Seven Questions for Neo-Darwinists

[dron]

Hello. I have seven questions for neo-darwinists, supporters and readers of Dawkins, Dennet, Pinker and company, and sympathisers for the "selfish gene" theory.

1. I have read that "sperm can take up DNA" and that "new genetic and phenotypic features, unlinked to chromosomes, can thus be generated and inherited in a non-Mendelian ratio." Does this mean, or at least suggest, that the "selfish gene" is not the final arbiter of behaviour? Does any evidence (I'm thinking of investigations into inherited characteristics of rats and in the health and survival potential of children from stressed mothers) suggest a more Lamarckian view of "phenotypical power"?

2. Is it true that continental scientists are less interested in neo-darwinism than anglo-american biologists? If so, what theories do they favour?

3. Is it true that favourable mutations would soon be lost by interbreeding with non-mutated members of a species, that Darwin himself saw this as the biggest problem of his theory, and that neo-Darwinists have never convincingly solved it?

4. What is the survival value of looking up into the night and enjoying the starry sky?

5. I have read that mutations only occur at a rate of about one per several million cells in every generation, and that, since only a tiny number create beneficial traits which give a survival advantage, this is not fast enough to account for the extraordinary natural world, or for the rapidity that some species seem to change under environmental stress.

5. The consequence of a neo-darwinism is a non-altruistic, hierarchical and competitive world (cooperation only occurring between people likely to share the same genes). How can one explain the non-hierarchical, non-warlike and egalitarian behaviour of many hunter-gatherers, sedentary tribal people, and pre-ayrian cultures like Catal Huyuk, "Minoa" and the early Europeans described by Gimbutas and Campbell?

6. Pinker believes that we write poems and symphonies in order to achieve status. Does this effectively explain the behaviour and creations of artists?

7. Quantum physics is irrational, the neo-darwinist world is rational. Is there not a problem here? Why should the universe only exhibit irrational behaviour on the smallest scales? Is it not likely that if the fundamental units of existence are irrational that this might lead to irrational effects in the macro world - the kind of religious forces and experiences Dawkins dismisses out of hand (and I am not talking about the abrahamic religions here, which are easy targets, the only ones Dawkins aims at).

Thank you,

Darren

 

[SizarieldoR]

4. What is the survival value of looking up into the night and enjoying the starry sky?

5. The consequence of a neo-darwinism is a non-altruistic, hierarchical and competitive world (cooperation only occurring between people likely to share the same genes). How can one explain the non-hierarchical, non-warlike and egalitarian behaviour of many hunter-gatherers, sedentary tribal people, and pre-ayrian cultures like Catal Huyuk, "Minoa" and the early Europeans described by Gimbutas and Campbell?

7. Quantum physics is irrational, the neo-darwinist world is rational. Is there not a problem here? Why should the universe only exhibit irrational behaviour on the smallest scales? Is it not likely that if the fundamental units of existence are irrational that this might lead to irrational effects in the macro world - the kind of religious forces and experiences Dawkins dismisses out of hand (and I am not talking about the abrahamic religions here, which are easy targets, the only ones Dawkins aims at).

4. None. But it could be the side-effect of some sort of innate desire that WAS implanted in the species by natural selection.

5. Maybe they are like the ants or termites. There is no competition between individual workers in a bee hive after all and they work as a big team. Or, among these human individuals, natural selection may have stopped because they are so clever that they can cooperate and coordinate and work as a team. In terms of game theory, teamwork is advantageous. Being nice to the rest of the "team" makes the work easier and the team more efficient.

7. On very small scales it is weird, but on human scales, rationality prevails.

 

[hypatia]

Is this homework?

 

[Cincinnatus]

I'm not completely sure what you mean by "neo-darwinism" since this phrase seems to mean different things to different people. However, you mostly speak of Dawkins, Dennet, Pinker etc. These guys a espouse a view of evolution that might be called "adaptationist". Rather than answering your specific questions I think it would be clearer to attempt a more full explanation of the adaptationist program.

------

"If evolution is the answer, then what is the question?"

