A Discussion of Evolutionary Theory

[heretic888]

Recently, Loki began a thread concerning a discussion of sociobiologist Richard Dawkins' theories presented in the book, The Selfish Gene. This prompted me to do a little bit of research concerning the ideas of Mr. Dawkins, particularly the position he refers to as "Universal Darwinism".

Sometime later, I came across a recent issue of Time magazine in which an in-depth cover story highlighting the "debate" between Darwinism and Intelligent Design was covered. While I don't buy into Intelligent Design myself (nor its mentally-handicapped cousin Creationism), I did find some of the critiques its proponents leveled at traditional Darwinism (or, neo-Darwinism really) to be intriguing.

This prompted me to do a bit of research on my own, and I came across a string of theories and ideas that are collectively referred to as post-Darwinism. Many of these ideas focus on things like: constraints on evolution that lead to "directional" patterns of development, the inability of random variation and natural selection to adequately explain macroevolution, instances of genetic "staltation" that occur during development between species (subsequently making the evolutionary Tree of Life more like a Net of Life), self-organization theories that result in developmental hierarchies of increasing complexity, and neo-Lamarckian ideas that organisms can in some instances "select" adaptations for their own environment (this fits in somewhat with multilevel selection and has been demonstrated by E. Coli strands and, arguably, by human beings).

I realize that much of these theories are held by a minority (albeit a vocal minority) within the scientific community. However, they seem to be largely supported by evidence (albeit not always conclusive) and don't discount natural selection so much as complementing it within a larger theoretical framework. Not having a particularly strong background in biology myself, I find post-Darwinism to be far more compelling than the mainstream neo-Darwinism taught in most schools today. It also seems to fit more fluidly with the process theology of Alfred North Whitehead and integral philosophy of Ken Wilber (as well as traditional Hegelian philosophy), all of which I have some affinity for.

So, my question to all of you is what is your position regarding the state of evolutionary theory? I think any rational person that has reviewed the data would have to come to the conclusion that evolutionary adaptation of some kind is a reality. At the same time, however, there seems to be some disagreement on the exact mechanisms of evolution.

What do you think??

 

[Loki]

Bet ya' didn't expect to see me here, did ya'... :uhyeah:

Like you, I don't have a very strong background in biology either, so most of what you just brought up might as well have been hieroglyphics. Could you provide some links to these critiques?

The points can muster some kind of opinion on I will reply to:

What are the cases where natural selection and random variation can't explain macroevolution? I recently heard this as a theistic argument against it, but could you have meant "prove" rather than "explain"? That's what the argument did, and promtly concluded that if natural selection can't prove macroevolution, it must be God. Sheesh.

Another point is that evolution is, like you say, effectively fact. It's the mechanism which is in dispute. An interesting article on it can be found here:

http://www.talkorigins.org/faqs/evolution-fact.html

Like many others said, Dawkins is very convincing, so I'm going with his view until presented with data to the contrary.

 

[KenpoEMT]

Sometime later, I came across a recent issue of Time magazine in which an in-depth cover story highlighting the "debate" between Darwinism and Intelligent Design was covered. While I don't buy into Intelligent Design myself, I did find some of the critiques its proponents leveled at traditional Darwinism (or, neo-Darwinism really) to be intriguing.

constraints on evolution that lead to "directional" patterns of development, the inability of random variation and natural selection to adequately explain macroevolution, instances of genetic "staltation" that occur during development between species (subsequently making the evolutionary Tree of Life more like a Net of Life), self-organization theories that result in developmental hierarchies of increasing complexity, and neo-Lamarckian ideas that organisms can in some instances "select" adaptations for their own environment (this fits in somewhat with multilevel selection and has been demonstrated by E. Coli strands and, arguably, by human beings).

However, they seem to be largely supported by evidence (albeit not always conclusive) and don't discount natural selection so much as complementing it within a larger theoretical framework. Not having a particularly strong background in biology myself, I find post-Darwinism to be far more compelling than the mainstream neo-Darwinism taught in most schools today. It also seems to fit more fluidly with the process theology of Alfred North Whitehead and integral philosophy of Ken Wilber (as well as traditional Hegelian philosophy), all of which I have some affinity for.

So, my question to all of you is what is your position regarding the state of evolutionary theory? I think any rational person that has reviewed the data would have to come to the conclusion that evolutionary adaptation of some kind is a reality. At the same time, however, there seems to be some disagreement on the exact mechanisms of evolution.

What do you think??

hmmm...

The study of Ultimate Causes is frought with difficulties. The path of Evolution cannot be determined with any sort of mathematical certainty. It cannot be done. Therefore, there cannot be any predetermination of sorting variations.

