I removed it, as I saw the video and realized I needed to update the comment.
 

Craig234

Lifer
May 1, 2006
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Originally posted by: GodlessAstronomer
Craig, your questions would be answered if you bothered to read even a single well-regarded popularized evolution book.

Thanks for the jerky condescending tone in response to my candid admission.

You think you are being helpful? I didn't say "these are mysteries to biologists".
 

nonameo

Diamond Member
Mar 13, 2006
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Originally posted by: Craig234
It's very interesting. As someone who believes in evolution, I've always had some basic questions about it - a lack of understanding how complex things develop. For example, winged creatures - assuming that wings gradually develop, *why* do they go through all those complete useless phases leading up to where they actually allow flight? It's not as if wing-stubs help survivability.

I'm not talking about where the interim phases are useful, but ones where there's a gap between the 'before' and the later useful development that's large and boggling to think of as random mutation, especially with a long, complicated development. It's not as if the first little wing stubs know they're going to lead to flight.

That's because evolution is not about anything at all. It's just a bastard love child. (no offense to bastard love children.)
 

mxyzptlk

Golden Member
Apr 18, 2008
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Originally posted by: eskimospy
Originally posted by: Craig234

Thank you for the comments, but I don't think they begin to address the issue of the lengthy, complex evolution to wings.

And if it were that simple, you might think other animals would have grown wings, too, but no cats or dogs have them (though Dr. Pink Floyd did discover some pigs with them).

I understand simple mutations which are useful, like the flagellum as motor. A wing "hey, this lightweight limb with something called feathers flies, what a surprise" is another thing.

Then again you might think turtles would have something to better turn themselves upright.

There's a lot of mystery to me in it.

But that's sort of the point of the video, the flagellum was not a simple mutation. There were dozens of steps on the way to a flagellum becoming a motor and almost none of them actually had to do with locomotive function. Each step along the way conferred a different advantage in it's own way.

It's sort of the question of 'what good is half an eye?' and the answer is: a lot of good.

You can look at the life cycle of an existing bird and watch it go through the evolutionary steps toward flight.

At a young age, too young to fly, birds will scamper around, flapping their proto-wings for stability and minor propulsion. They can scramble up inclines too steep for them to walk by flapping their wings and as they grow bigger, they start making short hops which gradually extend to full powered flight.
 

mxyzptlk

Golden Member
Apr 18, 2008
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Originally posted by: nonameo

That's because evolution is not about anything at all.

Right.. it's not a goal or a purpose. It's more of a description of things that have already happened. You can't say something is evolving towards a goal, only that it has evolved from something that came before it.

 

Craig234

Lifer
May 1, 2006
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Originally posted by: mxyzptlk
Originally posted by: eskimospy

But that's sort of the point of the video, the flagellum was not a simple mutation. There were dozens of steps on the way to a flagellum becoming a motor and almost none of them actually had to do with locomotive function. Each step along the way conferred a different advantage in it's own way.

It's sort of the question of 'what good is half an eye?' and the answer is: a lot of good.

You can look at the life cycle of an existing bird and watch it go through the evolutionary steps toward flight.

At a young age, too young to fly, birds will scamper around, flapping their proto-wings for stability and minor propulsion. They can scramble up inclines too steep for them to walk by flapping their wings and as they grow bigger, they start making short hops which gradually extend to full powered flight.

Well, that's an entirely different meaning/type of 'evolution', one that's programmed into the bird already. Just as human babies are helpless, but grow into dangerous creatures.

It's the evolution of the complex functions which have many interim steps that *seem* useless or even counterproductive that I'm discussing.
 

mxyzptlk

Golden Member
Apr 18, 2008
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*shrug* I thought I was answering your specific question about wings and intermediary steps towards flight.

There probably are lots of little bits of random mutation that are useless and/or counter productive. Over time (lots and lots of time) the useless shit gets filtered out and the useful stuff doesn't (I can tell that you already know all this)
 

CottonRabbit

Golden Member
Apr 28, 2005
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Originally posted by: eskimospy
Originally posted by: lupi
Originally posted by: CottonRabbit
It's funny that the actual experiment and publication was meant to address a completely different issue than what is being discussed here and in the news article. This wasn't something done to "prove" macroevolution.

Welcome to the AT forums where anything Bush, Clinton, or religion related is a fair beating subject.

What are you talking about? As I understood his post he just thought it was funny that the experiment provided a huge chunk of evidence in favor of evolution without even meaning to.

It doesn't matter if the experiment was set out to 'prove' evolution, what actually happened is what matters... and this is big big news.

Actually, I really meant that it's funny that an experiment with a goal of examining the effect of historical contingency on evolution becomes dragged into the debate about whether evolution is true or not. It would be like if an astronomer makes the first direct observation of a black hole only to have the public debate about whether the black hole proves gravity.

Basically, no matter how much creationists whine, biologists will still be using the theory of evolution as a foundation to make tremendous discoveries.
 