This isn't as silly as it sounds. There are different views about what evolution is trying to explain. For Dawkins et al the question has to be something like "why are organisms so superbly adapted to their environments?". The goal can be seen as a justification of the logic that let's you answer questions like "why are we altruistic?". This is in contrast with other views of evolution which view the central fact to be explained as "why is life so diverse?". For such views, questions of "teleology" that is, "purpose" in evolution are probably nonsensical.

By mentioning teleology, I don't mean to make it sound like Dawkins et al are talking about some kind of "higher purpose" or "guided" evolution that groups like the Catholic church and various Jewish organizations love to talk about. Dawkins' view can be thought of as a way to make sense of teleology in strictly nonreligious terms. Put another way, before Dawkins it was hard to hold evolution as a true theory and still answer questions like "why did this or that evolve?" The answers would then include words like "kin selection" and "fitness" rather than "design and plan" like the guided evolution people would use.

I don't mean to say that teleology questions were not answered by evolution's supporters before Dawkins but rather that Dawkins et al made major contributions to how we think about some of these questions today. The major one was the explanation of altruism which was basically the motivation for the notion of the selfish gene.

If evolution is to explain anything then a method by which traits are selected to be passed on to the next generation needs to be specified. Obviously the actual fitness values of any particular trait are very highly environmentally determined. What is needed are general principles by which we can reason about these things despite not knowing everything about the past environment.

Another way of saying the same thing is that we need to decide "at what level" does natural selection operate. Should we assign fitness values to organisms? To species? Or perhaps to individual genes?

Enter the notion of the selfish gene. Dawkins observed that there are just 3 requirements for "an individual" to evolve by natural selection.

1). Individuals reproduce themselves and offspring resemble their parents.

2). There is variation in the reproductive performance of individuals in the populations.

3). Individuals compete for resources needed to reproduce.

(Note: you could probably come up with a more satisfying formalization of these three requirements but for the purposes of this explanation these will suffice)

Now if you replace the word "individual" with "organism" in the above requirements then they will still make sense. Indeed, we can say that organisms evolve. Dawkins' pointed out that explanations at the level of the organism (or higher) fail for various reasons which I won't go into here. He also pointed out that genes themselves satisfy those 3 requirements.

Thus we have the notion of the "selfish gene". Dawkins speaks of organisms as "survival machines" which allow genes to survive in the environment long enough to make more copies of themselves.

Dawkins wasn't the first to introduce the notion that genes are the unit of selection. That is, genes are the proper entities which should be assigned fitness values and "selected" to move on to the next generation (or not to). Though Dawkins popularized this view (even among scientists) with his famous 1976 publication of The Selfish Gene.

Roughly, the evolution of altruism can now be explained since the exact same gene may exist in many copies across organisms. If there were a gene "for altruism" then we could expect it to spread throughout the population since it would cause organisms to help each other and thereby increase the probability of more copies of the altruism gene to end up in the next generation.

This selfish gene logic has provided us with an evolutionary teleology that is internally consistent and requires no appeal to outside entities. Thus the goal of the adaptationist program is fulfilled.

The above paragraph is a gross simplification of Dawkins' view of the evolution of altruism. If you found any of this interesting (or annoying) then I urge you to read Dawkins' actual book. The Selfish Gene is very readable and of course he does a much better job explaining all of this than I...

 

[dron]

I have read the book in question, which I understand, but which doesn't answer my questions. I cannot, alas, understand how your post answers my questions either (although I am grateful for your time). Could you explain?

Dawkin's ideas may be "internally consistent" but they do not seem to be consistent with reality, as I experience it. My questions are an attempt to clear up the error - his or mine.

 

[Dale]

7. Quantum physics is irrational

no it isn't. What makes you think this?

 

[vociferous]

I am not a biologist, so I will only answer the questions I feel confident in.

3. Is it true that favourable mutations would soon be lost by interbreeding with non-mutated members of a species, that Darwin himself saw this as the biggest problem of his theory, and that neo-Darwinists have never convincingly solved it?

No, this is not true, as observational evidence indicates. Of course, some mutations could become lost this way, but certainly not all of them.

