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So, Lamarck was right after all. Do we owe him an apology?


Michaelangelica

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An Apology in this special anniversary year of Darwin's and his theory of Natural Selection?

 

From a brave biologist:-

Robyn Williams(interviewer/journalist): I was told way back that this is precisely what couldn't work anymore because that's Lamarckism and Lamarck suggesting that you adapt your inheritance by your experience. In other words, the old giraffe stretching up to high branches getting longer necks and they pass it on to their little offspring. And that's precisely what was not supposed to happen. Are you saying that they've changed the rules?

 

Jane Mellor(biologist): Darwin still plays a pretty major role, and you can do experiments to show that Darwin was right and mutations in DNA, changes in the genetic information, pre-exist the selective pressure on which they're selected for.

But Lamarck also was right and we know that the epigenetic code, which is changes not encoded in mutations in the DNA, can have a major influence. And yes, we can select for individuals based on epigenetic characteristics which can make them fitter.

. . .

. . .

. . .

Robyn Williams: So we've got essentially our code which is, if you like, the perfection of zillions of years that we inherit, and then we've got the adaptability, recognising what the outside is like, so that we can suit it. So we've got these two influences. When it comes to epigenetics, which is quite a young field, it's obviously amazingly exciting. How big is it actually?

 

Jane Mellor: Oh it's huge. You've probably heard of the human genome project, and that was many, many, many man-years and a large number of dollars. We're now trying to understand the epigenetic code of the human genome, and this will involve understanding not just the sequence of the base pairs in the DNA but the code of the modifications which wrap around the DNA, and these vary in every cell in every different developmental state in the human body. So the challenge is absolutely immense, but it's the only way we're really going to understand how our genomes work, is by complimenting the genetic code with the epigenetic code.

 

So there are huge projects in Japan, in America and in Europe, epigenome initiatives to try and understand the code. And we now have fantastic facilities, we have the deep sequencing technology which makes this now much, much more feasible. So maybe in ten years time we can talk about the human epigenetic code and we can begin to understand how an individual cell from being a fertilised egg undergoes no genetic changes but lots and lots of epigenetic changes which bring about the necessary changes in the cells to a fully functioning human being.

 

Robyn Williams: Okay, so what's the payoff when you've cracked it in ten or five years time?

 

Jane Mellor: Well, it probably won't be five years or ten years time! No, I think obviously the payoff is going to be not only just fundamental understanding in terms of what a eukaryotic organism is but tools to tackle diseases like cancer which have primarily an epigenetic basis, and I think that has to be our long-term goal.

Epigenetics - Science Show - 7 February 2009

Full text available, and podcast available for 3 weeks

 

Jane Mellor

Lecturer Department of Biochemistry University of Oxford

Jane Mellor Research Group - Department of Biochemistry, University of Oxford

 

So if Great-Grandpa went to the Boar War, Grandpa went to WW1, Dad went to WW2 and I missed out on Vietnam; how does that effect and affect my genetic inheritance?

 

A good PhD thesis topic? How many years to they give you to complete a PhD?

Three score years and ten?:blahblahblah:

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Good read mate. :blahblahblah:

 

The take home point seems to be that cellular signaling can trigger genetic variance in the stem cell. At least, that's the impression I get from reading one of her abstracts.

 

Post-translational modifications to histone proteins and methylation of DNA comprise the epigenome of a cell. The epigenome, which changes through development, controls access to our genes. Recent advances in DNA sequencing technology has led to genome-wide distribution data for a limited number of histone modifications in mammalian stem cells and some differentiated lineages. These studies reveal predictive correlations between histone modifications, different classes of gene and chromosomal features. Moreover, this glimpse into our epigenome challenges current ideas about regulation of gene expression. Many genes in stem cells are poised for expression with initiated RNA polymerase II at the promoter. This state is maintained by an epigenetic mark through multiple lineages until the gene is expressed.

 

Epigenetics is not Lamarckian or anything other than regulatory factors in gene expression. Pyrotex did a great job of assessing the various definitions. In this case, epigenetics takes its typical biological definition of "expression regulation".

 

It's important to note that epigenetic artifacts are still subject to Natural Selection. :hihi:

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So, Lamarck was right after all. Do we owe him an apology?
Lamarck is owed, IMHO, lots of respect, as he was a truly pioneering scientist, arguable the father of modern biology. His general sense of biological evolution was correct, differing from the modern idea more in detail than in overall structure. His major rejected idea, the inheritance of acquired characteristics, has been the subject of so much attention, we tend to forget how much of modern biology continues to agree in principle if not in detail with his other ideas.

