Origin of Instinct - Mystery or Created?

Originally posted by thehumbleone
reply to post by melatonin

 

Yippee.

Two

Interesting. So that's what they call the space between the teeth on a comb?

Learn something new everyday.

Instinct has always bothered me. Passing off not only traits but innate habits is crazy. Even without watching another organism perform the task it is still passed down. . That's insane.

You would say melatonin, that a bird covered its eggs with some grass material and then this aided its survival when other birds around it were eaten by predators. Therefore it mated with other females and spread its genes amongst the population. However, its adaptibility to the environment would then have to be genetically transmitted to its progeny.

Gosh. Lamarckism now. What next?

Permit me to add my compliments to melatonin's regarding your courage and staying power, both in this thread and more generally in the great Rearguard Action For God. Hero is a good choice of name for yourself: a tragic sort of heroism to be sure, but none the less heroic for that.

Having said which, allow me to add that if my child's biology teacher ever came out with an utterance like the one above, I'd have the sprog out of that school in a trice. Frankly, I'm shocked at such basic ignorance concerning natural selection in one of your profession.

The mutant is not the first maker of rudimentary nests - obviously - but one of its parents. The mutation takes place in one of the gametes. The first nestmaker is already genetically programmed with the new behaviour, and passes it on to its descendants through its genes, not through 'here, kids, watch Daddy and learn.'

Less obviously, perhaps, a second mutation is required. It does not have to take place at the same time; it could and probably would have occurred earlier. This mutation creates a gene for finding rudimentary nestbuilders sexy. When one of the the carriers of this gene beomes the nestbuilder's mate, the circle is closed and the stage is set for runaway sexual selection.

May I, Hero, recommend a solid, reputable popular work on sexual selection? It is The Mating Mind by Geoffrey Miller. An interesting, indeed fascinating read, not too heavy going. And he's particularly good on Fisherian runaway.

[edit on 17-2-2009 by Astyanax]

reply to post by Astyanax


err.. I hope I'm not the one above.. I just think it's interesting that's all..

reply to post by etombo

No, no, you're not the one above. My post was directed to HeroNumber0.

Welcome to the thread, I look forward to your participation. Yes, instinct is fascinating, isn't it? The more so when we realize that it is all there is. There is no free will, no mind, no soul. No matter how much rational thought is involved, the full spectrum of human behaviour and the entire edifice of human culture are the product of nothing but instinct.

reply to post by Astyanax


Hey Astyanax...

Just jumped in this forum to try and lend a hand, and read through your posts... lo and behold, you've got this place nailed down lol

Couldn't have said it better myself!

I think the disconnect for people not fully understanding is they are having a hard time extrapolating instincts, to more complex instinctual behavior... instead, they are mistaking complex "reflexes" as some sort of learned response...

I'm gonna try and explain it on simpler terms, perhaps oversimply if need be:

Breathing is a completely involuntary reflex that has been ingrained in all of us... your parents didn't teach you how to breath... no one showed you... you just did it on your own.. without any thought whatsoever...

Sexual reproduction is another instinctual urge. However, no one shows rabbits how to copulate... they seem to get along fine on their own... it is ingrained into their DNA...

Now perhaps we look at a more complex sexual animal... some animals have very very complex mating rituals. Failure to "play along" with these complex mating rituals means, well... no offspring, or propagation of the DNA... no one teaches these animals their mating rituals... but, since their DNA comes from a long line of parental DNA that had the gene for these complex rituals, they themselves have this DNA, and are genetically programmed to fulfill the mating rituals... the one's who lack this, don't reproduce... and likewise, keep their DNA out of further generations...

What some are suggesting here, is that unless parents demonstrate sex acts for their offspring... there is no way they could know how to have sex... which, of course, we know is completely ridiculous.

Hope I didn't make a mess of things... maybe I should get some coffee going so I'm firing on all cylinders this morning lol

reply to post by nj2day

What some are suggesting here, is that unless parents demonstrate sex acts for their offspring... there is no way they could know how to have sex... which, of course, we know is completely ridiculous.

Welcome to the thread, nj2day. You make a very pertinent point, since HeroNumber0 has asked us to envision a case in which young birds learn nest-building from their parents.

This may well be the first time in history anyone - even a creationist - has attributed learning skills to a bird's egg.

reply to post by Astyanax


hehe not even attributing it to the egg.... the nest is built before the egg even enters the scenario...

he's talking learning by osmosis lol

This is what surprises me. I've gave examples where young birds can be removed from their parents and still show species-specific instincts, clearly suggesting the behaviour is not learned.

ABE: And I'll add some more for fun...

Take a mouse, remove part of its front legs after birth, and they still show the species-specific grooming FAP. The mouse couldn't have learned the behaviour as the the legs were removed before co-ordinated movements could develop.

And one in the vein Hero noted earlier about hybrids...