4. What is the survival value of looking up into the night and enjoying the starry sky?

This is not a properly framed question (based upon what I believe you are attempting to imply). It would be similar to asking, "what is the survival value of not being able to breath under water?" In the later case, it evolved as a consequence of being able to breath better on land, and in the later, it likely was a consequence of greater intelligence and inquisitiveness, that had an important "survival value" for what should be obvious reasons.

I have read that mutations only occur at a rate of about one per several million cells in every generation, and that, since only a tiny number create beneficial traits which give a survival advantage, this is not fast enough to account for the extraordinary natural world, or for the rapidity that some species seem to change under environmental stress.

I doubt that there is really a significant observational and theoretical basis for making such an a priori claim. As in everything, science is based on inductive logic, and this is what we learn from observing and testing the natural world, so any a priori claim such as the one you postulate is not going to be considered valid until it is shown to be true empirically.

7. Quantum physics is irrational, the neo-darwinist world is rational. Is there not a problem here? Why should the universe only exhibit irrational behaviour on the smallest scales? Is it not likely that if the fundamental units of existence are irrational that this might lead to irrational effects in the macro world - the kind of religious forces and experiences Dawkins dismisses out of hand (and I am not talking about the abrahamic religions here, which are easy targets, the only ones Dawkins aims at).

Quantum physics is not "irrational". This is a false premise; it is akin to saying that cricket is "irrational" because the rules are different than baseball. Our ability to understand the quantum world differs greatly from the classical world, but it is hardly "irrational". Rather, on the quantum world, we are unable to take measurements without affecting what we are measuring, thus we can only make a probabilistic determination of the behavior of a single subatomic particle, but all the perturbations average out and result in the behavior of the world of classical physics.

So, to sum this question up.

1) The quantum world is not "irrational".
2) The unpredictability in the subatomic world averages itself out into the very predictable classical world. Quantum mechanics, for instances, would allow for a kettle put on the stove to freeze instead of boil, but if every atom in the universe were kettles on stoves, the probability of that happening in the next 50 billion years is still virtually zero.

 

[Cincinnatus]

1. I have read that "sperm can take up DNA" and that "new genetic and phenotypic features, unlinked to chromosomes, can thus be generated and inherited in a non-Mendelian ratio." Does this mean, or at least suggest, that the "selfish gene" is not the final arbiter of behaviour? Does any evidence (I'm thinking of investigations into inherited characteristics of rats and in the health and survival potential of children from stressed mothers) suggest a more Lamarckian view of "phenotypical power"?

2. Is it true that continental scientists are less interested in neo-darwinism than anglo-american biologists? If so, what theories do they favour?

3. Is it true that favourable mutations would soon be lost by interbreeding with non-mutated members of a species, that Darwin himself saw this as the biggest problem of his theory, and that neo-Darwinists have never convincingly solved it?

4. What is the survival value of looking up into the night and enjoying the starry sky?

5. I have read that mutations only occur at a rate of about one per several million cells in every generation, and that, since only a tiny number create beneficial traits which give a survival advantage, this is not fast enough to account for the extraordinary natural world, or for the rapidity that some species seem to change under environmental stress.

5. The consequence of a neo-darwinism is a non-altruistic, hierarchical and competitive world (cooperation only occurring between people likely to share the same genes). How can one explain the non-hierarchical, non-warlike and egalitarian behaviour of many hunter-gatherers, sedentary tribal people, and pre-ayrian cultures like Catal Huyuk, "Minoa" and the early Europeans described by Gimbutas and Campbell?

6. Pinker believes that we write poems and symphonies in order to achieve status. Does this effectively explain the behaviour and creations of artists?

7. Quantum physics is irrational, the neo-darwinist world is rational. Is there not a problem here? Why should the universe only exhibit irrational behaviour on the smallest scales? Is it not likely that if the fundamental units of existence are irrational that this might lead to irrational effects in the macro world - the kind of religious forces and experiences Dawkins dismisses out of hand (and I am not talking about the abrahamic religions here, which are easy targets, the only ones Dawkins aims at).

You claim to have read The Selfish Gene but the way these questions are phrased there is no way that you could have understood it. Here are my answers to your specific questions:

1. I have never heard of any mechanism by which sperm take up exogenous DNA (from where?). Please provide a reference for this.