 

There’s a human psychological tendancy, I think, to cast people and ideas in black or white, completely wrong or completely right, terms. This tendency impedes and misguides scientific study and understanding, and should, I think, be diligently avoided.

So if Great-Grandpa went to the Boar War, Grandpa went to WW1, Dad went to WW2 and I missed out on Vietnam; how does that effect and affect my genetic inheritance?
According to everything I’ve read about epigenetic, it would most likely have to be you gandma or other maternal ancestors, she’d have to be pregnant with your or an ancestor, and the war would have to have some physiological affect, such as via changes to her diet or stress levels. There’s some basic research that indicates that suggests that epigenetic influences can “reprogram” germ line cells (Eg: sperm and egg cells), but a sense in most of what I’ve read that epigenetics are most significant during the development of an embryo and fetus.

 

The line between what we do and don’t call “epigenetics” can be vague. For example, if you take growth hormone drugs, they works by activating genes that cause you bones to grow longer, but few people would call this an example of epigenetics, perhaps because the therapeutic practice has been around longer than the term “epigenetics”.

 

I think a lot of confusion exists about memory and genetics. There’s strong evidence and speculation that the growth and change in brain cells involved in long term memory formation involves complicated alterations to the proteins coded in these cells’ DNA via RNA. There’s strong evidence and theory that immune system cells have their DNA meaningfully “reprogrammed” by the mechanism that, in most cells, repair damage to it, so that the various kinds of immune cells have significantly different DNA than one another. There are many similarities between immune cells and nerve cells, so very reasonable speculation that nerve cells also have such differences. However, there’s no known of reasonably speculated mechanisms that could actually store memories – for example, aversion to some hazard, recognition of a face, or a remembered telephone number – in DNA, so it appears nerve cell DNA and epigenetic factors don’t actually store memories, but give the cells the ability to store them.

 

There’s some discussion and references about the above at and around “DNA repair, recoding, immune cells, nerve cells, and inheritance”, and an example of what I consider confusion about epigenetics and memory formation in 18385.

 

Controversy about the heritability of memories is very old, predating even Lamarck (ca. 1800), and reaching something of a high, IMHO, in the 1960 and 70s, when psychologist James V. McConnell dedicated himself to supporting the idea that memories – specifically, the knowledge of how to negotiate a maze in a specific family of worms, panarians – can be transmitted by eating an animal with the memories. The idea had a serious problem, though, because other researchers were unable to independently reproduce McConnell’s findings, leading to a scientific consensus that they weren’t really happening. This was discussed in 1762.

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This was covered pretty well by John over at Evolving Thoughts, complete with references:

 

 

Evolving Thoughts: Myth 3: Darwin was a Lamarckian

Myth 3: Darwin was actually a Lamarckian

 

"But here's what Darwin did not think: that the variation itself was acquired from parental experience, which is what we typically think of as being Lamarckian. This is what Mayr termed soft inheritance. Darwin held that variation arose in ways that he did not understand but were likely to be explicable in natural terms, but which were not correlated to the present or future needs of the organisms, just as we do today. Any variant that was used was more strongly inherited, and he developed his ill-fated Pangenesis theory to account for that "fact", but this didn't make the variants occur or more likely. So in any meaningful sense, Darwin was no Lamarckian.

 

The very use of the term "Lamarckian", like the use of the contrasting term "Weismannian" (Griesemer 2005), is an act of battle. It raises a standard under which scientists and those fellow travellers like myself can rally against the enemy. To say that Darwin was a "Lamarckian" (especially when he was not in this regard) is a way of strengthening those who have, by their own account, refined Darwin and stripped him of error. Poor Darwin, who lacked the resources and data to know better! We have fixed his mistakes. On the other side, those who continually assert their heterodoxy by calling themselves "Lamarckian" (e.g., Jablonka and Lamb 1995, Steele, Lindley and Blanden 1998) seek to mark out their originality and again, claim to be fixing the mistakes of the past. Steele may be a Lamarckian in Weismann's (though I rather doubt in Lamarck's) terms, but Jablonka and Lamb are not. They are anti-Weismann, not anti-Darwin. " <
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I am not too familiar with the Lamarkian orientation, but it appears to be the angle I have been arguing. These modifications seem to be based on cause and effect. I went one step further, to see if I could explain a basis for the cause and affect, in a general way, that could apply to all cases, regardless of the wide array of mechanisms they will probably find. The best variables, I found, are centered on hydrogen bonding and water.