Proc Natl Acad Sci U S A. 1997 March 4; 94(5): 2001–2006. PMCID: PMC20032

Copyright © 1997, The National Academy of Sciences of the USA
Neurobiology
Changes in multiple brain regions underlie species differences in a complex, congenitalbehavior
Evan Balaban*

The evolutionary brain modifications that produce any complex, congenital behavioral difference between two species have never been identified. Evolutionary processes may (i) alter a single, “higher” brain area that generates and/or coordinates the diverse motor components of a complex act; (ii) separately change independent, “lower” brain areas that modulate the fine motor control of the individual components; or (iii) modify both types of areas. This study explores the brain localization of a species difference in one such behavior, the crowing of chickens (Gallus gallus domesticus) and Japanese quail (Coturnix coturnix japonica). Two major subcomponents of the behavioral difference can be independently transferred with interspecies transplantation of separate brain regions, despite the fact that these components, sound and patterned head movement, occur together in a highly integrated fashion. To our knowledge, this is the first experimental demonstration that species differences in a complex behavior are built up from separate changes to distinct cell groups in different parts of the brain and that these cell groups have independent effects on individual behavioral components.

www.pubmedcentral.nih.gov...

Thus, chickens hatched from eggs with transplanted Quail neural tube cells exhibit Quail species-specific behaviours.

Yet the idea it is driven by learning is still being clung to by hero.

Hmmm.

[edit on 17-2-2009 by melatonin]

Originally posted by Astyanax

Gosh. Lamarckism now. What next?

Permit me to add my compliments to melatonin's regarding your courage and staying power, both in this thread and more generally in the great Rearguard Action For God. Hero is a good choice of name for yourself: a tragic sort of heroism to be sure, but none the less heroic for that.

Heronumber0 actually means 'No hero at all'. I am just a normal person who has to overcome his day-to-day adversities, and there are quite a lot. I have started from a 'Gee whizz - look at that complexity!' type of view and have tried to work backwards to explain it, precisely as melatonin described.

Having said which, allow me to add that if my child's biology teacher ever came out with an utterance like the one above, I'd have the sprog out of that school in a trice. Frankly, I'm shocked at such basic ignorance concerning natural selection in one of your profession.

No problem. What I normally do is to spend more time on evolution but then allow for a debate with the opposite view as a last lesson. As a consequence, I do not mention my own views at all. I allow the students to have a free reign in stating their own opinions. Remember that the level we are aiming at in school is quite low.

Now, which part do you think I show my ignorance in? I must confess my ignorance at a huge number of scientific fields. I probably do not even scratch the surface of the subject of Biology but I know enough to get by on in schools fortunately.

The mutant is not the first maker of rudimentary nests - obviously - but one of its parents. The mutation takes place in one of the gametes. The first nestmaker is already genetically programmed with the new behaviour, and passes it on to its descendants through its genes, not through 'here, kids, watch Daddy and learn.'

This is puzzling to my ignorant eyes. So what you are saying is that a mutation occurred in the gametes to change the behaviour of the birds? Do you know what you are saying? You are saying that a random mutation targeted a complex hierarchy of genes involved in the building of nests to change the type of nest building. Out of all the genes available, the precise genetic mutation was created. Do you know that even if the sequence of the genes and genomes is known, it takes up to a year of careful selection and screening to perform gene mutation in a lab. I know this because this was one of my Postdoctoral research fields.

Do you also have a knowledge of the rate of mutations? Would you understand that much of a genome is non-coding and that mutation hits in these areas do not necessarily affect genomic function.

From a brief scan of wiki, I came up with this:

More generally, the mutation rate in eukaryotes is in generally 10-4 to 10-6 mutations per base pair per generation[4], and for bacteria the rate is around 10-8 per base pair per generation[5]. The highest mutation rates are found in viruses, which can have either RNA or DNA genomes. DNA viruses have mutation rates between 10-6 to 10-8 mutations per base per generation, and RNA viruses have mutation rates between 10-3 to 10-5 per base per generation[5]. Human mitochondrial DNA has been estimated to have mutation rates of ~3×10-6 or ~2.7×10-5 per base per 20 year generation (depending on the method of estimation)[6]; these rates are considered to be significantly higher than rates of human genomic mutation at ~2.5×10-8 per base per generation[1].

Link

What I am saying here is that it is quite unlikely that germ line (sperm or egg) mutations would target a hierarchy of nest building genes.

After this amazingly fortuitous event, the mutation would then be passed on to a 'normal' female let's say. The female's chicks would then have one mutated chromosome and one normal (or wild type) chromosome. You have created hybrid chicks which would exhibit both behaviours or a mixture of both, or neither- something called displacement behaviour.

