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 susan_cd
Joined: 5/16/2007
Msg: 610
Evolution. Page 25 of 64    (24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64)

Assuming there are 1022 planets in the universe (a very large number: 1 with 22 zeros following it), his answer is shocking: one chance in 10138-that's one chance in one with 138 zeros after it! There are only 1070 atoms in the entire universe. In effect, there is zero chance that any planet in the universe would have the life-supporting conditions we have, unless there is an intelligent Designer behind it all."


"Assuming" ? If there are no hard facts and calculations are going to be made by assuming numbers & the running them thru a formula then the outcome (of the calculations ) is meaningless. The old GIGO acronym comes to mind, "garbage in, garbage out".
 susan_cd
Joined: 5/16/2007
Msg: 611
Evolution.
Posted: 3/3/2010 12:05:43 PM
^^^^^ Carl Sagan demonstrates this point well in the series & book Cosmos, when he discusses early astronomers viewing Venus thru a telescope:


Venus was evidently covered by a dense layer of obscuring cloud. When we look at the planet in the morning or evening skies, we are seeing sunlight reflected off the clouds of Venus. But for centuries after their discovery, the composition of those clouds remained entirely unknown.

The absence of anything to see on Venus led some scientists to the curious conclusion that the surface was a swamp, like the Earth in the Carboniferous Period. The argument - if we can dignify it by such a word - went something like this:

‘I can’t see a thing on Venus.’
‘Why not?’
‘Because it’s totally covered with clouds.’
‘What are clouds made of?’
‘Water, of course.’
‘Then why are the clouds of Venus thicker than the clouds on Earth?’
‘Because there’s more water there.’
‘But if there is more water in the clouds, there must be more water on the surface. What kind of surfaces are very wet?’
‘Swamps.’
And if there are swamps, why not cyacads and dragonflies and perhaps even dinosaurs on Venus?

Observation: There was absolutely nothing to see on Venus.

Conclusion: It must be covered with life. The featureless clouds of Venus reflected our own predispositions.
 Verzen
Joined: 12/9/2007
Msg: 612
Evolution.
Posted: 3/3/2010 3:24:30 PM
Ron - The second law of thermodynamics only pertains to CLOSED SYSTEMS.
 stargazer1000
Joined: 1/16/2008
Msg: 613
Evolution.
Posted: 3/3/2010 3:24:55 PM

While there is a lot of evidence of evolution occuring, there are some gaps that have yet to be explained. So, focusing on those gaps doesn't make me wrong, it just makes me one who still questions. Being able to "explain" how some things of a theory happen doesn't necessarily make a theory right if there are other parts missing.

And, since there are pieces missing, I am willing to wait until more of the puzzle is "found"..............


Sufficient evidence for evolution as presently understood exists to make evolution the default explanation for the origin of species. It does a fine job at explanation the evidence of the fossil record. It also does a fine job at explaining things like the development of new strains of pathogen.

Are there things that still need explaing? Of course. But, so far, there is nothing that does as good a job as the theory of evolution and, until it comes along, evolution is the means by which we will continue to explain the development of life.
 RocketMan_Len
Joined: 7/5/2006
Msg: 614
Evolution.
Posted: 3/3/2010 4:04:11 PM

You can't have a creation without a creator.


Then what created the Creator...?
 RocketMan_Len
Joined: 7/5/2006
Msg: 615
Evolution.
Posted: 3/3/2010 5:10:33 PM

But what if the Creator always was?


That statement could equally be applied to the Universe - it always existed, and thus does not NEED a Creator.
 susan_cd
Joined: 5/16/2007
Msg: 616
Evolution.
Posted: 3/3/2010 5:28:37 PM

But what if the Creator always was? Or do you think that our time encompasses all?


But what if the Creator wasn't always? For the purposes of this discussion/debate my question is as valid as your question ( said validity being zero, since neither question is testable).

Time and space are attributes of this physical universe only.