 

Where hydrogen bonding comes in, is what I call configurational potential. A particular epigenome is a type of unique DNA shape for any given DNA. The easiest analogy to see is an active protein and its denatured version. Only one shape is active, even though both are the same at the covalent level. In the case of DNA, the same genes, in different passive and active configurations, affect the differentiated activity. Different configurational shapes have an impact on the local water, which has an impact on the configurational shapes. This allows distant genes to impact other genes where there appears to be no direct physical connection. Genes don't have to be connected, directly, to affect the activity of other genes. The group configuration is acting like one thing.

 

Say you begin with a given covalent DNA. Its configurational shape, to define equilibrium, may involve bringing genes together that may not be adjacent on the DNA, if we look at only the covalent backbone. There may be an advantage to shifting the location of some of the genes within the covalent structure. If that is not possible, equilibrium may involve other mechanisms to change the potential of the grouping. Methylation of the DNA, reduces bases on DNA with a methyl group, because the configurational grouping is under potential to be reduced.

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As always Craig, an insightful post...

 

Lamarck is owed, IMHO, lots of respect, as he was a truly pioneering scientist, arguable the father of modern biology.

 

It's difficult to pin a "father", but no doubt, Lamarck was a great scientist. :shrug:

 

His general sense of biological evolution was correct, differing from the modern idea more in detail than in overall structure. His major rejected idea, the inheritance of acquired characteristics, has been the subject of so much attention, we tend to forget how much of modern biology continues to agree in principle if not in detail with his other ideas.

 

There’s a human psychological tendancy, I think, to cast people and ideas in black or white, completely wrong or completely right, terms. This tendency impedes and misguides scientific study and understanding, and should, I think, be diligently avoided.

 

Well said! Unfortunately, I fear I might be in the b/w camp here and this is a good call to arms. :)

 

According to everything I’ve read about epigenetic, it would most likely have to be you gandma or other maternal ancestors, she’d have to be pregnant with your or an ancestor, and the war would have to have some physiological affect, such as via changes to her diet or stress levels. There’s some basic research that indicates that suggests that epigenetic influences can “reprogram” germ line cells (Eg: sperm and egg cells), but a sense in most of what I’ve read that epigenetics are most significant during the development of an embryo and fetus.

Indeed.

 

The line between what we do and don’t call “epigenetics” can be vague. For example, if you take growth hormone drugs, they works by activating genes that cause you bones to grow longer, but few people would call this an example of epigenetics, perhaps because the therapeutic practice has been around longer than the term “epigenetics”.

I would add that it is not considered epigenetics because it does not affect the germ line.

I think a lot of confusion exists about memory and genetics. There’s strong evidence and speculation that the growth and change in brain cells involved in long term memory formation involves complicated alterations to the proteins coded in these cells’ DNA via RNA. There’s strong evidence and theory that immune system cells have their DNA meaningfully “reprogrammed” by the mechanism that, in most cells, repair damage to it, so that the various kinds of immune cells have significantly different DNA than one another. There are many similarities between immune cells and nerve cells, so very reasonable speculation that nerve cells also have such differences. However, there’s no known of reasonably speculated mechanisms that could actually store memories – for example, aversion to some hazard, recognition of a face, or a remembered telephone number – in DNA, so it appears nerve cell DNA and epigenetic factors don’t actually store memories, but give the cells the ability to store them.

I agree. Human long term memory is not analogous to a computer hard drive that selectively stores memory based on the user's request. Human memory, and indeed all known memory mechanisms, point to complex interactions that are not very well understood. Yet, we do know that memory is not directly transferred through DNA. Sorry Shamans. ;)

 

But I (we) digress...

Lamarckianism, and consequentially the related form of epigenetics, is dead, for now.

(well, it's not really dead, but you know what I mean) :D

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Simply because something looks like inheritance of acquired traits does not mean it is Lamarckism(in the sense intended by Lamarck), even though even some professional biologists mistakenly claim this(and I think they often do it to ruffle feathers and get media attention).