Less obviously, perhaps, a second mutation is required. It does not have to take place at the same time; it could and probably would have occurred earlier. This mutation creates a gene for finding rudimentary nestbuilders sexy. When one of the the carriers of this gene beomes the nestbuilder's mate, the circle is closed and the stage is set for runaway sexual selection.

After all the comments I have made above about the extremely rare nature of mutations, you are now suggesting a second mutation Astyanax.
Shall we go back a step. And please don't offer your own opinions as fact as Darwinian supporters are likely to do.

The weaver bird must make one knot to a branch. This knot is crucial to the survival of the species. Can you Astyanax, or other Darwinians come up with a crucial step-by-step method for where the survival advantage of tying that first knot comes from? Moreover, the birds also have to make a large loop as a sort of strut for the nest.

Can you please suggest a step-by-step method of how the birds that can make such a structure will survive over those who don't? I suggest you cannot address the arguments I have made above. The sheer complexity of the processes that underly instinct are enormous and mind-blowing.

In my opinion, God has introduced complexity from every organism down to a single cell. He is revealing His artistry and genius down to every protein made by every cell of every weaver bird. It cries Design from every hilltop. I don't expect you to buy into this because you will do your gap-filling with the old words: "Infinite Time - Infinite mutation - Infinite Natural Selection."

Fisherian runaway is a more plausible mechanism for mate selection which I find reasonably appealing, although I have yet to consider it in more detail. I do also think that Natural Selection is one of God's biological Laws but you would never listen anyway.

May I, Hero, recommend a solid, reputable popular work on sexual selection? It is The Mating Mind by Geoffrey Miller. An interesting, indeed fascinating read, not too heavy going. And he's particularly good on Fisherian runaway.

Thank you for the reference. I don't have much time to read though except for what is easily available on the net; my family are far too important to allow me much reading time.

Peace.

Originally posted by melatonin

Perhaps nest making was already around before birds evolved. Some birds just plop them on the ground, others make minor modifications, some dig holes, and more make more elaborate nest sites. It's just a refuge for eggs, and depending on other variables would depend the effort made.

How would a behaviour change find its way into the genome by inheritance unless it is taught.

My faux pas here. Never mind. I was referring to the unlearned nature of instinct. That was my initial working definition. Therefore the origin of instinct is still a mystery. I think, melatonin, you do separate opinion from fact unlike other Darwinian supporters who suddenly become complete experts on their subject and attempt to plausibly explain away the gaps by their own opinions. An unwise move.

by melatonin

Cell, Volume 121, Issue 5, 785-794, 3 June 2005

doi:10.1016/j.cell.2005.04.027

fruitless Splicing Specifies Male Courtship Behavior in Drosophila
Ebru Demir and Barry J. Dickson,

Institute of Molecular Biotechnology of the Austrian Academy of Sciences, Dr. Bohr-Gasse 35, A-1030 Vienna, Austria

Summary
All animals exhibit innate behaviors that are specified during their development. Drosophila melanogaster males (but not females) perform an elaborate and innate courtship ritual directed toward females (but not males). Male courtship requires products of the fruitless (fru) gene, which is spliced differently in males and females. We have generated alleles of fru that are constitutively spliced in either the male or the female mode. We show that male splicing is essential for male courtship behavior and sexual orientation. More importantly, male splicing is also sufficient to generate male behavior in otherwise normal females. These females direct their courtship toward other females (or males engineered to produce female pheromones). The splicing of a single neuronal gene thus specifies essentially all aspects of a complex innate behavior.

Swapping a single gene between male and female swaps their courtship behaviours. Females perform male courtship behaviours to females when given the male allele.

Interesting one this. If you read the caveat from the Press release you presented, it is quite interesting:

The concept that a switch gene can specify an entire innate behaviour in no way denies the critical role of
complex gene networks, just as, for the physical building plan of an animal, the concept of a morphogenetic
switch does not deny the existence of complex regulatory networks among the genes it regulates. These
networks add both detail and robustness to the behavioural or morphological pattern initially laid down by the
switch gene at the top of the hierarchy.

Press release discussion of the workhere.

In fact, the change in transcription of the fruitless gene affects quite a number of genes. As I said, it is likely that single gene knockout to change an FAP/instinctive behaviour is actually multigenic in its influence hence the tentative language used by the researchers from the Press release.

