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Good answer. You do make a strong case for our close relationship to chimps.
Good answer. You do make a strong case for our close relationship to chimps.
Good answer. You do make a strong case for our close relationship to chimps.
I think he has said he was an insurance salesman before.
We'll probably know better when we can definitely answer "how" it evolves. Evolution is the closest we have, and so far as withstood every challenge.
People used to ask "why does the moon move"? Once we figured out how does it move, that question was answered too.
Yes, we have a Newtonian model to explain our observation of celestial mechanics, but it doesn't explain why such mechanics exist.
I can agree that statistically speaking, there's probably long odds it can happen in one generation. Obviously, the smaller the genome, the biggest the odds, even if they're still pretty long.
But don't forget that you're also talking about only one specific event (the development of the Cit+ phenotype). The thing is, there's all sorts of other events that take place on almost every generation, that might not be as notable as that but are just as important (ie: interacting better with other E.Coli, etc).
I don't see it like that at all. If you want to say there's certain aspects of evolution that have not been verified yet, that's fine and I agree. That's why it's still a theory and being actively researched. Research that's done not just to verify, but to potentially falsify said aspects of the theory too.
Now, when you try to discredit said research by imposing some bar that's currently unattainable and not even the researchers are imposing, AND, on top of that your alternative is some unverifiable claim that we're supposed to accept without any evidence bar whatsoever, I think you're just deluding yourself.
True.
Sure, probably the most notable change so far.
What do you mean 'rebooted'? The only thing they do every 75 days (500 generations) is take a mixed-population sample and store it in a freezer so at any given point in time they can both calculate the mean fitness relative to the ancestor and could also be used to re-start the cultures at that point in time if desired in order to conduct specific experiments with the population at that time. It's basically a freeze-frame of the evolution process at that point.
The actual populations used as base keep evolving, and AFAIK, were never 'rebooted' back to the ancestor.
Because it's genome is relatively small at 4.6 million. According to Lenski, there were about 22 billion mutations observed in all populations at the 30,000 generation mark. That's good enough to determine that at least every base pair has mutated from the ancestor at least once. However, it's a drop in the bucket when looking at different combinations that might be present at a given generational change. Not to mention that with each generation, new selection is applied based on factors such as environment, current mutation state, etc. and also that RNA evolves all at the same time.
Which is understandable. Lenski took an organism that reproduced very fast (because one of the issues with studying evolution is how long it takes to appreciate noteworthy change), while at the same time using a fairly low-complexity genome and removing as much extra complexity from the environment as possible so he could actually track the changes. It's pretty much the only way to go. If he would've kept the environmental changes you see in real life, he'll probably have ended up with much larger diversity and much harder to track population.
I didn't mean it as a metabolism slowdown, but as an extra step where they gather even more information from those frozen samples (my memory about that was a little fuzzy, but after reviewing Lenski's publications today due to what we're discussing, I can say I was wrong about them conducting experiments on one population at at time).
"how" in terms of what exactly? I was under the impression that it was, in simple terms, due to genetic mutations that helped whatever species in terms of survival of the fittest....
that being said, all 'living' things evolve for one purpose, and that is to flourish in a reproduction sense by surviving and adapting. Everything that we feel as a human, from physical pain to mental emotion can be sourced to evolution. Our perception of this world we live in, and our intellect and range of emotion is evolutionary advantageous to our species.
tl;dr - random genetic quality+advantage=evolution
- reproduction(surviving)=reason for evolution
Last edited by Proxy; 07-28-2011 at 09:09 PM.
Actually, the Newtonian model doesn't quite explain the celestial mechanics. It's been basically superseded by General relativity, which goes to greater details. In general, why such mechanics happen is due to gravity, a geometric property of space and time.
What I mean by 'fully explain how' is in terms of scientifically advancing some key theories from theory to law, by being able to fully verify them. Take natural selection. All of our observations point to being mostly correct about the functionality, but there's still too much work to be done to be able to predict the selection process by understanding all the mechanics involved.