I am fairly sure that it is a mistake to use the word "theory" when contemplating Evolutionary Science. That's just my opinion. The Ph.D.s know what they are doing (I hope!). A hypothesis that sits on top of the heap doesn't qualify as a theory. Evolution cannot be analyzed in a lab. IMHO, mistakes are too easily made using comparison.

I think that alot of the "new evolution" schools of thought are made up of concepts that merely fill in what their creators think of as 'the holes left by Darwin,' and that is why they remain in the minority (IMO). Anyone can create a new phylogeny that dipicts whatever they want, and it becomes a problem when we are left with only comparitive methods to determine what is most correct.

I have serious reservations about "neo-lamarckian" ideas simply because they bring up Lamarck. Transformationalism has been fully discredited by the modern study of genetics. I am not at all familiar with this neo-lamarckism; however, I love to kick around new ideas just to see what they will yield. Maybe I hold inaccurate viewpoints in one or more areas. I am not afraid to see what is "out there."

At this point in time, my opinion of Darwinism is that it is a useful educational tool...

I am hardly an expert, but I would love to debate some of the various aspects of evolution and neo-evolutionary ideas. We might come up with something interesting.

 

[Loki]

I am fairly sure that it is a mistake to use the word "theory" when contemplating Evolutionary Science. That's just my opinion. The Ph.D.s know what they are doing (I hope!). A hypothesis that sits on top of the heap doesn't qualify as a theory. Evolution cannot be analyzed in a lab. IMHO, mistakes are too easily made using comparison.

Actually, evolution has been studied in a lab. I'll look up the exact exmple and get back to you.

I think that alot of the "new evolution" schools of thought are made up of concepts that merely fill in what their creators think of as 'the holes left by Darwin,' and that is why they remain in the minority (IMO). Anyone can create a new phylogeny that dipicts whatever they want, and it becomes a problem when we are left with only comparitive methods to determine what is most correct.

That's the feeling I get too, but if someone else has contradictory evidence, a better theory or any conflicting with Darwin, I'm willing to listen.

 

[KenpoEMT]

Actually, evolution has been studied in a lab. I'll look up the exact exmple and get back to you.

Well, unless it is a multi-million year study... :lol:

I know that there are some limited examples of microevolution that can be studied (like the moths in England), but as far as the 'big picture'...I just can't see how.

*patiently awaiting the link*

I'm willing to listen.

Me too. This has the potential to become a darn good thread.

 

[Loki]

Well, unless it is a multi-million year study... :lol:

I know that there are some limited examples of microevolution that can be studied (like the moths in England), but as far as the 'big picture'...I just can't see how.

*patiently awaiting the link*

Then we have misunderstanding. When you said "evolution cannot be analyzed in a lab", I thought you were referring to all evolution.

How one would actually empirically prove macroevolution without such a study eludes me, but lacking such proof doesn't mean it's wrong.

 

[goshawk]

Hey, a (thus-far) intelligent, non-feces-flinging thread on evolution. I'm impressed. ::grin::

As far as I'm concerned, Intelligent Design is complete BS, never mind "Creationism". The body of evidence and number of scientific studies backing up the theory of evolution is far too great to ignore in the name of theology.

The biggest peeve I have with the common understanding of evolution these days (even from proponents of evolution theory) is the vaguely Lamarckian idea that "this trait was the best, so it got selected to survive", which is almost correct but not quite. Selection is a negative process, not a positive one; simply, the traits that don't survive die out, and the ones that survive don't die out.

This means that occasionally really stupid, inefficient or redundant features survive the process of selection; for example, all the back- and shoulder- problems we suffer due to being poorly designed for an upright posture are unlikely to go away through evolution--the current level of civilization we've realized as a species means that they're not likely to kill us before we procreate. And that, right there, is the bottom line; if the trait is able/likely to breed, it will be passed on. If it negatively affects the individual's reproductive success, it's a dead trait walking, so to speak.

I can't tell you how many times I went through that in my Anthropology class. =| It's definitely a point of severe irritation for me. However, I find that quite a few people who never understood that become much more open-minded towards evolution after it's been adequately explained.

As to all the little bare patches and gaps in the theory...well, it's not like we've reached the pinnacle of scientific understanding. Who knows, maybe in fifty years they'll be looking back and laughing at us silly Darwinists like we laugh at the Heliocentric view of the universe. ::shrug:: Meantime, evolution's the best we've got.

