[ippy]

Relationship between the development of the earth and the molecular evolution of life. Someone please explain it.

[asking]

The formation of the Earth the evolution of life are too different things.

The Earth formed millions of years before live originated on life. All the planets of the solar system formed from debris orbiting the sun, coalescing solid spheres, some with rings, some without. (See history of Earth at Wikipedia)

Pretty much as soon as the Earth cooled and the oceans formed--maybe 4 billion years ago? (I forget the exact date)--life appeared and began to evolve. (See timeline of life at Wikipedia.) How the first cells originated is not known, though there are several feasible hypotheses about how it could have happened. Molecular evolution is the process by which RNA began to carry information that could be transmitted to the next generation of cells. The information told the cells how to make certain proteins useful to the cells. (You can read about molecular evolution at wikipedia too.)

Later, the bacteria evolved and eventually formed eukaryotic cells, which have organelles, many of which are bacterial symbionts--smaller bacteria that came to live inside a bacterium. This is why chloroplasts and mitochondria have their own DNA. They were originally separate living entities. In time, the eukaryotic cells formed multicellular organisms, the jellyfishes, worms, etc. The rest is history.

[DUKE-OF-URL]

Hard to explain something that is not fact evolution is just a theory

[Capuchin]

In scientific usage, a theory does not mean an unsubstantiated guess or hunch, as it can in everyday speech. A theory is a logically self-consistent model or framework for describing the behavior of a related set of natural or social phenomena. It originates from or is supported by experimental evidence (see scientific method). In this sense, a theory is a systematic and formalized expression of all previous observations that is predictive, logical and testable.

The theory of evoution is agreed upon by the scientific community to be the VERY BEST model for how the myriad of biological variety we see today came about. Thus is gained the respectable title of a "theory" rather than a "hypothesis".

"just a theory" is something of an oxymoron, and shows complete ignorance on your parts.

[michealb]

Cap
I think the problem we keep running into is that most people know and trust a religious theorist, but almost no one knows a trusted scientist personally. So someone who has their absolute trust is telling them that science is wrong and you're just some guy on the internet, why would they believe you?

[DUKE-OF-URL]

Some people here believe in evolution lets just see what you believe in. can it be said you believe we crawled out of the water millions of years ago? Anyone want to pick up this ball?

[michealb]

While I personally didn't crawl out of the ocean, billions of years ago life did crawl out of the water. We even have similar animals today (Mudskipper) - Wikipedia, the free encyclopedia.

The reason evolution is a well accepted theory is because we can test and show it on a small scale. Granted no one has been able to observe changes over billions of years but we are able to extrapolate what would happen if our experiments were able to run longer. Let me give you an example of an animal put into two different situations, we will use an animal we all know very well for this example, man. Let's take breeding groups of people and put them into two very different situations. Group 1 will be in a situation that favors great mental ability but physical strength is not needed at all. Group 2 will be in situation that requires great physical strength but mental ability is all but useless. Now if we left these groups alone for several million years, when two were brought back together after so long they would not even recognize each other as having been once the same species. There would in fact be as much difference between the two as the mountain gorilla today and man if not more.

[asking]

The New Republic has an excellent review of Michael Behe's new book. Behe is also the author of Darwin's Black Box, a book that attacks evolutionary biology. Since Judge Jones' decision in the Dover, Pennsylvania trial over whether a school board could force biology teachers to teach creationism or ID (I think), Behe--who is the principal proponent of ID with an academic appointment-- has backtracked amazingly and now basically accepts all of evolutionary theory in his new book. The only part he rejects is the idea that mutations occur without being necessarily good for organisms--they can be good or bad. Behe now says that all of evolution is right, but that mutations, the changes in DNA that make organisms unique and different from one another, are put there by God. The book review, by an evolutionary biologist, is very good and provides a good explanation for why Behe is still wrong. You can read it here. The New Republic makes you register, but you can still read it for free. The Great Mutator: http://www.tnr.com/doc.mhtml?i=20070618&s=coyne061807

http://www.tnr.com/doc.mhtml?i=20070618&s=coyne061807

[asking]

[QUOTE=michealb]While I personally didn't crawl out of the ocean, billions of years ago life did crawl out of the water. We even have similar animals today (Mudskipper) - Wikipedia, the free encyclopedia.

The reason evolution is a well accepted theory is because we can test and show it on a small scale.

Also, evolutionary biology has made predictions that have been confirmed over and over, a point that Jerry Coyne makes in the article about Michael Behe's new book, which I mentioned elsewhere in this thread. A good scientific theory makes predictions. If the predictions are repeatedly confirmed, it's a good sign that the theory is correct. This is the case with both evolution, gravity, and the idea that DNA carries genetic information. They are all about equally accepted by scientists.