Genomic and Functional Studies of Drosophila Sex Hierarchy Regulated Gene Expression in Adult Head and Nervous System Tissues
Thomas D. Goldman 1 , Michelle N. Arbeitman 1 ,2*
1 Section of Molecular and Computational Biology, Department of Biological Sciences, University of Southern California Los Angeles, Los Angeles, California, United States of America, 2 Section of Neurobiology, Department of Biological Sciences, University of Southern California Los Angeles, Los Angeles, California, United States of America
Abstract
The Drosophila sex determination hierarchy controls all aspects of somatic sexual differentiation, including sex-specific differences in adult morphology and behavior. To gain insight into the molecular-genetic specification of reproductive behaviors and physiology, we identified genes expressed in the adult head and central nervous system that are regulated downstream of sex-specific transcription factors encoded by doublesex (dsx) and fruitless (fru). We used a microarray approach and identified 54 genes regulated downstream of dsx. Furthermore, based on these expression studies we identified new modes of DSX-regulated gene expression. We also identified 90 and 26 genes regulated in the adult head and central nervous system tissues, respectively, downstream of the sex-specific transcription factors encoded by fru. In addition, we present molecular-genetic analyses of two genes identified in our studies, calphotin (cpn) and defective proboscis extension response (dpr), and begin to describe their functional roles in male behaviors. We show that dpr and dpr-expressing cells are required for the proper timing of male courtship behaviors.

Link to Paper

By the behaviour being genetically mediated in the first place. I think astyanax summarised it much more eloquently than I. If the genetically-mediated behaviour is open to variation, then selection can act. I'll send you back to the initial study about homology and grooming FAPs in rodents.

It takes quite a lot of variation to make a knot

I think FAPs are a form of instinct by their very nature. I suppose it's not impossible for certain learned behaviours to become instinctive over time. Maybe. The problem is that you want to make a very clear distinction between instinct and learning. As noted earlier, instincts can be influenced by experience. For example, birds will develop their species specific song when raised in a sound proof area, but can still learn more complex song when eventually exposed to other bird's songs.

I repeated my mistake here but I was referring to the appearance of an adaptive behaviour. For example, if a bird can make a more complex but greater load bearing structure then the correct genes for the adaptation have to be either:

a) selected for;
or b) passed on to the next generation.

The easiest way for the selection would have to be by an extraordinary success of predators or for the successful bird to be extraordinarily promiscuous in order for that genetic structure to be inherited. Moreover any mutation would have to be extraordinarily successful as well. But I suppose infinite Time does have its advantages...







[edit on 17/2/2009 by Heronumber0]

Originally posted by Heronumber0
So what you are saying is that a mutation occurred in the gametes to change the behaviour of the birds? Do you know what you are saying?

Yes.

You are saying that a random mutation targeted a complex hierarchy of genes involved in the building of nests to change the type of nest building.

Do you know what's wrong with this sentence? One word: 'targeted'.

Teleology again. We're speaking of random occurrences here. I'll come back to that.

Out of all the genes available, the precise genetic mutation was created.

Many others occurred (or 'were created'). Some were deleterious, and their owners died out. Some were selectively neutral for the nonce and hung around in the population without doing much. A few of these, like the gene for finding nestbuilders sexy, ultimately ended up conferring a selective advantage in combination with a subsequent mutation. And some - a very, very few - conferred an advantage in their own right.

Do you know that even if the sequence of the genes and genomes is known, it takes up to a year of careful selection and screening to perform gene mutation in a lab.

To perform a previously specified mutation? A targeted mutation? I imagine it would take some time. In my ignorance I'd be willing to believe it took ten years. Not the point.

Do you also have a knowledge of the rate of mutations? ...From a brief scan of wiki, I came up with this:

More generally, the mutation rate in eukaryotes is in generally 10-4 to 10-6 mutations per base pair per generation... these rates are considered to be significantly higher than rates of human genomic mutation at ~2.5×10-8 per base per generation[1].

Following the link in the footnote given above, I found

The average mutation rate was estimated to be ~2.5 x 10-8 mutations per nucleotide site or 175 mutations per diploid genome per generation.

Source

175 mutations per diploid genome. The source looks fairly kosher to me. Am I displaying my ignorance here, or isn't a eukaryotic diploid genome the full set of genes for an individual? Doesn't that mean each individual human being is a mutant 175 times over? Gosh, that's a lot of mutations. How many, then, must have taken place over the tens of thousand of generations that Homo has been Sapiens?

The human genome has, what, three billion base pairs? Sounds like there's been been time enough to mutate every single base pair on the genome.

But - since I am not a biologist - I could be totally ignorant of a hundred reasons why this cannot be so. I am willing to learn; teach me.

Still - one way or another - there seems to be quite a lot of natural mutation going on. And that's in humans, whose mutation rate is considerably lower than for most other eukaryotes... how do bird rates compare? Okay, a wild bird population is likely to be far lower than the obscene human figure of six and a half billion, but then again, what's a bird generation? Birds - there may be some exceptions, but as a rule - take about a year to reach sexual maturity.

Sounds like plenty of time for those nestbuilding birds to mutate. All the time in the world.

Because, remember, it's random. The chance of a useful mutation is vanishingly small - but any mutation can be that mutation. It's not targeted: if someone's flinging cosmic-ray bolts, he's not taking aim and he doesn't have to. Because it doesn't matter that most mutations are pointless or harmful. What matters is there are so many.