2. The most highly visible disagreement in contemporary evolutionary theory has been between Dawkins, Dennet, Pinker etc (the adaptationists) and people like Steven J Gould and Richard Lewontin who are skeptical of adaptationist logic and prefer to emphasize the diversity of life as the raison d'etre for evolutionary theory. These are both Americans though, I'm not sure which continental theorists you might be thinking of.

3. No, this was indeed a problem with Darwin's original "blending" theory. This has not been an issue since the "modern synthesis" when we realized that independent segregation (cf. Gregor Mendel) was sufficient to explain why this is not a problem.

4. There is no survival value for looking up into the night sky. There may well be survival value in curiosity though.

5. See Dawkins' 1979 paper: "Twelve misunderstandings of kin selection" this is misunderstanding number 12.

6. No it does not. Why should evolution explain art?

7. Science is rational. This is an argument with science as a whole, not with evolutionary theory. If you reject the view that the world is rational then why are you asking questions about evolution at all?

 

[atyy]

1. I have never heard of any mechanism by which sperm take up exogenous DNA (from where?). Please provide a reference for this.

Smith K, Spadafora C.
Sperm-mediated gene transfer: applications and implications.
Bioessays. 2005 May;27(5):551-62.

Recent developments in studies of sperm-mediated gene transfer (SMGT) now provide solid ground for the notion that sperm cells can act as vectors for exogenous genetic sequences. A substantive body of evidence indicates that SMGT is potentially useable in animal transgenesis, but also suggests that the final fate of the exogenous sequences transferred by sperm is not always predictable. The analysis of SMGT-derived offspring has shown the existence of integrated foreign sequences in some cases, while in others stable modifications of the genome are difficult to detect. The appearance of SMGT-derived modified offspring on the one hand and, on the other hand, the rarity of actual modification of the genome, suggest inheritance as extrachromosomal structures. Several specific factors have been identified that mediate distinct steps in SMGT. Among those, a prominent role is played by an endogenous reverse transcriptase of retrotransposon origin. Mature spermatozoa are naturally protected against the intrusion of foreign nucleic acid molecules; however, particular environmental conditions, such as those occurring during human assisted reproduction, can abolish this protection. The possibility that sperm cells under these conditions carry genetic sequences affecting the integrity or identity of the host genome should be critically considered. These considerations further suggest the possibility that SMGT events may occasionally take place in nature, with profound implications for evolutionary processes. Copyright 2005 Wiley periodicals, Inc.

 

[dron]

No, this is not true, as observational evidence indicates. Of course, some mutations could become lost this way, but certainly not all of them.

What observational evidence? Do you mean the evidence that favourable mutations are clearly made it this far? Isn't this post-hoc reasoning? Any rate, why couldn't all, or at least most of the mutations be lost this way? Isn't it true that Darwin was troubled by this? I've read as much, but second hand, so I could be mistaken.

This is not a properly framed question (based upon what I believe you are attempting to imply). It would be similar to asking, "what is the survival value of not being able to breath under water?" In the later case, it evolved as a consequence of being able to breath better on land, and in the later, it likely was a consequence of greater intelligence and inquisitiveness, that had an important "survival value" for what should be obvious reasons.

Yes, I see that. Good answer. I don't agree that it was a consequence of intelligence and inquisitiveness, but I'm quibbling. Thank you.

I doubt that there is really a significant observational and theoretical basis for making such an a priori claim. As in everything, science is based on inductive logic, and this is what we learn from observing and testing the natural world, so any a priori claim such as the one you postulate is not going to be considered valid until it is shown to be true empirically.

Well I don't know. Not being a scientist I am unable to test cell mutation rate. All I can go on, is what I read. It's no more a priori than saying the population of London is ten million is it? I read that mutations occur one every million per generation. If this is incorrect, please point out my error.

Quantum physics is not "irrational". This is a false premise; it is akin to saying that cricket is "irrational" because the rules are different than baseball.

Hm. Yes, this could be a question of semantics. I have posted some questions in the physics sub form about this. I suppose QP is not irrational in your sense, but, as far as I understand the double-slit experiment, it "means" that elementary particles are behaving in a way that is impossible to imagine. I would call this irrational, in the same way I would call "infinity" irrational. We can give a symbol for infinity, and profitably put that symbol to use in equations and stuff, but we can't actually think of it, or imagine it. It's not just "weird" but outside of the brains' capacity to experience. I would suggest we have faculties that can experience it, but I wouldn't say it was the brain.