"You ask why, I ask why not?"
Newtonian mechanics model large-scale dynamics well. Atomic-level stuff, not so much. General relativity is just another model.
All this still doesn't address my previous point.
Well, I do know that the words, 'theory' and 'law' are different in non-formal conversations, but in the science world, they are nearly identical. Theory, in scientific terms, does not point to lack of proof. The only difference law has, is that it can be proven in more terse examples... Evolution is fully verified, or it would still by a hypothesis.... tell me if I'm wrong, but that is my current understanding of the whole, theory vs law vs hypothesis argument.
Nothing comes to mind on what I've read on predicting the selection process, but I'll assume that would only be possible by studying and predicting whatever environment the subject was living in... from there I assume the studies of similar species' patterns would allow us to make reasonable scientific hypotheses... since the species that adapts to it's environment succeeds in the selection process... you would be predicting many things.
Like all things in science, if proven wrong, it will be discarded immediately. That hasn't happened for evolution. Evolution is set in stone just as deep as gravity is.
I addressed it. It happens so we can successfully reproduce.
Newtonian mechanics are still local. Not wrong, but simply inadequate to deal with the the variety of celestial mechanics that we can observe.
Sure it does. It's just another instance where the "how" explains the "why".
No religion I know of explains why either. You can ALWAYS ask why.
From a purely academic standpoint, an hypothesis is an idea that is not testable (such as ID). A theory (aka empirical hypothesis, scientific hypothesis) is an idea that proposes one or more testable propositions, sometimes some contingency for some of those propositions, and remains a theory until every proposition has been decided as true of real experience.
At that point, it stops being a theory and 'graduates' into a scientific law.
As far as the 'weight' a theory carries, it's really dependent on how many of those tests have been conducted, and been determined true. There's obviously some propositions that remain inconclusive for some time because there's no way to test them (only last year NASA was able to verify a claim in Einstein's theory of relativity). What makes theories like Relativity or Evolution stand out, is that even after new technology has come forward and allowed to test more of the claims, they've remained unfalsifiable.
Bottom line is that creating a theory that's FOS is really easy. I could make the same claims as ID, and propose that god is only observable when traveling at 3/4 the speed of light. It would be a 'valid' scientific theory that would remain inconclusive for a very, very long time. I don't particularly think the theory would gain much traction however.
Well, logically speaking, if you fully understand how selection operates, then given different scenarios, you should be able to predict what the outcome will be. Obviously, the complexity is mind boggling right now, but at some point 100 years ago, genetics was mind boggling too. The idea here is that actual significant advances are made when theories are either falsified or verified. So the more claims are verified the closer you get to the "how". The more claims that are falsified also advance the field, in that it makes you stop wasting time with an invalid proposition and forces you to reformulate it, which, in a way, also gets you closer to the definitive "how".
This just doesn't seem like your cup of tea.
By all means, knock yourself out. My post, now that I re-read it, seems a bit harsher than intended.
Better:
This discussion has gotten a bit long and convoluted, so it is hard to pick up in the middle and know what is going on.
I see.... the more you learn...
Should be mandatory reading.
http://www.notjustatheory.com/
no but that's because the law of sandwich artistry is scientifically sound.
for who?I think you unwittingly made a good point.
there are whole websites devoted to debunking, claim by claim, pretty much every claim that creationists have ever made.A theory never becomes a law. In fact, if there was a hierarchy of science, theories would be higher than laws. There is nothing higher, or better, than a theory. Laws describe things, theories explain them. An example will help you to understand this. There's a law of gravity, which is the description of gravity. It basically says that if you let go of something it'll fall. It doesn't say why. Then there's the theory of gravity, which is an attempt to explain why. Actually, Newton's Theory of Gravity did a pretty good job, but Einstein's Theory of Relativity does a better job of explaining it. These explanations are called theories, and will always be theories. They can't be changed into laws, because laws are different things. Laws describe, and theories explain.