[DUKE-OF-URL]

While I personally didn't crawl out of the ocean, billions of years ago life did crawl out of the water. We even have similar animals today (Mudskipper) - Wikipedia, the free encyclopedia.

The reason evolution is a well accepted theory is because we can test and show it on a small scale. Granted no one has been able to observe changes over billions of years but we are able to extrapolate what would happen if our experiments were able to run longer. Let me give you an example of an animal put into two different situations, we will use an animal we all know very well for this example, man. Let’s take breeding groups of people and put them into two very different situations. Group 1 will be in a situation that favors great mental ability but physical strength is not needed at all. Group 2 will be in situation that requires great physical strength but mental ability is all but useless. Now if we left these groups alone for several million years, when two were brought back together after so long they would not even recognize each other as having been once the same species. There would in fact be as much difference between the two as the mountain gorilla today and man if not more.

No it's a well excepted theory because your and my tax dollars are paying for it to be taght as fact in the public school system.

Also it is well eccepted because the only other road is creation and if they believe that it means they also have to except God and all that that means.

But lets get back to the subject lets regress back before your anccestor crawled out of the water where did this stuff all come from?

Please realize that I am coming from a non attacking position here we are just talking.

[michealb]

No its a well excepted theory because your and my tax dollars are paying for it to be taght as fact in the public school system.

Also it is well eccepted because the only other road is creation and if they beleive that it means they also have to except God and all that that means.

But lets get back to the subject lets regress back before your anccestor crawled out of the water where did this stuff all come from?

Please realize that I am coming from a non attacking position here we are just talking.

It's not well accepted by the american public in fact the only country that believes more in creationism than the US is Pakistan. It is accepted by the scientific community just like gravity is a well accepted theory. Some polls put it as high as 72% of americans disagree with evolution.

When the whole ID hypothesis came out, I will admit that I was persuaded, at the time I hadn't done any research and on the surface it sounds a lot easier to believe. I spent a year reading subject material on both sides. Only after I had done a year of research was I able to fully understand how evolution works and why, so I don't expect to be able to sum it up for you here.

As far as where the original living cells came from you have me there. I have read studies where scientist replicated what earth would have been like when the earth first formed and were able to get ammino acids to form with some other building blocks of life but weren't able to create life in that experiment. My guess is that those chemicals need to be stirred for a few million years before they get randomly put together to form a living cell. I haven't done much research in this area perhaps someone else on the board has.

[talaniman]

If you can accept the Creator as a master scientist then creation, and evolution are easy to understand. As man learns more he will evolve and adapt, and hopefully continue to grow. Then he can solve the mysteries that confront him. Barring extreme catastrophy, I have seen no scientific data anywhere that conflicts with The Creator and his plan of evolution.

[asking]

As far as where the original living cells came from you have me there. I have read studies where scientist replicated what earth would have been like when the earth first formed and were able to get amino acids to form with some other building blocks of life but weren't able to create life in that experiment. My guess is that those chemicals need to be stirred for a few million years before they get randomly put together to form a living cell. I haven't done much research in this area perhaps someone else on the board has.

I didn't understand what the question was. There is considerable theoretical work on this idea, how the first cells formed, and even some interesting experiments. Scientists have put together several plausible explanations. One is that cells formed here on Earth with simple cell like lipid spheres (like our own cells) with RNA molecules that coded for enzymes that broke down molecules in the ocean (or whatever water they were in, maybe warm pools of water on rocks) and got energy (food) from those molecules. Another theory, called panspermia, I think, says that maybe the first cells came from somewhere else and comets full of these cells seeded the Earth's oceans. I don't think that theory is very popular anymore. Most biologists accept that cells somehow formed here on Earth. It could not happen today, because a cell that formed de novo (out of nothing) would not have the adaptations that modern life has and would be eaten by something immediately. But early Earth may have been a more hospitable place for such half formed cells.

The origin of life is a VERY different question from evolution--change over time and the multiplication of species. Evolution is not doubted by any practicing biologist that I know of. But how the first cells arose is a much harder question and I don't think anyone can say for sure that life absolutely formed one way or another. We do know that all of life shares characteristics that go back to these early cells, though. Just like a family might all have similar traits, the family of living organisms share a lot of traits. Wikipedia has entries at Origin of Life and RNA World. <http://en.wikipedia.org/wiki/RNA_world_hypothesis> that might be helpful...

[Capuchin]

The main problem with working out how biogenesis occurred is that we don't know what kind of environment the Earth was billions of years ago. I feel this is one of the limiting factors that stops us from producing it in the lab.