 

[Cincinnatus]

Oops, I see that your 7 questions were actually 8 questions. You had two #5s. My previous response was to your second #5 about altruism toward kin. I missed the first one. Though the first one has already been answered well by others in this thread anyway.

 

[dron]

1. I have never heard of any mechanism by which sperm take up exogenous DNA (from where?). Please provide a reference for this.

http://humrep.oxfordjournals.org/cgi/content/abstract/dem425v1"
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http://lib.bioinfo.pl/auth:Spadafora,C"

3. No, this was indeed a problem with Darwin's original "blending" theory. This has not been an issue since the "modern synthesis" when we realized that independent segregation (cf. Gregor Mendel) was sufficient to explain why this is not a problem.

Why is it not a problem? Sorry, I don't understand.

5. See Dawkins' 1979 paper: "Twelve misunderstandings of kin selection" this is misunderstanding number 12.

I will take a look at that and get back to you.

6. No it does not. Why should evolution explain art?

Well quite. Pinker seems to think it should though.

7. Science is rational. This is an argument with science as a whole, not with evolutionary theory. If you reject the view that the world is rational then why are you asking questions about evolution at all?

I don't reject the view that the world is rational, clearly it is, and clearly rational thinking is very useful. I am interested, amongst other things, in where rationality ends, and what it cannot explain.

 

[Cincinnatus]

Smith K, Spadafora C.
Sperm-mediated gene transfer: applications and implications.
Bioessays. 2005 May;27(5):551-62.

This sounds very interesting! Thanks for the reference... From reading that abstract though I doubt sperm-mediated gene transfer is a major player in evolution. They talk a lot about how it can be artificially induced to happen but at least in the abstract they don't claim to have a mechanism for how it might occur naturally... I'll actually read the paper when I have a chance though...

 

[Cincinnatus]

#6). With regard to Pinker's claim about artists and evolutionary theory, I've written quite a few posts on evolutionary psychology on this board. You may want to find those... It's probably best not to derail the conversation in this thread.

 

[atyy]

7. Quantum physics is irrational, the neo-darwinist world is rational. Is there not a problem here? Why should the universe only exhibit irrational behaviour on the smallest scales? Is it not likely that if the fundamental units of existence are irrational that this might lead to irrational effects in the macro world - the kind of religious forces and experiences Dawkins dismisses out of hand (and I am not talking about the abrahamic religions here, which are easy targets, the only ones Dawkins aims at).

Well, I'm not sure what you mean by "irrational" and "rational". I myself have never understood why science is supposed to be rational - I'm just happy if it predicts the future - like the sun rising tomorrow - though I hear solar system stability is an open mathematical problem. Anyway, the general question as to why laws on one scale appear to be very different from those at another is very interesting.

The best studied case is probably phase transitions at the critical point. Here the experimental data indicated that the critical exponents were the same for all sorts of different materials (of the same dimension) - and that the underlying differences in chemistry at a more "fundamental" level didn't show up at this "higher" level. How this could happen was explained by the "renormalization group" of Kenneth Wilson.

The philosophy then crept into elementary particle physics. Even Feynman thought he was discovering the fundamental laws of nature. Nowadays, many people consider the standard model to be just an "effective field theory".

To add more nonsensical questions to your question about why quantum mechanics doesn't show up in evolution (they don't even know why it doesn't show up in tennis!) - some questions I would like answered are:
Is CPT violation really not related to the 2nd law of thermodynamics?
Is Goedel's incompleteness theorem really irrelevant for calculus?

 

[dron]

I believe that quantum weirdness does show up in evolution, and tennis. It certainly shows up in my love life.

 

[atyy]

I believe that quantum weirdness does show up in evolution, and tennis. It certainly shows up in my love life.

How do you know it's quantum weirdness and not deterministic chaos?

 

[dron]

Evolution and tennis are life, and life, for me, is paradoxical, unthinkable and infinite. My love life is a simpler matter; my wife, along with a flask containing a poison, is currently in a sealed box shielded against environmentally induced quantum decoherence.