Collectively creationists and the IDers who hope you don't notice that they are creationists, have consistantly made some real doozies.
The vast majority of the claims become readily apparent as deeply flawed or outright disengenuous.
When a group of people consistantly lie, show a poor grasp of the science involved, and/or state provably illogical things, then a pretty decent picture starts to emerge as to who is more likely to believe.
This is why ID and creationism lose consistantly in the courts. In the end, the science does not support creationism/ID, and one is left with religious dogma.
has science ever tried to answer the "why?" questions?
Those type of questions are usually reserved for religion, philosophy or history classes.
So, going all the way back to this, I will take PM's word that the physical copy of the article he has in his office, different than the online version, supplied him with the figure. So we have fact 3 supported, in some round about way.You mean tweak it like you tweaked it to make it conveniently *unfeasible*?
Let's dissect this here, as I think it is pretty symbolic of the kind and quality of arguments being made.
Facts stated:
1) "Two genes were altered in an asexual organism after 31,500 generations"
2) "there are over 40 million differences between our genome and the chimpanzee ‘next-of-kin’ genome…"
3) "it’s generally accepted that our lineages broke apart only 6 million years ago…"
Assumptions made to complete calculation:
1) Humans and bacteria mutate (add beneficial mutations) at the same generational rate, or 50% more (3 mutations as opposed to 2)
2) a human generation to be all of 20 years
Calculation:
20*31500= 630,000
I will grant, assumption #2, and fact #3.
The rest of it, will require some facts to be confirmed to fully see if this calculation has been "tweaked". I think the fatal assumption in this calculation is the first one, that an asexual bacteria will mutate as fast, generationally speaking, as a sexually reproducing (vive la difference!) human being. It is a very messy, flawed assumption, as far as I can tell.
Bull has been called. Back up fact 1 and 2, and show me on what you base assumption 1.
We will see who is tweaking what.
(edit)
Although it is ultimately YOUR responsibility to back up YOUR claims and assertions. If you can't, or won't, try after a few days, I will do so myself, so don't at me for getting something wrong, when you can't be bothered to back up your claims.
PM has also in some round about way stated that bacteria will mutate at a rate much faster than humans for a few reasons, on a per generation basis in any given single lineage. This will make his calculation a bit "generous". I will accede this, as I can buy his given reasons.
Now we get to the difference between "beneficial mutation" and "mutation".
The calculation here concerns "beneficial".
"Beneficial" had a very specific meaning in Lenski's experiment. It meant one thing, and one thing only. Did it increase the ability of the bacteria to reproduce on a medium with citric acid, and digest it.
If that were the ONLY "beneficial" trait that affected genes, that might mean something.
How many other "beneficial" genes were introduced that were not considered part of the experiment?
The environment determines what is "beneficial" and what isn't, for both humans and bacteria.
Evolutionary theory states that selective pressures are the other shaper of change.
Lenski very actively selected for only one trait.
Did past human environments only select for ONE trait and the genes that affected that trait?
Did the bacteria exibit other changes that would, in a more complex environment have also changed genes?
PM himself acknowledged that mutations happen all the time at VERY high rates for bacteria.
(repost, don't want it to get missed/buried) Gotta get going. That is enough for today
Right.
"The environment determines what is "beneficial" and what isn't, for both humans and bacteria."
The environment isn't be beneficial, it just is.
organisms strive to stay alive and reproduce, aka continuation of the species, in whatever environment.
If the environment changes, slowly or quickly, slightly or dramatically, the organisms that adapt successfully (changes in gene expression, etc), respond successfully to environmental stressors (changes in energy sources, water, temperature, colors) reproduce and organisms that don't adapt gradually weaken and die.
I think there is too much prominence give to random events, like from DNA replication mistakes, or radiation for outer space.
eg, 10Ms of people have lactose or gluten intolerance because they have failed to adapt to the change in nutrition presented by farmed food like cow's milk and grains that became available only several 1000 years ago.
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