It's impossible to know that, you're making a generalization. In any event, since this physical universe is the only one we CAN observe then suggesting conditions are (or may be) different in some hypothetical universe we can't observe, enter, measure or even know exists adds nothing to this discussion.


Eternity isn't an infinite amount of time.


Actually, by definition that's exactly what eternity is:


e·ter·ni·ty /ɪˈtɜrnɪti/
–noun
1.infinite time; duration without beginning or end.
2.eternal existence, esp. as contrasted with mortal life: the eternity of God.
3.Theology. the timeless state into which the soul passes at a person's death.
4.an endless or seemingly endless period of time: We had to wait an eternity for the check to arrive.



As this thread is about evolution we can exclude definitions 2 & 3... number 4 is meant as an artistic/poetic/specious useage. That leaves definiton # 1 "infinite time".
 desertrhino
Joined: 11/30/2007
Msg: 617
view profile
History
Evolution.
Posted: 3/3/2010 6:15:10 PM
OR, there is a basic flaw in the underlying premises upon which our cosmological theories are based.

Reckon we'll see.
 rockondon
Joined: 2/21/2007
Msg: 618
view profile
History
Evolution.
Posted: 3/3/2010 8:00:26 PM

As unlikely as it is for a planet to acquire life, it must have happened here, because here we are. Why did something so unlikely happen?
I've already refuted the old odds argument 5 different ways on the last page but just for fun, just imagine the likelihood that life would happen after one trial. Think of a number that you think is reasonable odds for such an unlikely event.
Now imagine countless planets in the galaxy and the countless trials on each of those planets occurring simultaneously for countless years. Eventually, one of those trials creates a very simple polynucleotide, formed of atoms that naturally attract and bind together, and that very simple polynucleotide replicates itself - and bang - you got life. That unlikely event suddenly seems very likely - and of course since we're here talking about it its a certainty.

Now that you see how simple it is for an unlikely event to occur when given enough trials, imagine the odds of a supernatural being casting magic spells to poof the world into existence. Exactly zero.

One thing that I've never understood is why some people (creationists and intelligent design advocates) think that it's necessary to believe that life was created, and evolved, in contravention of the physical laws of this universe.
I completely agree.
Not only are creationists oblivious to evolution, they insult their god by lying about his creation.
 aremeself
Joined: 12/31/2008
Msg: 619
view profile
History
Evolution.
Posted: 3/3/2010 9:15:10 PM
hey paul,

give me one, please, just one that is proof in your eyes sir.
 stargazer1000
Joined: 1/16/2008
Msg: 620
Evolution.
Posted: 3/4/2010 5:37:54 AM

But, there are plans to use more sophisticated detectors that will be able to probe the Universe by other means. These include neutrino detectors, gravitational wave detectors and hydrogen 21 cm radiation detectors, tuned to detect the weak afterglow of the Big Bang, much like Cosmic Background Radiation (but apparently even more detailed).


Actually, the universe is already visible at 21 cm through standard radio receiving equipment. As for neutrino detectors, well, they too already exist, as do probes of the CMB and gravity waves.

As for the size of the universe, our visible horizon gives us an timescale of 13.7 billion years since the big bang.

As for the "universe is a fractal" idea floating around, I really don't understand what that is supposed to mean or what the significance is supposed to be. Fractal structures do exist...tree branches, seashells, clouds. But that doesn't mean the entire universe "is a fractal."

That seems to me to be one of those things where people go "Hey, fractals are cool. So is the universe. So the universe is a fractal! Cool!"
 aremeself
Joined: 12/31/2008
Msg: 621
view profile
History
Evolution.
Posted: 3/4/2010 11:00:12 PM
sorry paul, I thought I had your quote in there. [I am careless that way]


in your message 1273.