 

[Blindside]

Interesting article on a possible new species that seems to have been generated from hybridization:

http://www.newscientist.com/channel/life/evolution/dn7741

Lamont

 

[KenpoEMT]

Then we have misunderstanding. When you said "evolution cannot be analyzed in a lab", I thought you were referring to all evolution.

Well, differential survival and reproduction amoung members of a given population certainly can be studied. You are absolutely correct in your assertation that microevolution can be directly observed to a limited degree; however, Gradualism states that said variations occur over millions of years. We can only see a snap-shot picture of these adaptations. Whether or not they will persist is unknown.

How one would actually empirically prove macroevolution without such a study eludes me, but lacking such proof doesn't mean it's wrong.

Yeah, that's exactly what I say. If it cannot be demonstrated, it is not a theory. It's barely more than a hypothesis.
Comparative analysis does not impress me when it comes to determining orgins, but it is all we can use at this point in time.

This means that occasionally really stupid, inefficient or redundant features survive the process of selection

Yes, like my ex-wife :lol:

 

[Loki]

Hey, a (thus-far) intelligent, non-feces-flinging thread on evolution. I'm impressed. ::grin::

*puts down bucket of feces*

Damnit goshawk... do you have any idea the amount of monet I spent on laxitives?

As far as I'm concerned, Intelligent Design is complete BS, never mind "Creationism". The body of evidence and number of scientific studies backing up the theory of evolution is far too great to ignore in the name of theology.

The biggest peeve I have with the common understanding of evolution these days (even from proponents of evolution theory) is the vaguely Lamarckian idea that "this trait was the best, so it got selected to survive", which is almost correct but not quite. Selection is a negative process, not a positive one; simply, the traits that don't survive die out, and the ones that survive don't die out.

This means that occasionally really stupid, inefficient or redundant features survive the process of selection; for example, all the back- and shoulder- problems we suffer due to being poorly designed for an upright posture are unlikely to go away through evolution--the current level of civilization we've realized as a species means that they're not likely to kill us before we procreate. And that, right there, is the bottom line; if the trait is able/likely to breed, it will be passed on. If it negatively affects the individual's reproductive success, it's a dead trait walking, so to speak.

I can't tell you how many times I went through that in my Anthropology class. =| It's definitely a point of severe irritation for me. However, I find that quite a few people who never understood that become much more open-minded towards evolution after it's been adequately explained.

As to all the little bare patches and gaps in the theory...well, it's not like we've reached the pinnacle of scientific understanding. Who knows, maybe in fifty years they'll be looking back and laughing at us silly Darwinists like we laugh at the Heliocentric view of the universe. ::shrug:: Meantime, evolution's the best we've got.

Lamarck's concept of inheritance of acquired traits is not only not proven, it's been disproven by genetics.

Yup, and in addition to back problems we have junk DNA and lethal genes, an excellent reason to avoid incest if I've ever heard one.

 

[KenpoEMT]

Yup, and in addition to back problems we have junk DNA and lethal genes, an excellent reason to avoid incest if I've ever heard one.

Well, that and the fact that incest is, you know...yucky.

 

[Makalakumu]

So, my question to all of you is what is your position regarding the state of evolutionary theory?

As a person who is somewhat learned in this stuff, I'll hedge my bets with evolution. I think that evolution, as a process, is the dominant factor in our lives. Good evidence exists that shows that evolution shaped our phylogeny. More evidence exists that shows that evolution shaped our minds.

The conflict is in the details...and I'm not sure which to discuss. We could talk about positive selection pressures, negative selection pressures, sexual selection pressures, Human Endogenic Retro Viruses...etc. We probably should pick one and focus...

Or we could just discuss various questions...such as the studying of macroevolution. This can be studied in the lab. One of my Professors has four species of plesiosaurs ranging from 120mya to 70 mya. One can compare the differences between the plesiosaurs species and correlate them with stratigraphic/paleoenvironmental data. One can clearly see that as the environment changed, so did the plesiosaur...in fact, sometimes massive changes occured. This study occured in a lab.

Also, at the University of Chicago, one can do a similar study with whales and their ancestors. If taking a four legged land dwelling predator and changing it into a "fish" isn't macroevolution, I don't know what is.

 

[Loki]

As a person who is somewhat learned in this stuff, I'll hedge my bets with evolution. I think that evolution, as a process, is the dominant factor in our lives. Good evidence exists that shows that evolution shaped our phylogeny. More evidence exists that shows that evolution shaped our minds.

The conflict is in the details...and I'm not sure which to discuss. We could talk about positive selection pressures, negative selection pressures, sexual selection pressures, Human Endogenic Retro Viruses...etc. We probably should pick one and focus...