What I am saying here is that it is quite unlikely that germ line (sperm or egg) mutations would target a hierarchy of nest building genes.

Why not? Everything we are, all our amazing elaboration from embryos to Heroes, is already encoded in our genes, to be unfolded in ways that are susceptible to modification by our environments. It follows that a mutation in a gamete can affect any gene or genes - and thus affect any kind of behaviour, nestbuilding included.

After this amazingly fortuitous event, the mutation would then be passed on to a 'normal' female let's say. The female's chicks would then have one mutated chromosome and one normal (or wild type) chromosome. You have created hybrid chicks which would exhibit both behaviours or a mixture of both, or neither- something called displacement behaviour.

Why can't one gene be expressed and its counterpart on the other chromosome recessive? Happens all the time. People with one blue and one brown eye aren't that common.

Shall we go back a step. And please don't offer your own opinions as fact as Darwinian supporters are likely to do. The weaver bird must make one knot to a branch...

No, Teacher, let's not go back a step. Confound the knot and to perdition with the branch. You are trying to insist that evolution must have happened the way you say it did. Instead of thinking of how some bird could must suddenly have upped and tied a pefect knot from scratch, try to imagine how a weaverbird's nest might have evolved. It strikes me as a much more fruitful line of inquiry.

The sheer complexity of the processes that underly instinct are enormous and mind-blowing... His artistry and genius down to every protein made by every cell of every weaver bird... Natural Selection is one of God's biological Laws.

We are indeed a part of, completely permeated by, and act in the presence of something that can most fittingly be called God. By all means speak of natural selection as God's law, if it comforts you; speak also of the great universal laws, the laws of motion, of thermodynamics, of gravitation in such terms - why not? But I conceive of this God as no external agent, no uncaused Cause hiding in the wings of Creation. It is simply the Universe, what Christians call the World. Such is what you would call my blasphemy, for to you I embrace Creation and spurn the Creator. But for me - an atheist withal - Creator and Creation are one and the same.

I trust you will forgive the slight digression. You are not the only one who has thought long and hard on these matters.

I am sorry you have no time to read. It is a deprivation I would wish on no-one.
*I use the term in the ancient, not the modern sense.

reply to above posters


Why is it not okay for a weaver bird to tie a knot out of nowhere, when at some point in time humans did the same thing?

It is instinct. An organism will adapt in whatever way necessary to its environment in order to survive. The adaptations are random mutations that occur in DNA and the best mutations are the ones that stick. For instance, at some point, the ancestral organism to ducks did not have webbed feet. But then randomly, one did, just how randomly one probably was born with three legs. The one with webbed feet ended up being able to survive better, and after a long time, the mutation became more common and stuck. The one with three legs had trouble getting around and didn't survive as well, so it didn't stick and ducks kept on having two legs. The webbed feet are like the ability to tie knots. Intelligence is just an adaptation, after all. The birds who tied knots had better nests. They were more waterproof, maybe more protected, maybe just randomly survived better than the other nests. So therefore, the birds who tied knots survived more often. And that's why they tie knots.

Evolution is a really, really simple concept to understand unless you're already set on a different, less logical concept. There is enough evidence around to support the fact that instinct is a result of DNA and the need for survival that I can't even believe this discussion is actually going on. Well, I mean, I can, because some people just choose to believe one (less probable) theory over another (more probably) theory.

By the way, you can believe in evolution and God (apparently, I've been told.)
So, the instinct goes with the evolution part. That's what the religious naturalists will tell you. The God part goes with the creation aspect, I guess. Maybe God created evolution. Does that make you feel better?

[edit on 2/17/2009 by ravenshadow13]

Originally posted by Heronumber0
In fact, the change in transcription of the fruitless gene affects quite a number of genes. As I said, it is likely that single gene knockout to change an FAP/instinctive behaviour is actually multigenic in its influence hence the tentative language used by the researchers from the Press release.

Quite probably. Of course, I'm trying to show the genetic underpinnings of such instincts. In other words, contrary to the last few posts, they are not driven by learning. They can be honed, of course.

You've essentially given way to the argument for evolution. Well done. Multigenic and therefore open to variation and selection.

Cool.

It takes quite a lot of variation to make a knot

Does it? The mouse grooming FAP has 25 serial elements. I'm quite sure that's more than a knot - in-out, twist about.

I repeated my mistake here but I was referring to the appearance of an adaptive behaviour. For example, if a bird can make a more complex but greater load bearing structure then the correct genes for the adaptation have to be either:

a) selected for;
or b) passed on to the next generation.

Aye, if the females prefer such nest features then it is likely to passed on. Hence selected for and passed on.

The easiest way for the selection would have to be by an extraordinary success of predators or for the successful bird to be extraordinarily promiscuous in order for that genetic structure to be inherited. Moreover any mutation would have to be extraordinarily successful as well. But I suppose infinite Time does have its advantages...