While there is a lot of evidence of evolution occurring, end of quote.

just wondering what you meant, that's all.
 aremeself
Joined: 12/31/2008
Msg: 622
view profile
History
Evolution.
Posted: 3/5/2010 7:46:49 PM
ahh, you don't personally have any of this evidence, you are leaving that up to the others.
dangerous thing to do.

now you are surprising me.

you fight the political, economic thing tooth and nail, but will take others word for evolution.

your are sensible in a lot of ways, I was awful curious as to what your evidence was, oh well.

Ok, now I know, no big deal.
 stargazer1000
Joined: 1/16/2008
Msg: 623
Evolution.
Posted: 3/5/2010 8:08:40 PM

ahh, you don't personally have any of this evidence, you are leaving that up to the others.
dangerous thing to do.


No more dangerous than relying on others' assurance that humans are the result of the will of an unseen supernatural being.
 aremeself
Joined: 12/31/2008
Msg: 624
view profile
History
Evolution.
Posted: 3/5/2010 8:11:35 PM
I have no argument with that at all, stargazer.
 aremeself
Joined: 12/31/2008
Msg: 625
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History
Evolution.
Posted: 3/5/2010 8:20:50 PM
Paul

you might not want to make the time, but you can actually google all of that stuff.
 aremeself
Joined: 12/31/2008
Msg: 626
view profile
History
Evolution.
Posted: 3/5/2010 10:00:24 PM
yes, what triggered certain changes.
what specific change do you have in mind?

start with one and only one, or it gets confusing.

you will have to analyze each bit of information and find out if it is fact or postulation. have fun.
you will maybe find a trend.

results of built in adaptation and programing is taken as evolution.
make up your own mind on all of it.

get the evolution guys to explain it and give you links, mine will be considered to be biased.

origin of matter? no, no proof.
big bang works for me.
doesn't matter really.

did you check the 4 main laws of physics?
that will help you some.

it all starts with a thought that won't go away.

sounds like you have one.
 FrogO_Oeyes
Joined: 8/21/2005
Msg: 627
view profile
History
Evolution.
Posted: 3/6/2010 8:56:24 AM

It is like looking at a series of buildings, going from short to tall, and declaring that all buildings were once small, and then evolved into tall buildings.

It really isn't, though I can appreciate this view coming from anyone without an extensive knowledge of the subject matter. The evidence of increasing complexity is there, as is evidence for how that increase occurs.


For example, was the change a result of radiation from the sun, or even perhaps from too many X-rays............ ?

In relation to this statement, the answer to the first question is "no". However, the portion I have quoted is actually largely irrelevant.

There are many causes for genetic change, most of them mundane and routine. The latter is what makes genetic change so abundant. DNA is a chemical compound. It undergoes chemical reactions, which is necessary in order for duplication and reproduction to take place. Although chemical reactions follow rules, there is still a fair amount of chance involved. Consequently, mistakes happen frequently.

Two good examples are cytochrome-B and mitochondrial DNA [both of which I have likely discussed previously in this very thread]. Cyt-B is a large complex molecule, encoded by a large and complex segment of DNA. It can undergo large amounts of random changes without suffering any change in how it works. That makes it useful as a "clock". Differences can be measured in the gene for Cyt-B in many organisms, whether siblings or only distant evolutionary relatives. Based on reproductive rates of the living organisms and their kin [the main factor behind rates of genetic change], those differences can be equated to years, and then compared with fossil evidence and other genes for confirmation. Much the same applies to mtDNA, except that it is inherited only from the mother. Genetic material like these provide an excellent means of showing not only the time since a last common ancestor, but that organisms DID have a common ancestor. They also show how quickly and routinely genetic changes happen and accumulate. In smaller or more critical genes, this might be harder to see, because lethal or deleterious mutations might be more likely. That means there would be a bias in which changes are present, and there could be many instances of "false positives". That is, a change from thymine to cytosine might easily be changed back. That will happen in any gene, but the liklihood drops drastically in large genes.

Now, more directly to your question and the thought processes behind it...

