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Epigenetics - Lamarckism? (Life Sciences)
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Komorikid


In: Gold Coast, Australia
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But there is a way of judging between models. The simplest wins. This is the advantage Darwin has over Lamarck. Darwin requires no thinking mechanism to guide changes. This advantage holds only so long as the simpler model fits the data.

Neo-Darwinism posits that all mutations are random and require no environmental input. The new mutated form then migrates to an environment that suits the mutation.Lamarckism posits that mutation occurs only when a changed environment requires it.

The second posit seem to be not only the simplest but also is born out by the data.

According to all the human genetic studies done in recent years random mutations in humans happen aprox every 5-10,000 years. Thus there have been 5-8 mutations in the Europe/Middle East gene pool in the last 50,000 years. This is the benchmark according to the experts.

Well the aborigines in Australia have been round for the same length of time yet show none of these mutations. On a biological level there is a species of ancient pine which goes back millions of years in the fossil record -- the Woolamai pine. It is the oldest extant living organism on the planet. The only know place where it exists is in an inaccessible valley west of Sydney. Of the one hundred or so individual trees that have been studied every single one has exactly the same DNA. The trees have remained undisturbed for millennia and not one random mutation is present not even in the dead ones.
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Ishmael


In: Toronto
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DPCrisp wrote:
The simplest wins.

Yes, this is telling: "wins" points to the fact that it's a game people play rather than some fabric of the universe. How do you answer someone who rejects Occam's Razor?

Ok. This is way too deep even for me. Applied Epistemology (AE) may be a branch of the philosophy of science but it begins with the essentials of the scientific method taken as a premise.

To answer your question as best I can however, I would say that probability has been observationally shown to increase in other cases (and mathematically, must be so) as the number of variables are reduced.

As for the God position, any solution that begins with God must also end there. Furthermore, human experience demonstrates that every action has a demonstrable immediate cause, though God may be some ultimate cause. The investigation of immediate causes is the purpose of science.

If God truly did breathe the breath of life into Adam then science will at least wish to bottle an air sample and subject it to chemical analysis.

This advantage holds only so long as the simpler model fits the data.

Yes, we know the rules and we are playing along, but let's not pretend we have to.

We must, so long as we intend to engage in a scientific investigation. Let's not get all existential.

Applied Epistemology explicitly seeks to penetrate the edifice and find whether the foundations really are agreed principles.

I'm not sure we go that deep.

We can argue that academics contradict their own principles or that one principle is overridden by something more fundamental, but unless we are on common ground, our arguments make no impact. Common ground runs out and we would do well to know where: the self-evidently-true is our bread-and-butter.

For common ground, appeal to Hume.

We can only delve into evolution where evolution is assumed. If someone else doesn't believe the phenomenon even exists, we have nothing to say to each other.

I completely disagee! Theoretically, it is possible to adhere to the scientific method and conclude that life has always been as it is now -- without beginning or end -- and that the presence or absence of any life form on one planet or another is engineered by an immediate cause other than mutation in existing life forms.
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Ishmael


In: Toronto
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Dan wrote:
Darwin requires no thinking mechanism to guide changes.

I didn't think Lamarck does either.

Yes. Lamarkism requires a "thinking mechanism". Some agent must have a capacity to take stock of the environment and respond.

I do not mean a conscious agent of course. A bacterium, in this sense, is a "thinking mechanism", if it engineers genetic change in "offspring" to suit the environment.

(BTW -- the notion that asexual, single-celled organisms can constitute individual species -- or that they have "offspring" -- I believe, is the origin of all our confusion. Correcting this misunderstanding, I suspect, is the key to a new model of evolution).
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DPCrisp


In: Bedfordshire
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The trees have remained undisturbed for millennia and not one random mutation is present not even in the dead ones.

So one tiny branch of the family survives. How old are the individuals? What can we say about the genetic diversity of the fossil specimens?
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DPCrisp


In: Bedfordshire
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Applied Epistemology (AE) may be a branch of the philosophy of science but it begins with the essentials of the scientific method taken as a premise.