Not really. Just a minor tweek can alter the balance sufficiently. Then, as you note, time helps. If females tend to have a predisposition for particular nests, then over time - lots of ubernests. Remember, many species don't actually respond to the exact natural phenomena. For example, I can't recall the exact name, but many instincts respond to what I'll call 'super'-stimuli. Thus, female sticklebacks prefer crude models of a red-bellied male than a true model likeness. It is particular sensory features they respond to (a small red object), not the male/female/egg/nest etc.

Anyway, as I said, we're going in circles and I'd rather not. I present studies from a range of areas studying the neural and genetic underpinnings of instincts (I noted you ignored the Quail study) and even phylogenetic relationships between FAPs, yet you fixate and perseverate on weaving and knots. Take care, Hero.

[edit on 17-2-2009 by melatonin]

from Atyanax

Do you know what's wrong with this sentence? One word: 'targeted'.

Teleology again. We're speaking of random occurrences here. I'll come back to that.

Let me explain, happy in my ignorance. There are likely to be millions of spermatozoa. If the correct mutation is randomly in one of the millions of sperm then that spermatozoa carrying the mutation must perform the fertilisation. You are the mathematician - go figure what the chances are if a handful of spermatozoa carrying mutations amongst millions, and one of the mutations, rather than healthy spermatozoa being successful at performing a fertilisation. Quite difficult huh?

Many others occurred (or 'were created'). Some were deleterious, and their owners died out. Some were selectively neutral for the nonce and hung around in the population without doing much. A few of these, like the gene for finding nestbuilders sexy, ultimately ended up conferring a selective advantage in combination with a subsequent mutation. And some - a very, very few - conferred an advantage in their own right.

Do you know, you, I and melatonin are going round in circles. I have asked this question about actions that have no selective advantage on their own as being selected and it has been ignored because Darwinians prefer their own guesswork to actually answering a set question. I'll tell you what, ignore my question about the evolution of nest building instinct altogether and also how instinct can be adaptive, change and then be 'embedded in the brain' just give me more of the dogma again as you have done. This is now getting repetitive.

More generally, the mutation rate in eukaryotes is in generally 10-4 to 10-6 mutations per base pair per generation... these rates are considered to be significantly higher than rates of human genomic mutation at ~2.5×10-8 per base per generation[1].

Following the link in the footnote given above, I found

The average mutation rate was estimated to be ~2.5 x 10-8 mutations per nucleotide site or 175 mutations per diploid genome per generation.

Source

175 mutations per diploid genome. The source looks fairly kosher to me. Am I displaying my ignorance here, or isn't a eukaryotic diploid genome the full set of genes for an individual? Doesn't that mean each individual human being is a mutant 175 times over? Gosh, that's a lot of mutations. How many, then, must have taken place over the tens of thousand of generations that Homo has been Sapiens?

You are right. Humans carry about a hundred mutations but remember that most mutations end up in non- coding regions otherwise even a single change in a coding gene can lead to disastrous consequences, for example bladder carcinoma, if my memory serves me correctly.

The human genome has, what, three billion base pairs? Sounds like there's been been time enough to mutate every single base pair on the genome.

But - since I am not a biologist - I could be totally ignorant of a hundred reasons why this cannot be so. I am willing to learn; teach me.

Which would change us from being humans then. But then the appearance of humanity is debated by Darwinians and Creationists, isn't it? You don't want to be taught anything, you just want to confirm your own closed position.

Sounds like plenty of time for those nestbuilding birds to mutate. All the time in the world.

Because, remember, it's random. The chance of a useful mutation is vanishingly small - but any mutation can be that mutation. It's not targeted: if someone's flinging cosmic-ray bolts, he's not taking aim and he doesn't have to. Because it doesn't matter that most mutations are pointless or harmful. What matters is there are so many.

Just a couple of objections and indulge me with these:

1) Mutations are more likely to land in no-coding areas of the genome (non-protein coding);
2) Mutations have to be specific to the nest building process - for example in the weaving process and have to be in the cascade of genes that are likely to affect the instinct - single gene knockout studies affect a number of subsidiary genes in my opinion from what I have read.
3) In diploid species, a mutation in one gene on a chromosome will be normally recessive (except for Huntington's allele which is dominant) because the healthy gene/allele will cover up the effects of the mutation. For example the cystic fibrosis allele will have its effect masked by the healthy allele on the other chromosome.

Why not? Everything we are, all our amazing elaboration from embryos to Heroes, is already encoded in our genes, to be unfolded in ways that are susceptible to modification by our environments. It follows that a mutation in a gamete can affect any gene or genes - and thus affect any kind of behaviour, nestbuilding included.

Answered above Asty.