This paper by S J Gould from "The Panda's Thumb"(way back in 1988) explains quite clearly that Lamarckism was, more than anything else, about spontaneously generated lineages being driven up a ladder of progress by some mysterious internal complicating force. In fact, acquiring traits from the local environment actually often delayed or detoured the central process of Lamarck's evolution- the ascent of the ladder of progress:

 

Shades of Lamarck

The inheritance of acquired characters usually goes by the shorter, although historically inaccurate, name of Lamarckism. Jean Baptiste Lamarck (1744- 1829), the great French biologist and early evolutionist, believed in the inheritance of acquired characters, but it was not the centerpiece of his evolutionary theory and was certainly not original with him. Entire volumes have been written to trace its pre- Lamarckian pedigree (see Zirkle in bibliography). Lamarck argued that life is generated, continuously and spontaneously, in very simple form. It then climbs a ladder of complexity, motivated by a "force that tends incessantly to complicate organization." This force operates through the creative response of organisms to "felt needs." But life cannot be organized as a ladder because the upward path is often diverted by requirements of local environments; thus, giraffes acquire long necks and wading birds webbed feet, while moles and cave fishes lose their eyes. Inheritance of acquired characters does play an important part in this scheme, but not the central role. It is the mechanism for assuring that offspring benefit from their parents' efforts, but it does not propel evolution up the ladder.

 

In the late nineteenth century, many evolutionists sought an alternative to Darwin's theory of natural selection. They reread Lamarck, cast aside the guts of it (continuous generation and complicating forces), and elevated one aspect of the mechanics-- inheritance of acquired characters--to a central focus it never had for Lamarck himself. Moreover many of these self- styled "neo-Lamarckians" abandoned Lamarck's cardinal idea that evolution is an active, creative response by organisms to their felt needs. They preserved the inheritance of acquired characters but viewed the acquisitions as direct impositions by impressing environments upon passive organisms.

 

Although I will bow to contemporary usage and define Lamarckism as the notion that organisms evolve by acquiring adaptive characters and passing them on to offspring in the form of altered genetic information, I do wish to record how poorly this name honors a very fine scientist who died 15O years ago. Subtlety and richness are so often degraded in our world. Consider the poor marshmallow--the plant, that is. Its roots once made a fine candy; now its name adheres to that miserable ersatz of sugar, gelatine, and corn syrup .

 

So do we owe Lamarck an apology? Yes, but not for what is implied in the first post of this thread. Lamarck deserves an apology for our ignorance of his theory, and the labeling of any phenomenon that superficially resembles his ideas as being Lamarckian!

 

 

Now, regarding soft-inheritance, or instances of epigenetic inheritance that survive meiosis(as opposed to epigenetic inheritance through mitosis in cell lineages, which is a kind of phenotypic plasticity), there are some cases of this on record. I've tried to paraphrase this a bunch of times, but I just can't get it out right, so here is Eric J. Richards commenting in an article in Nature:

Access to articles : Nature Reviews Genetics

There is no reason on mechanistic grounds to reject the possibility that environmentally induced or modified epialleles can be inherited. It might be more meaningful to ask why we are not constantly confronted with the inheritance of environmentally induced phenotypic variation. In the case of mammals, the answer probably lies in a reasonably comprehensive erasure of epigenetic marks and the early germ–soma divergence that ensures that epigenetic alterations in somatic lineages are not transmitted through the germ line. The germ–soma division formed the core of Weismann's rejection in the late nineteenth century of neo-Lamarckian inheritance. These considerations indicate that epigenetic inheritance is unlikely to mediate in mammals the most extreme form of soft inheritance that involves the transmission of adaptive acquired characters (Box 4). However, a less extreme form of soft inheritance is possible that might be based on the transmission of environmentally induced or influenced epialleles that are generated in the germ line. In this case, there is no reason to propose that these epialleles will have any adaptive significance, without resorting to the contortion of invoking a parallel induction of epigenetic changes in reproductive and somatic lineages. However, in organisms in which reproductive lineages or germ lines are derived from vegetative or somatic lineages late in development and epiallele erasure is less extensive, such as plants, both forms of soft inheritance could operate through epigenetic mechanisms.

 

So, out of the handful of cases of soft-inheritance on record, the majority of them are in plants, and for the reasons outlined above involving the relation of somatic and germline cells in plants vs animals. He also points out that unless we assume(there is no reason to do so) parallel inheritance between somatic and germ-line cells in mammals, then any epigenetic changes in germ-line cells won't be adaptive anyway(how could they possibly be relevant to the environment?).

Richards goes on to discuss the implications of these findings for theory:

Access to articles : Nature Reviews Genetics

Even if it is conceded that the molecular mechanisms are present to mediate soft inheritance through epigenetic mechanisms, the significance of such mechanisms must be questioned. The variation that has been shown to underlie the developmental and phenotypic differences between species occurs at the genetic rather than the epigenetic level.