The changes are largely random, in that they are not targeted towards a particular outcome. It is what the altered gene does to the organism which skews the randomness. The question is not "why did the hair change from straight to curly", but "why did that change persist in the population?" Random genetic change answers the first. Genetic isolation and/or a selective advantage answer the second. BOTH of these are often testable experimentally or observationally. It's not unusual for an observed trait to NOT be the critical feature. Rather, what we observe is often a side-effect of something else which is fundamentally more important. For example, sickle cell anemia is a disease which is easily observed. However, this is essentially a side-effect of a gene for malaria resistance. In this case, the effects and side-effects are observed in different individuals. The color and pattern of isolated populations of lizards can often be correlated with the color and pattern of substrate and assumed to be efficient camoflage for the habitat. This can be tested by comparing different appearing relatives on both their normal and alternate habitats, and measuring predation rates. In variable geckos, such a comparison can be made by examining how many of each are missing pieces of tail. Typically, the inherited color pattern which best matches the background will have fewer broken tails, because they are better at escaping predators.

Returning to your last question - yes, it is often quite easy to determine what advantages were provided by a particular mutation. Tracking the cause of the genetic change itself however, is both tricky, and largely unimportant. Such changes are random, not directed towards a particular result. There are often exceptions to the rules, but even so, they do not establish the overall patterns. Any examples I can think of are purely hypothetical.
 stargazer1000
Joined: 1/16/2008
Msg: 628
Evolution.
Posted: 3/6/2010 11:15:42 AM

I have no argument with that at all, stargazer.


And yet, you yourself have said you believe we were "created."

Contradiction. You have no more proof of "creation" or "design" than you accuse 'evolutionists' for lack of a better word of having for that mechanism.
 FrogO_Oeyes
Joined: 8/21/2005
Msg: 629
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History
Evolution.
Posted: 3/6/2010 11:16:27 AM
It seems to me that if you tracked the CAUSE of genetic change, then you might be able to figure out how do accomplish that in a lab

We've been causing genetic change in the lab for decades, by a variety of methods, down to and including changing specific portions of specific genes. Old news, and the origin of terms like "GMO" and "genetic engineering".

Causing specific genetic change is not a problem. The issue is relating specific changes to specific outcomes. Sometimes this is possible and straightforward, and sometimes it's virtually impossible. In the latter case, the reason is that many genes do NOT code for specific observable features. Those features are actually the result of long chains of chemical interactions encoded by a wide variety of different genes, as well as physical interactions between the organs. This is where the fields of "genetics", "embryology", and "biochemistry" overlap. For example, the shapes of bones are only partially determined directly by genes. Otherwise, they are formed by cells which react to the chemistry of surrounding cells, and by the strains induced by developing muscles and tendons.


as that is where actual "evolution'' takes place.

This is where the change and the inheritance takes place, but it is not where selective pressures are applied. Those pressures apply to the phenotypes, the more superficial traits of the organism. The organism and its reproduction are selected by the environment. Genes are selected indirectly, by whether or not the organism lives and breeds.

how complex DNA really is, in that it has built in "clocks", among other things,

You're misunderstanding. The "clocks" in this case are only from OUR perspective. Genetic changes occur at random, but they occur often enough as to have a regular and measurable rate - just like radioactive decay. Some changes are lethal or destructive, and we won't be able to observe them in a living organism. That throws off the accuracy of our rate estimates. However, there are a number of very large genetic regions which can and do experience change without harm. We use those regions to get accurate estimates because the chance of a change NOT being observed is extremely low.

Maybe I should give a quick intro to how it works, in slightly simplistic fashion...