Why can't one gene be expressed and its counterpart on the other chromosome recessive? Happens all the time. People with one blue and one brown eye aren't that common.

Correct me if I am wrong on this but I believe the condition is called heterochromia iridis and is environmental in origin:

Link to Heterochromia

No, Teacher, let's not go back a step. Confound the knot and to perdition with the branch. You are trying to insist that evolution must have happened the way you say it did. Instead of thinking of how some bird could must suddenly have upped and tied a pefect knot from scratch, try to imagine how a weaverbird's nest might have evolved. It strikes me as a much more fruitful line of inquiry.

I did ask you not to give your opinions but all you have done so far is to regurgitate Darwinian Natural Selection. And it is not enough Asty. If a bird ties a perfect knot to start the crucial process of nest building, where is the selective advantage? No answer! I thought so.

We are indeed a part of, completely permeated by, and act in the presence of something that can most fittingly be called God. By all means speak of natural selection as God's law, if it comforts you; speak also of the great universal laws, the laws of motion, of thermodynamics, of gravitation in such terms - why not? But I conceive of this God as no external agent, no uncaused Cause hiding in the wings of Creation. It is simply the Universe, what Christians call the World. Such is what you would call my blasphemy, for to you I embrace Creation and spurn the Creator. But for me - an atheist withal - Creator and Creation are one and the same.

If you wish. I am not trying to convince you of my world view. All I wanted to do was to discuss the origin of instinct in animals.

I trust you will forgive the slight digression. You are not the only one who has thought long and hard on these matters.

I forgive you, you did not even need to mention it.

My main point again. In the weaver bird (using at least three complex knots), the Yucca moth and how termites build their nests and organise their societies by instinct which is unlearned is difficult to explain because, although there is likely to be variation and Natural Selection it is difficult to point out how it originated. Some of the people who kindly responded to my enquiries tried to speculate how mutation and selection gave rise to these complex brain-embedded behaviours. I agreed that the environment and photoperiodism mediated by the neuroendocrine system are involved and I never doubted that. However, I do doubt that knocking out single genes can change an instinct because there seem to be cascades of genes involved a la Professor Behe. We end up with a giant question mark and gaps - the gaps are either due to God or to Mutations + Infinite/incomprehensible Time

reply to post by Heronumber0


You're letting the numbers daunt you again...

Suppose there is a 1 in a billion chance of something happening... now... repeat the experiment 100 billion times...

There's a statistical probability of this unlikely event happening 100 times out of that 100 billion...

now suppose that 1 off chance actually produced something beneficial to the species... something that improved their odds of spreading their DNA to offspring... who now have a leg-up to thwart the forces of natural selection...

Many mutations aren't benificial for survival.... at first...

Suppose this mutation is carried on part of the DNA that isn't currently used... but, for some reason, in the future, it gets clicked into the "on" position... Now suddenly, that DNA mutation happens to be beneficial for survival..

This is genetic drift... you seem to be arguing from a position that genetic drift isn't all that "powerful"... but, ask someone with cancer...

It takes 7 very specific genetic mutations for a cell to become cancerous... that doesn't seem like very good odds to me... but... given the amount of cells in each human body, multiplied by the amount of humans running around... means that the improbability of these 7 specific mutations happening is overcome... and thus we have cancer... these mutations are VERY benificial to the cancerous cells, as it inhibits all checks and balances to keep the cell from dividing (reproducing itself), and allows it to propagate uncontrollably...

Here's something for you to ponder....

www.timesonline.co.uk...

Scientists find evidence that monkeys have a sense of morality!

by nj2day
You're letting the numbers daunt you again...

Suppose there is a 1 in a billion chance of something happening... now... repeat the experiment 100 billion times...

There's a statistical probability of this unlikely event happening 100 times out of that 100 billion...

Hi nj2day. Thank you for the point you made. If an unlikely event happened a hundred times, then it would have to hit the same target gene in a diploid organism on both chromosomes. I suppose we are talking of hitting a spot on the Sun with a rocket fired from the Earth with no direction.

However, if that direction was planned by a Great Planner who set all the initial switches to make evolution happen, then yes, I could accept that. If the Great Planner then allowed for intervention when the human brain had reached the correct level by introducing a soul into humans and a lesser soul into animals (i.e. limited consciousness) then I could believe that too and I would happily believe in God and evolution.

Only one problem though, evolution excludes the possibility of dualism, of the ghost in the machine, and therefore forces me to look back to God and His Design again. As soon as I look back at the Design argument - and it has its faults - no doubt, I am reminded of Professor Behe's comment about the evolution of a photon sensor (to sense light). There would have to be a mechanism that caused a mutation to sense light but that would have to wait and be selected for by Natural Selection for potentially millions of years until the mechanism came along to recycle the pigment that detected the light. Then the mechanism would have to be selected for for another few million years until another mechanism came about which linked the motor system and caused the organism to react to movement as soon as it detected the reflected light off another animal. It's a long wait.

by nj2day now suppose that 1 off chance actually produced something beneficial to the species... something that improved their odds of spreading their DNA to offspring... who now have a leg-up to thwart the forces of natural selection...