 

What he is saying is that epigenetic change is dependent on underlying genetic variation anyway. On top of this, as Freeztar noted in a previous post above, all of these changes are still subject to natural selection, and Darwinian, not Lamarckian in nature.

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Did everyone listen to or read the link i gave?

we can begin to dissect the language of epigenetics and understand how a signal coming outside of a cell actually results in either an increase or a decrease in the expression of a gene.

 

Robyn Williams: So when it's coming from outside, a bit like those meteorites from outer space hitting the Earth...so something coming from outside to this little yeast bug. What sort of thing is it and what part of the genome does it affect?

 

Jane Mellor: Yeast, because they're free living organisms, they normally live on the skin of grapes or on leaves, they're most influenced by things like UV radiation, by the availability of nutrients and the type of nutrients that are available, so the sort of things that also affects us. And the nutrients will signal to receptors on the cell and they will set up signal transduction cascades which move signals from the outside of the cell right into the nucleus where the DNA is, and it's those signals that can influence the epigenetic code. Most of them seem to influence the enzymes that write the epigenetic code and can have very dramatic influences on their capacity to function. So it really is going from outside the cell to right into the heart of the cell.

 

Robyn Williams: Dramatic and lots of it happening?

 

Jane Mellor: Very dramatic, yes. One of the pathways we've just defined shows how when cells are starved for nutrients, particularly glucose which most cells love to grow on, it causes a very dramatic disintegration of one of the major writers of the code, a wonderfully named complex called SAGA, so we're writing the code of SAGA, if you like, and this complex writes a very important modification and this affects very dramatically how a whole wide group of genes are expressed.

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Did everyone listen to or read the link I gave?
I did. Like most of the abc.net.au interviews you post, I found it easy to understand and informative.

 

From the subtext of you message, though, I get the impression you think we’re all missing an important point. I don’t think we are.

 

A key point, which I suspect you may be missing, is that our growing understanding of the importance and mechanics of epigenetics is not the same thing as growing acceptance of Lamarck’s old idea of the inheritance of acquired traits, oft termed Lamarckism. Lamarchism holds that experiences – eg: strong arm and back muscles from a lifetime of ditch digging, or strong, fast legs from a lifetime of rickshaw pulling, or possibly even something as abstract as knowing that a snake with an even number of stripes is good eating, while one that looks like it but has an odd number of stripes is aggressive and deadly poisonous, can be passed to our descendents purely without any social contact whatever. Epigenetics holds, in short, that there’s more to biology than just the genome coded in our DNA.

 

Though the word is new-ish, the idea of Epigenetics is older than the discovery of DNA in the 1950s. For example, we’ve long known that certain substances, such as hormones, control the development and workings of cells and tissues, and that chemically similar substances made artificially or in other plants and animals could have a similar effect. The present-day study of epigientics, as I understand it, is simply increasing the depth of our knowledge of these phenomena, and revealing them to be vitally intertwined with the direct expression of genes in DNA and RNA. In the process, it’s also rather dashing the hopes of “bioinfomaticians” (a category that arguably includes me) that, now that we’re able to quickly and inexpensively determine complete individual genomes, with a bit of computing power and ingenuity, we’d quickly understand everything about biology. Epigenetics can be synonymous with “it’s not going to be that easy, suckers!” ;)

 

The whole complicated subject gets philosophically complicated when considered deeply enough. Most of the molecules involved in epigenetic processes are, in some fashion, coded for in genes in DNA, even if not the DNA of the cell or even the organism being affected, so, in a sense, most of epigenetics is still “in the DNA”. On the other hand, even the simplest cell appears not to be able to function without a lot of “outside” epigenetic prodding and control, so one can argue that epigentics is central to biology, genetics just a useful feature at its disposal.

 

What is fairly certain in all this is that far-out Lamarckian ideas, such as that if I memorize and recite “If” by Rudyard Kipling enough prior to his conception, my child will be born knowing the poem, are wrong. The possibility that some sort of “acquired trait” can be passed between generations, however, can’t be entirely ruled out.

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If you look at the range of new physical disorders that are spreading in culture, such as obesity, attention and hyperactivity disorders, these are occurring faster than can be explained with reproductive transmission from a common genetic point of origin, yet they are attributed to genetics. There was not one person who began it and bred it into the general population. Rather it is occurring independently of breeding but is still being traced back to genetics. They all have a connection to behavior or the brain and are often cultural dependent. Does this have selective advantage, since it is spreading? Or can genetic changes have nothing to do with selective advantage in an objective sense of Darwinian evolution, but could it have a subjective connection, that alters the genes.

