How do you define the word Evolution?

He's already admitted he doesn't - he's resentful that science has noticed how species work.I was thinking about this earlier; evolution was a discovery not an invention, there was no way it wouldn't be noticed by enquiring minds. And to any reasonable mind, it's both obvious and wonderful.There's stacks of practical uses for the ToE - I was only reading today how ecololgy uses it to predict the outturns of environmental changes, but even if it had no practical value whatsoever, it's an amazing thing in of itself. I have a feeling that like the people that mapped the stars movements before it had any practical value, the uses of the ToE are only just beginning to emerge.

Really pisses you off, huh?I don't think it's good for you to carry around that much anger. We're here for you, let it all out.ABE: I read this part again and wanted to comment. Well, in my own study and reading, "that all life evolved from a common ancestor", is not the theory, but a rather the inescapable conclusion of ALL the observations that the Theory of Evolution describes, about 150 years of observations.If you want to overthrow that, you need to up your game a whole bunch.Edited by Tanypteryx, : Added more pith.

I think what you're getting at stems from the fact that applied biology is basically really complex chemistry and the evolution of populations is on a more macro-scale than that.The Theory of Evolution can be used in applied biology, but not all of applied biology depends on it. No, no, no... you don't get to do that. The way biologists are using the word evolution is the way it should be defined. You don't get to say that it really means something else. That's not true. The science of Biology does depend on the Theory of Evolution. It explains so much and it is very useful. Biology cannot still be 100% without it. Okay, you're talking about "all life evolved from a common ancestor". That is not the Theory of Evolution.A Last Universal Common Ancestor of all of modern life is a particular ramification of an application of the Theory of Evolution that is based on factual data, but it isn't something that has a conclusive consensus. Wait, then why are you talking about it?What other useless things do you talk about a lot? That was cute.

Seems a bit strong of a claim, to me. There's some weird shit out there... And have we even found it all?

Where do you get the nonsensical idea that something requires experiment in order to be science?(That's a rhetorical question, as its strictly creationists pushing this "experiment" idea so as to discredit fields of science that contradict their religious beliefs.)All science needs is observations, and from those observations scientists can devise hypotheses and test them against future observations. Hypotheses which make successful predictions and survive the tests can evolve into a theory.In science, it is the theory which organizes and explains the observations.

Well, you may be correct. I should have said "that all life evolved from a common ancestor or a group of common ancestors , is not the theory, but a rather the inescapable conclusion of ALL the observations that the Theory of Evolution describes, about 150 years of observations.Do you think the ToE describes observations that show something different? That's the truth! I have seen Damselflies that mimic butterflies and tiny parasitoid wasps that look like little robotic machines. I could spend days telling you about all of them. Not even close. We've described most of the stuff bigger than a boot, but probably not more than 10% of the total species (my personal estimate). We have done well with vertebrates, but most of the life on this planet is invertebrates. Earth is the cradle of invertebrates. They make up 33 of the 34 phyla.

Not right now, no. I just don't think it is conclusive that ALL life has a common ancestor.I would agree that, currently, we do not have data or observations telling us otherwise, but we might have some candidates or there might be something different out there that we haven't found yet.For example, they found some really weird microbes in a cave:

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In a Mexican cave system so beautiful and hot that it is called both Fairyland and hell, scientists have discovered life trapped in crystals that could be 50,000 years old.

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The bizarre and ancient microbes were found dormant in caves in Naica, Mexico, and were able to exist by living on minerals such as iron and manganese, said Penelope Boston, head of NASA's Astrobiology Institute. .

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"It's super life," said Boston, who presented the discovery Friday at the American Association for the Advancement of Science conference in Boston.

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If confirmed, the find is yet another example of how microbes can survive in extremely punishing conditions on Earth.

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Though it was presented at a science conference and was the result of nine years of work, the findings haven't yet been published in a scientific journal and haven't been peer reviewed. Boston planned more genetic tests for the microbes she revived both in the lab and on site.

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The life forms40 different strains of microbes and even some virusesare so weird that their nearest relatives are still 10 percent different genetically. That makes their closest relative still pretty far away, about as far away as humans are from mushrooms, Boston said.

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Are you confident those microbes have a common ancestor with us? Go on Sure, and most of that stuff obviously shares a common ancestor. I was thinking about something novel that doesn't

I would say that it is as conclusive as it gets. The cincher for me is transfer RNA (tRNA). These are short RNA molecules that have an anti-codon that binds to mRNA and an amino acid attached to them. These are the molecules responsible for turning an RNA 3 base codon into a protein.There is simply no law requiring a strict correlation between an amino acid and the anti-codon of a tRNA. We see that the codon AUG results in a methionine in the protein, but there is no reason that an independent origin of life couldn't produce tRNA that uses AAG for methionine, or GGG.The universal nature of codon usage just screams universal common ancestry, at least to me. And I would bet all the money I have that they use the same sets of tRNAs that the rest of life uses.

Some years ago I read an article by a researcher pointing out that we may find that all life is clearly related because that is what we look for.We may not notice something truly different. Another bush of life just might be so different we don't see it as alive or just haven't noticed. It may have been crowded out into strange unlikely (to us ) niches.It doesn't seem all the likely to me either but it is an interesting thought.

A different set of tRNAs and codons would stick out like a sore thumb and couldn't be missed by biologists. Usage of different amino acids would also be an indication of a separate origin of life, and that would be obvious as well. A separate origin of life could also produce a very different genetic molecule that differs from DNA.What we should see with different origins of life is fundamental differences in genetic systems, and it just isn't there.

I remember reading that as well. I seem to remember that the author was calling for biologists to think about it and tailor observations in their specialty to look for "alien" life.I suspect that if other forms of organic (carbon-based) life arose on this planet that they were consumed before they could become widely established or they were just out-competed over the several billion years when the only life was single celled.The only places we are likely to discover "alien" life is in extreme habitats where there are only a few life forms adapted to the harshest conditions.I think it is interesting that the chloroplast organelles we see in modern plants probably started out as free living cyanobacteria that somehow became adapted to life inside plant cells. I read that mitochondria may have become part of almost all eukaryotic cells the same way.

You can call antibiotic resistance and example of "evolution" if you like, but I fail to see how it can be used as evidence to support the theory that all life evolved from a common ancestor.In order for all life to have evolved from a common ancestor, mutations must produce limitless increases in the information stored in DNA. But genetics science cannot demonstrate that mutations produce limitless increases in the information stored in DNA. The mutations seen in bacteria are like a merry-go-round ... they are constantly in motion but they don't actually go anywhere.

No.

Well, if we didn't see small-scale evolution, then we would have an excellent reason to doubt large-scale evolution. So the fact that we do see small-scale evolution is at least suggestive. No, just the increases that must have taken place to get us where we are now. That would be something you made up.

Translation: it IS an example of evolution. Well it's a single example of an organism mutating and adapting - it's not meant to support the entire edifice of common descent. For that we have mountains of evidence from the fossil record, taxonomy showing nested hierarchies, molecular genetics showing the inter-relatedness of species and the evolutionary process intself demonstrating how it came about - one small example being the evolution of anti-biotic resistence in bacteria. You just made an unsupported assertion - it's not necessary for DNA to be unlimited. And you used the 'I' word. This daft information argument has been shown to be wrong so many times it's just tedious. If you want to argue it, go to one of the many threads that do it. I wish you luck. Where do you expect them to 'go'? They're bacteria doing what bacteria do. To use the expression 'they're still bacteria.'Edited by Tangle, : No reason given.