 

[Cincinnatus]

my wife, along with a flask containing a poison, is currently in a sealed box shielded against environmentally induced quantum decoherence.

:rofl::rofl::rofl:

 

[Mike H]

Late again, only chiming in with answers where I may have something to offer...

1.) Sperm-mediated gene transfer (SMGT) has been used in the development of transgenic organisms for about 20 years now, although I believe the phenomenon of SMGT was first observed a number of years prior in the 1970s. The vast majority of the studies are done via incubating sperm samples with DNA, although other methods are also used (liposomes, electroporation, and others). As I understand it, how frequently and to what extent it occurs in nature is still an open one, although it is suspected it may be of more relevance to some organisms than others. There's also been some investigation of the role of non-Mendelian inheritance in light of epigenetics (DNA methylation, histone modifications, and so on), but I'm not familiar with how that rigorously ties in with the modern evolutionary synthesis. (BTW, is that what you mean by neo-Darwinism?)

4.) It ties back to when our ancestors navigated by the stars to make it back to their cave with a cute blonde cavebabe tossed over their shoulder. (OK, I'm kidding here. But who knows? Heh.)

5a.) I am envisioning a potentially long discussion borne out of my response to this, but here it goes: mutation rates vary. See http://www.ncbi.nlm.nih.gov/books/bookres.fcgi/iga/ch15t3.gif for some representative ones of potential interest. For a good take on this topic in general which puts some of this question into slightly less abstract terms, see this really nice "back-of-the-envelope" calculation done here: http://sandwalk.blogspot.com/2007/07/mutation-rates.html

7.) I think the "bizzareness" of quantum physics can become slightly less disconcerting the more one spends time in its vicinity, although it never entirely goes away. I can remember the first time I ran an experiment as an undergraduate where I actually worked out what a certain set of experiments should look like based on the (relatively straightforward and simplified) quantum mechanics of the system of interest. It actually turned out to be the case! And the same thing - different system and questions, though - happened in grad school. It's no longer *as* weird, since it's no longer just working out laborious derivations or reading through lengthy explanations in a text/monograph - it's something which, given access to the right sort of lab and equipment/supplies, I could bring anyone I wished along, work out a (simple) derivation, and then do the experiment to see what we get. Then again, this may just be more a matter of it all seeming less abstract and more tangible. YMMV.

 

[dron]

Thank you Mike. Useful, interesting, and friendly post.

 

[Mike H]

You're welcome. Some additional commentary that may or may not be of interest...

1.) The review cited by atyy seems to square with what I knew about SMGT based on a skim-through - it's been used for quite a while in an applied context, but has yet to be really shown to occur naturally. There are certain cases where it might be more likely to occur (with aquatic organisms, given a proposed mechanism for SMGT), and it can't hurt to keep it in the back of one's mind when dealing with investigations that may involve it. Given the qualifiers mentioned in the review, it may operate at a level in nature where, when it does occur, it's not necessarily easily discernible from the background noise. Something neat, and definitely something of applied interest, but not nearly as major of an effect as it may seem based on press releases. Heh. Of course, even when it may occur, any offspring are still going to be subject to natural selection, so take that as you will. Speaking as someone who does not do evo-bio for a living (and therefore not familiar with all of the quantitative models floating out there), I would imagine that SMGT would need to be quantified in terms of its extent and frequency should it be shown to occur in nature before any conclusive statements could be made about its influence on evolutionary processes. I guess one could take limiting cases pretty easily, but I'll leave that for someone else to do...

7.) Finding out that's one intuition about how something works can fail when moving onto new frontiers should not come as much of a surprise if one thinks about it - it's happened to us all at a number of points, ranging from the trifling to the monumental. Typically, after some time, one develops an intuition about how things work in the new frontier and it's no longer as counter-intuitive or disconcerting. Discerning why one's original intuition failed can take some time, but eventually one (hopefully) figures it out. You may find the first set of slides here useful in gaining some understanding why our innate "classical physics" intuition misses a step when looking at quantum physics - it's relatively non-mathematical, although, given that these are intended to accompany a lecture, one can only safely say so much based on just these slides.