Using cytochrome-B, we look at 1000 base pairs from a stable region of the gene. "Pairs" because DNA is made up of two chemically-matched strands. A change on one strand is normally mirrored in the other strand because the two sides are bonded together - Cytosine always with thymine, adenine always with guanine. Cyt-B is actually much bigger, but some regions are more stable than others. Moving on... We sample lets say 1000 humans. On average we find that they differ from their parents by one base pair. Assuming an average and steady rate of reproduction [we normally can, and can adjust when we think otherwise] at one generation every 20 years, we have a measurable rate of change of 1 base pair per 20 years. To test this, we now sample populations where we KNOW how many years separate them. If the last shared ancestor was 2000 years ago, there should be an average of 100 base pairs difference. Bingo! It works quite well, and estimates can go back millions of years for many organisms. Obviously, it's harder to confirm reliability at those ages, but since the method itself is reliable, we have no cause to doubt it. Additionally, we can use many other genes to do the same thing, and see if they produce more or less the same result. That can then be correlated against other things, such as geological evidence of when two land masses were last in contact. Frequently, the genetic estimates match up with times for geological barriers appearing - rift valleys, volcanic eruptions, etc.

We call them genetic clocks not because they schedule anything, but because we can use their rates of change as time estimators.


in that it has built in "clocks", among other things

It actually does in some ways, but they're not so much timers as they are systems which break down at a certain point. Aging is likely one example, in which deterioration occurs more steadily as the organism reaches a point of not reproducing. Simply, if faulty genes don't show their effects until after the best reproductive years, they will continue to be passed on to offspring. An individual who does NOT have any such genes, could theoretically reproduce as long as he lived, and these non-aging genes would spread rapidly in the population. This is true of some organisms, such as certain plants and single-celled organisms which effectively clone themselves.


and to try to imagine that all of that happened just by circumstance, and persisted for all of the time of life is off the charts.

Fallacious reasoning however. Appeal to numbers, appeal to personal incredulity, and more. In any case, it's based on a misunderstanding of the molecular clock concept. The statements which follow are fruit of the tainted tree.


currently is, all the while facing the same odds of de-evolving, getting less complex, or not working at all, as it did of evolving into something more complex.

No.
First, no such thing as de-evolving. This has been pointed out many times already.

ANY inherited change is evolution, regardless of whether complexity increases or decreases. Sometimes there are advantages to be had from simplification. There are many parasites, for example, which evolved from more complex organisms. Since the host provides digestion, stable environment, etc, the parasite saves a lot of effort by not developing all the traits of its ancestors. Troglobites, stygophiles, paedomorphs, and neotenes may all experience some degree of simplification due to restrictive and stable environments.

Second, the chances are NOT equal. Changes which do not improve an organisms chances of reproducing, will tend to be weeded out quite quickly. This is the evolutionary arms race. Predators, parasites, competitors, and mates are all part of the natural selection process. The gazelle which becomes SLOWER is eaten long before if can breed. The human with a simplistic immune system dies from parasite or disease damage. Complexity increases in the biosystem for the same reason it does in military technology - for the most part, performance is NOT improved by removing features, but by adding them.
 aremeself
Joined: 12/31/2008
Msg: 630
view profile
History
Evolution.
Posted: 3/6/2010 11:32:14 AM
stargazer

read your own quote


No more dangerous than relying on others' assurance that humans are the result of the will of an unseen supernatural being

when have I shown that I predominantly relied on others?

AND have you positively ruled out other dimensions?
why?
because our very limited science says so?

or, because you just know?
 stargazer1000
Joined: 1/16/2008
Msg: 631
Evolution.
Posted: 3/6/2010 12:47:25 PM

when have I shown that I predominantly relied on others?


Ah, so you came up with your views on humans "creation" entirely independent of external cultural influence? You've never encountered the subject of divine creation? You have done all the science that leads you to a view away from the standard model of evolution entirely on your own?


AND have you positively ruled out other dimensions?
why?
because our very limited science says so?


No, but where's the relevance in the current discussion? What does the possible existence of other dimensions have to do with the evolution of life on the planet except as a means to muddy the water?
 susan_cd
Joined: 5/16/2007
Msg: 632
Evolution.
Posted: 3/6/2010 2:08:32 PM

No matter what dictionaries say, Eternity properly means that which is outside of time, and doesn't mean an infinite amount of time.