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If you look at the range of new physical disorders that are spreading in culture, such as obesity, attention and hyperactivity disorders, these are occurring faster than can be explained with reproductive transmission from a common genetic point of origin, yet they are attributed to genetics.
HBond, can you back this claim up with a link or reference, as required by the site rules? I believe you are confusing information about the occurrence of these conditions, which is not believed heritable, with predisposition for them, which is.

 

Taking the first of the 3 examples given, obesity is normally defined as having a body mass index greater than [math]30 \,\mbox{kg/m}^2[/math], vs. a normal BBI of 18.5 to 25. People with BMIs between 25 and 30 are normally termed “overweight”. Except for people with rare metabolic disorders, such a BMI cannot occur unless the person eats too much and/or exercises too little.

 

Predisposition to overeating and under-exercising are believed, with considerable scientific support, to be heritable. Actually engaging in these behaviors and becoming overweight or obese, is not.

 

Public health experts consider a “global epidemic of obesity” to have occurred in the last 25 to 50 years, with the incidence of obesity in wealthy nations more than doubling in the last 25 years. However, this increase is occurring in both old and young, so can’t be attributed to heritability.

 

The increase in obesity is almost certainly due to social and economic factors, primarily the increased availability of food and decreases in normal activity due to increasingly mechanized transportation and labor-saving machines.

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I agree with the external source of the affect and the connection to behavior. It would be interesting to follow this trend and see if it creates a greater occurrence of predisposition that begins right at birth or childhood. Or kids eat more earlier.

 

But another way to look at it is, losing the weight is not easy since the inertia of behavior or habit, becomes also almost like an instinct, due to the social adaptation. If you had animals, forming a collective learned habit, due to environment, one might attribute that to genetics. But it could be due to animal socio-economics or what adapts the group to their environment and is initially copied. If it ends up as genetics, this is important to cause and affect. Ending up in genetic means less effort to do the same thing, since they do, naturally, even if the social environment changed. The data above would tell us if the group instinct-habit is becoming more second nature or genetic.

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Thanks everybody, very interesting reads from all, especially Craig.

As you may have guessed by now I am a frustrated biologist with no formal training in the area

 

On memory and worms. I can't quite see the link.:)

I searched the web and the original experiment has been replicated several times especially/mostly in the 60s, with similar results.

five articles here eg

Planaria which have cannibalized untrained planaria exposed to photic stimuli only, handling only, or previous conditioning, all require significantly fewer trials in a conditioning situation than naive planaria.

Planaria: Memory Transfer through Cannibalism Reexamined -- Hartry et al. 146 (3641): 274 -- Science

and

Somatic Inheritance of Habituation of Responses to Light in Planarians -- Westerman 140 (3567): 676 -- Science

 

also from pub med

PLANARIA: MEMORY TRANSFER THROUGH CANNIBALISM REEXAMINED.

KARTRY AL, KEITH-LEE P, MORTON WD.

 

Planaria which have cannibalized(sic) untrained planaria exposed to photic stimuli only, handling only, or previous conditioning, all require significantly fewer trials in a conditioning situation than naive planaria.

 

The most recent article 2003 I can't get at. it may thow some light on this

RNA and Memory: From Feeding to Localization

 

Ralph J. Greenspan

 

The Neurosciences Institute, 10640 John Jay Hopkins Drive, San Diego, CA 92121, USA

 

Summary

 

Ideas about the role of RNA in learning and memory have a checkered past. A new study in Drosophila, synthesizing classical forward genetics with DNA microarrays, brings us closer to seeing that role clearly.

Current Biology - RNA and Memory: From Feeding to Localization

Found summary here

ScienceDirect - Current Biology : RNA and Memory: From Feeding to Localization

I don't think it helps?:confused:

 

Jung talked of "racial memory" and a "collective unconscious" in man.

He is one early Psychologist on my "study one day list". The best i have done so far is read a huge tomb on symbols in art. (many years ago).

Racial Memory

 

Psychology Proposed by the Swiss psychiatrist Carl Gustav Jung (1875–1961).

 

Most often associated with Jung’s analytic psychology, racial memory consists of thoughts, feelings and inferences which are believed to be passed on from generation to generation and which influence the behaviour of the individual.