Yes, that's a fair paraphrase of what I said.

As for the God position, any solution that begins with God must also end there.

That's it in a nutshell. But that's how some people like to play.

The investigation of immediate causes is the purpose of science.

Fair enough. But can science be done? Should we try...?

We must, so long as we intend to engage in a scientific investigation.

Exactly: we must, so long as...

I'm not sure we go that deep.

Well, Mick describes it in the video as taking a subject apart to see how it's made and either putting it back together again or throwing it out.

For common ground, appeal to Hume.

I was talking about what we actually do. Who appeals to Hume?

I completely disagree! Theoretically, it is possible to adhere to the scientific method and conclude that life has always been as it is now -- without beginning or end -- and that the presence or absence of any life form on one planet or another is engineered by an immediate cause other than mutation in existing life forms.

No, that is disagreeing in a limited sense. And a study of evolution leading to the conclusion that evolution does not take place still starts from the premise that it does. There is still the contrary position that it does not happen and science can not lead to the truth of the matter. There is no way to argue against that.

Yes. Lamarkism requires a "thinking mechanism". Some agent must have a capacity to take stock of the environment and respond.

I was going by NSOED: "his theory of organic evolution, which he ascribed to heritable modifications produced in the individual by habit, instinctive propensity, and the direct action of the environment." Nothing about "deciding what to do" there.

A bacterium, in this sense, is a "thinking mechanism", if it engineers genetic change in "offspring" to suit the environment.

That's a very queer sense of "thinking".

Doesn't producing random variation that then pruning out the unsuitable ones count as engineering genetic change in offspring to suit the environment... just as well as releasing spawn and milt succeeds in procreating giant clams, for all its haphazardry?

Does either Darwinism or Lamarckism require the mechanisms to operate within the individual?
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Mick Harper
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In: London
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Your statistics, Komoro, rather bear out orthodoxy. Since mutations occur randomly in the individual, it follows that the number of individuals will dictate the number of mutations. If

there have been 5-8 mutations in the Europe/Middle East gene pool in the last 50,000 years

then for the minute Aboriginal population over the same period the number would be about nought, and for the even tiddlier population of Woolamai pine, it ought to be nought per several million years.
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Mick Harper
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Applied Epistemology explicitly seeks to penetrate the edifice and find whether the foundations really are agreed principles.

I'm not sure we go that deep.

...er...yes, we do. In fact that's supposed to be the whole purpose of AE. It sprang, if you recall, from Kuhn's Structure of Scientific Revolutions ie that paradigms tend to be both false and long-lasting.
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Komorikid


In: Gold Coast, Australia
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Since mutations occur randomly in the individual, it follows that the number of individuals will dictate the number of mutations.

No this is not correct. It is an ASSUMPTION that mutations happen randomly and that they happen at random intervals.
All we know is that a mutation has happened. And that several have happened over the course of time. Neo-Darwinism dictates that they are RANDOM when there is no quantifiable evidence that this is so.
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Mick Harper
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I was neither agreeing nor disagreeing with the basic assumption (as it happens I disagree). Just pointing out your own examples didn't add up to anything by way of refutation since they believe in randomness so we can use probability theory. But by all means come up with some examples that do skewer clock-ticking neo-Darwinism. That would be immensely useful.
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DPCrisp


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Neo-Darwinism dictates that they are RANDOM when there is no quantifiable evidence that this is so.

They have no choice but to assert it is random in the absence of a theory (and some evidence) of non-randomness.

Being open to non-randomness is not the same as being able to deny randomness.

But how about this: organisms appear to have no direct or indirect control over their genes (i.e. mutations must be random), since they employ epigenetics to control their expression. If they could tweak the basic sequences, they would.

It makes sense that there should be a lower level of the system that can not be controlled, because the higher levels that do control things have to have a system, a reliable, deterministic way of doing things. It also makes sense that mutations should occur randomly as copy errors. And when they do, they might well throw the existing epigenetic set-up into disarray, too: it'd take time for new controls to "be developed", whatever that means.