I guess if you're going to deny dictionaries give the accepted definitons of words it's a small step to denying any facts you may find uncomfortable or that you don't agree with.
 aremeself
Joined: 12/31/2008
Msg: 633
view profile
History
Evolution.
Posted: 3/6/2010 5:14:42 PM
star


you bet that I have my own views!
I can't emphasise that enough!
thanks for noticing!


in asking me that, you are admitting that you don't.

sorry, didn't mean to muddy the waters, but feel free to answer that question.
 stargazer1000
Joined: 1/16/2008
Msg: 634
Evolution.
Posted: 3/8/2010 7:35:35 AM
Oh hey! Evolution studied in a laboratory!

http://www.sciencedaily.com/releases/2009/10/091018141716.htm


Time In A Bottle: Scientists Watch Evolution Unfold
ScienceDaily (Oct. 19, 2009) — A 21-year Michigan State University experiment that distills the essence of evolution in laboratory flasks not only demonstrates natural selection at work, but could lead to biotechnology and medical research advances, researchers said.

Charles Darwin's seminal Origin of Species first laid out the case for evolution exactly 150 years ago. Now, MSU professor Richard Lenski and colleagues document the process in their analysis of 40,000 generations of bacteria, published this week in the international science journal Nature.

Lenski, Hannah Professor of Microbial Ecology at MSU, started growing cultures of fast-reproducing, single-celled E. coli bacteria in 1988. If a genetic mutation gives a cell an advantage in competition for food, he reasoned, it should dominate the entire culture. While Darwin's theory of natural selection is supported by other studies, it has never before been studied for so many cycles and in such detail.

"It's extra nice now to be able to show precisely how selection has changed the genomes of these bacteria, step by step over tens of thousands of generations," Lenski said.

Lenski's team periodically froze bacteria for later study, and technology has since developed to allow complete genetic sequencing. By the 20,000-generation midpoint, researchers discovered 45 mutations among surviving cells. Those mutations, according to Darwin's theory, should have conferred some advantage, and that's exactly what the researchers found.

The results "beautifully emphasize the succession of mutational events that allowed these organisms to climb toward higher and higher efficiency in their environment," noted Dominique Schneider, a molecular geneticist at the Université Joseph Fourier in Grenoble, France.

Lenski's long-running experiment itself is uniquely suited to answer some critical questions -- such as whether rates of change in a bacteria's genome move in tandem with its fitness to survive.

"The coupling between genomic and adaptive evolution is complex and can be counterintuitive," Lenski concluded. "The genome was evolving along at a surprisingly constant rate, even as the adaptation of the bacteria slowed down a lot. But then suddenly the mutation rate jumped way up, and a new dynamic relationship was established."

A mutation involved in DNA metabolism arose around generation 26,000, causing the mutation rate everywhere else in the genome to increase dramatically. The number of mutations jumped to 653 by generation 40,000, but researchers surmise that most of the late-evolving mutations were not helpful to the bacteria.

Gene mutations involved in human DNA replication are involved in some cancers. Many of the patterns observed in the experiment also occur in certain microbial infections, "and cancer progression is a fundamentally similar evolutionary process," observed collaborator Jeffrey Barrick. "So what we learn here can help us better understand the course of these diseases."

Barrick, a postdoctoral researcher in MSU's Department of Microbiology and Molecular Genetics, developed computational tools to discover and validate often complex mutations. "We know an astounding amount about the details of evolution in these little Erlenmeyer flasks," he said.

The Nature paper involved collaboration with scientists from South Korea as well as France and MSU. The research, said genomics team leader Jihyun Kim of the Korea Research Institute of Bioscience and Biotechnology, "is not only useful in understanding the tempo and mode of evolution, but can serve as a nice framework for practical applications in biotechnology, such as improving the performance or productivity of an industrial strain."

Thousands of generations later, the MSU experiment continues to evolve. "Like a lot of science, our study answers some questions but raises many others," Lenski said.
The research has been supported by the National Science Foundation and the Defense Advanced Research Projects Agency.
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