Many mutations aren't benificial for survival.... at first...

Suppose this mutation is carried on part of the DNA that isn't currently used... but, for some reason, in the future, it gets clicked into the "on" position... Now suddenly, that DNA mutation happens to be beneficial for survival..

That is actually quite a good theory. So a neutral mutation then suddenly comes into being with a selective advantage - hmmm. Any reference nj?

This is genetic drift... you seem to be arguing from a position that genetic drift isn't all that "powerful"... but, ask someone with cancer...

It takes 7 very specific genetic mutations for a cell to become cancerous... that doesn't seem like very good odds to me... but... given the amount of cells in each human body, multiplied by the amount of humans running around... means that the improbability of these 7 specific mutations happening is overcome... and thus we have cancer... these mutations are VERY benificial to the cancerous cells, as it inhibits all checks and balances to keep the cell from dividing (reproducing itself), and allows it to propagate uncontrollably.

Interesting information - I thought there were 7 stochastic events, any one of which in excess could produce cancer. However, the state of the immune system is also important. How does it cause a genetic change? And how does the wrong diet cause a specific genetic change?

I did a quick search and came up with this:

The many causes of cancer
Carcinogens
Age
Your genetic make up
Your immune system
Your diet
Your day-to-day environment
Viruses

Link to Cancer Site

Also, I thought that organisms had powerful mechanisms inside them to cope wih genetic mutation by correcting the mutation during DNA replication. If memory serves me right, then DNA polymerase I has proof reading functions that will correct mistakes.

But I take the point you originally made about genetic drift. I don't particularly disbelieve in it. I just don't know how it would lead from a Fixed Action Pattern to an instinct embedded in the brain.

You also gave me a link to say that monkeys have a sense of morality and one genus has a more advanced form of it than others suggesting that the cause is genetic. I am reading it up just now and we can discuss it when I have formulated some thoughts on it.

Thank you for the contribution

reply to post by Heronumber0


Here's your link with the cancer information...

health.usnews.com...

I had another earlier that stated that on average, 7 specific genetic mutations are required to complete the genetic pathway for cancer to develope... out of the 7, two are capable of being passed down through heridity...

meaning... if you inherit the gene for cancer, you are already 2 steps ahead in accumulating these mutations than someone who didn't inherit them...

Interesting information - I thought there were 7 stochastic events, any one of which in excess could produce cancer. However, the state of the immune system is also important. How does it cause a genetic change? And how does the wrong diet cause a specific genetic change?

If you notice the list... they all are sort of inter-related... Diet and age effect immune system... etc... its all about accumulating these mutations...

"Rogue cells" do have a chance to get caught by the immune system before they become full on cancer/tumors... btw


Anyway, I'll keep looking for my source document that names specifically 7 mutations...

Point of interest:

They have discovered 12 different "pathways" for these mutations to result in cancer... which means, there are 12 different sets of 7 mutations.... all leading to cancer




[edit on 18-2-2009 by nj2day]

Here's your link with the cancer information...

health.usnews.com...

I had another earlier that stated that on average, 7 specific genetic mutations are required to complete the genetic pathway for cancer to develope... out of the 7, two are capable of being passed down through heridity...

meaning... if you inherit the gene for cancer, you are already 2 steps ahead in accumulating these mutations than someone who didn't inherit them...

If you notice the list... they all are sort of inter-related... Diet and age effect immune system... etc... its all about accumulating these mutations...

"Rogue cells" do have a chance to get caught by the immune system before they become full on cancer/tumors... btw


Anyway, I'll keep looking for my source document that names specifically 7 mutations...

Point of interest:

They have discovered 12 different "pathways" for these mutations to result in cancer... which means, there are 12 different sets of 7 mutations.... all leading to cancer

[edit on 18-2-2009 by nj2day]

You are right and the information is in your link. Researchers are busy mapping the cancer genome:

What is the cancer genome, anyway?
Cancer, by definition, is caused by genes going haywire—mutating in ways that are not part of the normal blueprint for the body's form and function. Even among tumors of a single type, those genes can go haywire in many different ways. So describing the entire cancer genome involves characterizing all the different abnormalities that are linked to each of the 50 major types of cancer. That daunting task would involve churning through 12,500 times as much information as scientists processed in their recently completed effort to map the entire human genome.

Link to Cancer Gene Mapping

However the relatively rare effect of cancer mutations seems to indicate that humans, at least, have very powerful mechanisms to keep mutations at bay or to correct mistakes in the DNA sequence. Otherwise, we would all have cancer...