So the question is: is neo-Darwinism enough? Can there be... does there have to be... something else? Does random mutation explain the punctuated part and epigenetics the equilibrium part?

After all, divergence and convergence are both changes.
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Rocky



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Someone says that maybe Scottish red hair evolved because of the bad weather:

http://www.dailymail.co.uk/news/article-1256269/Emily-
Pritchard-Scotlands-weather-ginger-hair-linked-says-genetics-student.html

Scotland's notoriously dreadful weather and the fact so many of its countrymen have ginger hair could be linked, a genetics student has claimed.

People with red hair and fair complexions are more likely to survive in areas where the summers are short and cool and the winter nights are long, Emily Pritchard said.

The 26-year-old came up with the theory, 'genetic mutation + bad weather = red heads', in an article about her sister's red hair for a University of Edinburgh magazine.


The article is mostly orthodoxy, but it makes me wonder if red hair was more common a long, long time ago. Maybe the first human tribe was red and/or blond haired with blue and green eyes and fair skin, and the dominant brown hair/skin/eyes genes came later. But then, I think this would mean that people arrived in Beringia after having lost the "caucasian" genes.

Imagine if Scotland were the cradle of civilization. I wonder where the shallow parts of the North Sea are.

Fomenko's already debunked the Vikings, so Scots don't need to get their red hair from them.
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Rocky



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Is there any skeletal evidence of the Neanderthals in Britain? It seems not:

The first Neanderthal specimen was recognised in the Neander Valley, outside Dusseldorf, Germany, hence the name. We have known for a long time that Neanderthals reached Britain but new evidence about their reign here is emerging all the time.

A jawbone, thought to be at least 31,000 years old and excavated from Kent's Cavern in Torquay in 1926, is being reassessed by an international team who believe that advances in analytical methods may help establish if it is more ancient than was first thought and is perhaps Neanderthal.

"If it does turn out to be Neanderthal, this would be the first proper mainland late Neanderthal from Britain," says Prof Chris Stringer, of the Natural History Museum, one of the research team and author of Homo Britannicus: The Incredible Story of Human Life in Britain.


http://www.telegraph.co.uk/science/science-
news/3302028/Were-Neanderthals-our-enemies-or-lovers.html

Maybe modern humans evolved in Scotland, and then they populated the continent. As they populated the continent, they killed off the Neanderthals because they'd never encounted them in Britain and were scared of them.
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Mick Harper
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Look, 'Scotland' was covered by a several thousand feet thick ice sheet until c 12,000 BC so how could anything have evolved there during this time frame?

As I have pointed out ad nauseam, ice sheets destroy all recent fossils so it follows that all Neanderthal (and other hominid and early modern human) evidence will be found 'around Torquay' or similar places south of the Thames Valley, irrespective of what was actually happening further north during earlier epochs.
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Ishmael


In: Toronto
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Rocky wrote:
Fomenko's already debunked the Vikings, so Scots don't need to get their red hair from them.


Have you finished Book III? I haven't yet got that far.
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Rocky



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Mick Harper wrote:
Look, 'Scotland' was covered by a several thousand feet thick ice sheet until c 12,000 BC so how could anything have evolved there during this time frame?


Sorry, forgot about that. Here's the map:
http://www.theresilientearth.com/files/images/tahiti_ice_cover.jpg

But not all of Britain/Ireland was glaciated. They still haven't found anything neanderthal in the unglaciated parts.

The Red Lady of Paviland is a modern human male skeleton from Wales. The skeleton apparently dates to c.29,000 before present.
http://www.channel4.com/news/articles/science_technology/red
+lady+skeleton+29000+years+old/979762

Do the Welsh have red hair? Are they considered to be fierce?

Oh yeah, here's a picture of London(?) during the last ice age:
http://i.dailymail.co.uk/i/pix/2010/01/09/article-0-
032F8F20000005DC-103_468x291.jpg
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