According to Jung racial memory is a part of the COLLECTIVE UNCONSCIOUS. Freud also believed in racial memory, but focused on a different aspect of it. The idea of racial memory is highly speculative.

 

C G Jung, Analytical Psychology: Its Theory and Practice (New York, 1968)

Racial Memory

Wouldn't some animals and insects have this? We call it instinct?

 

i see Lamrak has been miss-represented and falsely accused and pigeon holed.

 

I am not confident that I see the error of my ways however (still thinking). I think I am wrong, but haven't got my head around it yet so don't get cranky Craig ) not that you ever do-the patience of a saint)

 

some other stuff of interest

Why Are Some People More Susceptible To Depression Than Others? Stressed-out Mice Reveal Role Of Epigenetics In Behavior

"It's a way for a cell to have a sort of memory," explains Trono.

Why Are Some People More Susceptible To Depression Than Others? Stressed-out Mice Reveal Role Of Epigenetics In Behavior

Epigenetics: Plants Display 'Molecular Amnesia'

They have demonstrated for the first time the reversal of what is called epigenetic silencing in plants.

. . .

epigenetic modifications can be passed on from parent cell to daughter cell, ensuring each cell line has the proper characteristics consistently over many generations.

. . .

One kind of gene is quite distinct from all of the others, because it is nearly always epigenetically inactivated. These are the genes carried by transposons, or "jumping genes."

. . .

"This may relate to the degree to which a given gene or group of genes must be reprogrammed each generation," Singh said. "We can now use transposons to probe for variations in the epigenetic landscape of the maize genome. It may turn out that forgetting can be as important as remembering. Our findings suggest that erasure of heritable information may be an important component of epigenetic machinery."

Epigenetics: Plants Display 'Molecular Amnesia'

 

Rethinking The Genetic Theory Of Inheritance: Heritability May Not Be Limited To DNA (twin studies)

The epigenetic heritability may help explain currently unclear issues in human disease, such as the presence of a disease in only one monozygotic twin, the different susceptibility of males (e.g. to autism) and females (e.g. to lupus), significant fluctuations in the course of a disease (e.g. bipolar disorder, inflammatory bowel disease, multiple sclerosis), among numerous others.

 

And

just something interesting that has nothing to do with this ( i think?)

Whenever humans create a new antibiotic, deadly bacteria can counter it by turning into new, indestructible super-bugs.

That's why bacterial infection is the number one killer in hospitals today.

But new research from Tel Aviv University may give drug developers the upper hand in outsmarting bacteria once and for all.

 

The secret weapon against a colony of bacteria may be to stress it with its own protection system, which forces it to reduce its population through cannibalism.

 

"Our studies suggest this is a new way to fight off bacteria," says Prof. Eshel Ben-Jacob, an award-winning scientist from Tel Aviv University's School of Physics and Astronomy.

"If we expose the entire colony to the very same chemical signals that the bacteria produce to fend off competition, they'll do the work for us and kill each other.

This strategy seems very promising -- it's highly unlikely that the bacteria will develop resistance to a compound that they themselves produce."

Can cannibalism fight infections?

Whew that's me done.

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As you may have guessed by now I am a frustrated biologist with no formal training in the area.

 

Welcome to the club!

 

Jung talked of "racial memory" and a "collective unconscious" in man.

He is one early Psychologist on my "study one day list". The best i have done so far is read a huge tomb on symbols in art. (many years ago).

 

Racial Memory

 

Psychology Proposed by the Swiss psychiatrist Carl Gustav Jung (1875–1961).

 

Most often associated with Jung’s analytic psychology, racial memory consists of thoughts, feelings and inferences which are believed to be passed on from generation to generation and which influence the behaviour of the individual.

According to Jung racial memory is a part of the COLLECTIVE UNCONSCIOUS. Freud also believed in racial memory, but focused on a different aspect of it. The idea of racial memory is highly speculative.

 

C G Jung, Analytical Psychology: Its Theory and Practice (New York, 1968)

 

Racial Memory

Wouldn't some animals and insects have this? We call it instinct?

 

This sort of thing really makes me wonder.

Where does instinct end and rational thought or "reasoning" begin?

 

The other day, while I was at work,

I noticed a rather large garden spider building it's web.

That web was an engineering marvel to say the least!

A perfect "circle within a circle" configuration held together by

perfectly spaced "rays" from the center to the outer perimeter,

and...get this...suspended in the air exactly half way

between two trees twelve feet, eight inches apart!