[sovaira]

For evolution to take place it is very essential to begin from micro level,, then to macro ones as it eventually reaches that point... but first evolution begins at molecular level.

[DUKE-OF-URL]

Pierre-Paul Grasse of the French Academy of Sciences writes, “ No matter how numerous they may be, mutations do not produce any kind of evolution.” Molecular biologist Michael Denton says, “The failure to validate the Darwinian model has implications which reach far beyond biology.” Information theorist Hubert Yockey writes,” One must conclude that, contrary to the established and current wisdom, a scenario describing the genesis of life on earth by chance and natural causes which can be accepted on the basis of fact and not faith has not yet been written (Information Theory and Molecular Biology. Cambridge University Press, Cambridge). Ferguson says, “Scientists are particularly loath to relinquish the last form of prejudice.. . It must be true because anything else would be unthinkable.” For example, Dawkins says, “.. . The only alternative explanation of the sudden appearance of so many complex animal types in the Cambrian era is divine creation, and [we] both reject this alternative. (The Blind Watchmaker, 1986, pp 229-230).

[Capuchin]

Pierre-Paul Grasse of the French Academy of Sciences writes, “ No matter how numerous they may be, mutations do not produce any kind of evolution.”

As you seem to agree, microevolution is incredibly observable in bacteria species, and we see that members with particular mutations that prevent them from being killed by anti-biotics live on and form a new resistant version of the species.

Molecular biologist Michael Denton says, “The failure to validate the Darwinian model has implications which reach far beyond biology.”

Sure, we don't use the darwinian model, we use darwin's ideas and tweak them so that they conform to the evidence even better. That's exactly what science is about.

Information theorist Hubert Yockey writes,” One must conclude that, contrary to the established and current wisdom, a scenario describing the genesis of life on earth by chance and natural causes which can be accepted on the basis of fact and not faith has not yet been written (Information Theory and Molecular Biology. Cambridge University Press, Cambridge).

Completely true, that doesn't say anything for or against evolution though. Just biogenesis.

Ferguson says, “Scientists are particularly loath to relinquish the last form of prejudice . . . It must be true because anything else would be unthinkable.” For example, Dawkins says, “ . . . the only alternative explanation of the sudden appearance of so many complex animal types in the Cambrian era is divine creation, and [we] both reject this alternative. (The Blind Watchmaker, 1986, pp 229-230).

(Which Ferguson?) You realise that exactly the same can be said with millions of times more evidence about creationists, right?

[asking]

[QUOTE=DUKE-OF-URL]Pierre-Paul Grasse of the French Academy of Sciences writes, “ No matter how numerous they may be, mutations do not produce any kind of evolution.”

I read a nice metaphor recently, that natural selection is the engine that drives evolution and mutations are the fuel that powers that engine. Mutations themselves are not evolution, but the variation that they produce is what allows natural selection and evolution to happen. It's important to understand the difference between evolution (which is change over time) and natural selection (which is the differential reproduction of different genotypes). They are two separate things. Evolution is the result. Natural selection is the process that allows evolution to occur over time. During evolution, organisms change over generations, accumulating new traits, losing old ones. Some become more complex; some become simpler; and some stay the same.

Some people have the mistaken idea that because mutations are described as "random," that evolution is random. But evolution is not random at all. Natural selection is pretty much the opposite of random. Only mutations are in any sense random and only in a way. Some genes change (mutate) more easily than others. And stressed organisms may produce sperm or eggs with more mutations than unstressed ones. So the mutation rate may actually respond to the environment. But a mutation occurs regardless of whether it will help or hurt the organism. In fact, it could help in one environment and hurt in another. (Or it could be bad no matter what.) So mutations are contingent on circumstance. In that way they are random, a matter of luck.

Organisms retain thousands of variants, old mutations that persist in the populations, from which natural selection can "choose." Most evolution is working with pre-existing variants, not new mutations that just occurred in the previous generation. Evolution would be impossible without mutations, but they are not evolution.

Hope this helps.

[albear]

( I don't know if anybodys posted this before me) maybe you could talk about when the earth developed to form continents selective evolution happened to the species so that they could survive better in the newly formed habitat, darwin's finch theory,

[asking]

( i dont know if anybodys posted this before me) maybe you could talk about when the earth developed to form continents selective evolution happened to the species so that they could survive better in the newly formed habitat, darwin's finch theory,

Right. Biogeography is a really persuasive line of evidence that supports the idea of evolution. But most people find it harder to explain and to understand. Also, it's not as popular these days because it doesn't relate to molecular biology (I think).

By the way, how to get I quotes in those nice little boxes, instead of in markup?

Just Asking