Craig234

Lifer
May 1, 2006
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Originally posted by: mxyzptlk
*shrug* I thought I was answering your specific question about wings and intermediary steps towards flight.

There probably are lots of little bits of random mutation that are useless and/or counter productive. Over time (lots and lots of time) the useless shit gets filtered out and the useful stuff doesn't (I can tell that you already know all this)

Oh, surely there are lots of useless things that aren't propagated. (Like Republican orientation should be weeded out soon:) )

I think you were making an analogy between young birds having some use for pre-flying wings helping them get up steep inclines, and birds earlier in the evolutionary cycle doing the same, as evidence of usefulness for the incremental stages of wing development. It's an interesting hypothesis, but I'm unsure how useful they'd be, and the difference between what's useful in those earle stages, and the complex design in material and form needed for the huge jump to flight, is still not clear to me.

You did raise an interesting comparison though between the evolution of the species and the development of the bird after conception, I had not considered them together.:)
 

CottonRabbit

Golden Member
Apr 28, 2005
1,026
0
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Originally posted by: Craig234
Originally posted by: mxyzptlk
Originally posted by: eskimospy

But that's sort of the point of the video, the flagellum was not a simple mutation. There were dozens of steps on the way to a flagellum becoming a motor and almost none of them actually had to do with locomotive function. Each step along the way conferred a different advantage in it's own way.

It's sort of the question of 'what good is half an eye?' and the answer is: a lot of good.

You can look at the life cycle of an existing bird and watch it go through the evolutionary steps toward flight.

At a young age, too young to fly, birds will scamper around, flapping their proto-wings for stability and minor propulsion. They can scramble up inclines too steep for them to walk by flapping their wings and as they grow bigger, they start making short hops which gradually extend to full powered flight.

Well, that's an entirely different meaning/type of 'evolution', one that's programmed into the bird already. Just as human babies are helpless, but grow into dangerous creatures.

It's the evolution of the complex functions which have many interim steps that *seem* useless or even counterproductive that I'm discussing.

Well in the case of bird flight: feathers probably first developed on dinosaurs as insulation or as mating displays, then some small dinosaur with feathers became tree dwelling, then these feathers may have turned out to be good at letting them move more efficiently between trees by gliding, then natural selection began selecting for lighter and more aerodynamic dinosaurs that could glide better, and after millions of years, these dinosaurs/birds begin to actually be able to fly.

Of course there are other hypotheses on how this happened, but all probably center around how existing features in a dinosaur population became selected to fit a new adaptive behavior and slowly this behavior became flying. The previous gliding/jumping, while not as efficient as flying, did confer some sort of fitness advantage to the population.

Also, the experiment described in this thread kind of addresses your concerns. In this case e-coli made its huge change actually in 3 steps. The first 2 steps were relatively neutral, and would seem useless if evolution stopped then. But this population still kept this variation because it wasn't harmful enough to be selected against.
 

Craig234

Lifer
May 1, 2006
38,548
348
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Originally posted by: CottonRabbit

Well in the case of bird flight: feathers probably first developed on dinosaurs as insulation or as mating displays, then some small dinosaur with feathers became tree dwelling, then these feathers may have turned out to be good at letting them move more efficiently between trees by gliding, then natural selection began selecting for lighter and more aerodynamic dinosaurs that could glide better, and after millions of years, these dinosaurs/birds begin to actually be able to fly.

Of course there are other hypotheses on how this happened, but all probably center around how existing features in a dinosaur population became selected to fit a new adaptive behavior and slowly this behavior became flying. The previous gliding/jumping, while not as efficient as flying, did confer some sort of fitness advantage to the population.

Also, the experiment described in this thread kind of addresses your concerns. In this case e-coli made its huge change actually in 3 steps. The first 2 steps were relatively neutral, and would seem useless if evolution stopped then. But this population still kept this variation because it wasn't harmful enough to be selected against.

Your post raises new questions, though, for example if feathers could become such a randomly developing and persistent feature, why we don't see more oddness in, say, humans with 6 or 7 fingers, which also seems 'harmless enough not to be weeded out'. Sure, we do occasionally have a mutation there, but nothing like the sort of regular feature that might turn into more like feathers in above.

Anyway, I'd like to note another analogy with evolution, how some artistic areas seem to have analogous issues of evolution. Those of us who have played computer games for a while know how the 'art form' has evolved, with new paradigms providing incremental improvement to the earlier ones, how at first merely interacting with text, or moving graphics on the screen, were amusing, leading through a lot of phases; you could not see World of Warcraft, regardless of hardware technology, developed early in gaming.

It applies to other areas, too, like rock music; and we particularly note when someone makes one of those 'jumps' in evolution, notably in rock for example when the Beatles released the Sgt. Pepper album in an era of light pop, and many people saw the rock music art differently after (with psychedelics helping the mutation:) ).

Similarly, in movies, a genre like 'film noir' was invented by experimentation in one film.

Similarly, after centuries of straightforward oil painting, the surrealists mutated.