(I measured it as carefully as I could using a tape measure,

but since the web was also about twelve feet in the air,

I may be off by a few inches or so.

Anyway, I wasn't about to go get a ladder, because the folks I work with

would then have thought that I had really lost my mind!)

 

We get garden spiders here every spring and summer

and I have seen plenty of webs, but this one was simply astonishing!

Truly, this was the "Michaelangelo of spiders"!

I wanted to congratulate it and shake its "hand"!

 

I was wondering...how on God's green earth did it do that?

If you and I were that size, we couldn't even dream

of accomplishing such a feat for it would probably take us several years

just to secure the initial thread from one tree to the other!

 

Instinct? Intelligence? Is there a difference? I wonder!

 

How did it "know" the "halfway point" between the two trees?

Did it "count it's steps" and divide by two?

Did it "eyeball" the distance? Estimate?

Or perhaps it knew by somehow gauging how far

it's weight caused the initial thread to bend.

A natural sense of trigonometry?

Or maybe it was just luck.

 

The thing is, all the webs here are

roughly halfway between two trees whose distances vary,

so there must be some kind of intelligence at work here.

 

I could go on and on with other questions such as:

How did it know it's initial thread was strong enough

to hold its weight at that distance?

Indeed, how did it get it's initial thread from one tree to the other?

(Spiders can't fly or jump that far and the ground below

was filled with grass, weeds, rocks and dead leaves,

so as to make it very difficult to avoid getting it entangled.)

 

And why did the talents of this particular garden spider,

far exeed those of it's peers?

 

If "instinct" is analagous to "programming",

and "intelligence" to "creativity",

then there were certainly elements of both in that particular spider.

It had "soul"!

 

Don.

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Welcome to the club!

 

 

 

This sort of thing really makes me wonder.

Where does instinct end and rational thought or "reasoning" begin?

 

The other day, while I was at work,

I noticed a rather large garden spider building it's web.

That web was an engineering marvel to say the least!

A perfect "circle within a circle" configuration held together by

perfectly spaced "rays" from the center to the outer perimeter,

and...get this...suspended in the air exactly half way

between two trees twelve feet, eight inches apart!

(I measured it as carefully as I could using a tape measure,

but since the web was also about twelve feet in the air,

I may be off by a few inches or so.

Anyway, I wasn't about to go get a ladder, because the folks I work with

would then have thought that I had really lost my mind!)

 

We get garden spiders here every spring and summer

and I have seen plenty of webs, but this one was simply astonishing!

Truly, this was the "Michaelangelo of spiders"!

I wanted to congratulate it and shake its "hand"!

 

I was wondering...how on God's green earth did it do that?

If you and I were that size, we couldn't even dream

of accomplishing such a feat for it would probably take us several years

just to secure the initial thread from one tree to the other!

 

Instinct? Intelligence? Is there a difference? I wonder!

 

How did it "know" the "halfway point" between the two trees?

Did it "count it's steps" and divide by two?

Did it "eyeball" the distance? Estimate?

Or perhaps it knew by somehow gauging how far

it's weight caused the initial thread to bend.

A natural sense of trigonometry?

Or maybe it was just luck.

 

The thing is, all the webs here are

roughly halfway between two trees whose distances vary,

so there must be some kind of intelligence at work here.

 

I could go on and on with other questions such as:

How did it know it's initial thread was strong enough

to hold its weight at that distance?

Indeed, how did it get it's initial thread from one tree to the other?

(Spiders can't fly or jump that far and the ground below

was filled with grass, weeds, rocks and dead leaves,

so as to make it very difficult to avoid getting it entangled.)

 

And why did the talents of this particular garden spider,

far exeed those of it's peers?

 

If "instinct" is analagous to "programming",

and "intelligence" to "creativity",

then there were certainly elements of both in that particular spider.

It had "soul"!

 

Don.

 

I have seen webs like you describe. It's important to note that spiders can "sling" or "throw" their silk quite a distance. This enables them to build webs mid-air without ever touching the ground.

 

Is it intelligence? I don't think so. Is it instinct? Probably.

A factor to consider is physical constraints. If the spider built its web to the left of center, weight would dictate a different web design. The optimal design, from a physical standpoint, is one that works within physical constraints.

 

For an interesting take on this, please see the linked wiki link below:

 

Spider web - Wikipedia, the free encyclopedia

 

Does this validate Lamarck's idea about "learned inheritance"? No!

 

Science does not apologize.

It moves on.

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