Or we could just discuss various questions...such as the studying of macroevolution. This can be studied in the lab. One of my Professors has four species of plesiosaurs ranging from 120mya to 70 mya. One can compare the differences between the plesiosaurs species and correlate them with stratigraphic/paleoenvironmental data. One can clearly see that as the environment changed, so did the plesiosaur...in fact, sometimes massive changes occured. This study occured in a lab.

Also, at the University of Chicago, one can do a similar study with whales and their ancestors. If taking a four legged land dwelling predator and changing it into a "fish" isn't macroevolution, I don't know what is.

Really interesting stuff you got there. Has your professor gone public with this? And if so, why isn't this acknowledged as proof for macroevolution.

The land-dweller became a fish? I always though it was the other way around.

 

[Makalakumu]

The plesiosaur study is a very common study. It has been done with many many other types of ancient animals...humans and their ancestors being the most famous example.

Turning a four legged predator into a "fish" was a cutsy way of saying "like a fish." Whales are mammals and breath air, but they kinda look like fish.

As far as geochronology is concerned, land was first invaded by the sea...

 

[KenpoEMT]

Sure, the comparative method can be used in a lab...or in your living room.


You cannot test macroevolution in a laboratory. Generally speaking, experiments conducted in a laboratory require controls. What kind of control is available for studying evolution? Testing macroevolution and observing the results against contols CANNOT be done in a laboratory. The comparative method and the experimental method are two different animals. The comparative method isn't something that I would hang my hat on.

Here's an example: The Brontosaurus never really existed. We've known that since the 1800's. On how many phylogenies do you see Brontasaurus? Marsh made a mistake. It is not hard to find mistakes in comparative studies.
...and how about Cope and Platyurus?

There are many, many examples of honest mistakes and outright fraud.

You are basically accepting nothing more than an educated guess (and sometimes an educated deception).

Without observable and testable data, it becomes very difficult to recognize even the simplest mistake.

 

[Makalakumu]

An experiment is one form of verification in the scientific method. Some "experiments" do not have the classical test tube look, but it does not negate their power.

In fact, you take drugs that depend on this power. Some biologic cannot be created in the laboratory. Protein folding, for instance, is too complex to be recreated in the laboratory. The only studies that can even begin to probe its depths, are comparative analysis.

As far as controls go, they are there, but in many cases are theoretical. When the bones are in front of you, there isn't really much to control. In other comparative experiments, more concrete controls can be established.

Macroevolution can and has been studied in the lab. Thousands of examples have been verified.

 

[heretic888]

Wow. I didn't expect this many posts in such a short time. I guess this is a hot topic for a lot of people.

To address some querries brought up:

1) Before anyone gets any misunderstandings here, I am not disputing the reality of evolution nor am I basing my critiques on a theistic argument. In fact, as I've demonstrated abundantly in the past, in no way am I a 'theist' in the traditional sense (panentheist, maybe).

2) While I am interested in disussing the philosophical as well as biological aspects of evolutionary theory, this isn't really meant to be a discussion of 'Ultimate Causes'. I personally believe in a type of neo-Hegelian spiritual progression (and post-Darwinism fits in nicely with this), but I don't feel it is necessary (nor prudent) to base critiques of biological theories on such beliefs.

2) A large part of the critiques of neo-Darwinism is that it is assumed a priori that random variation and natural selection produce macroevolutionary changes or even Stephen Jay Gould's punctuated evolution. Pointing out changes in the environment that occured co-temporaneously with changes in a species is correlation, not causation. The debate is to whether other mechanisms (such as self-organization theories or virogenetic "staltation") can more adequately explain macroevolutonary changes. A large part of this also revolves around the existence of transitional forms between species (some of the post-Darwinist ideas effectively rule out the need for transitional forms, making the arguments of Intelligent Design proponents void).

3) Please note that just because Lamarckism has been ruled out does not mean the same can be said of neo-Lamarckism. Darwinism (as in, what Darwin actually said in totality) has also been thoroughly discredited. However, neo-Darwinism (the so-called "synthetic model" which combines some principles of Darwinism with Mendelian genetics and inceased knowledge of things like geography, chemistry, and so forth) is now widely accepted in academic circles. Part of the argument here is that neo-Darwinism is to post-Darwinism what Darwinism is to neo-Darwinism (i.e., one does not rebuff the other, but merely puts it in a broader theoretical context).

4) It should be noted that just because something is currently in the minority in science does not mean it is ill-founded. In much the same way, theories revolving around post-formal stages of cognitive development are in the minority in developmental psychology. But, this is by and large because the field is so relatively young (both post-Darwinism and neo-Piagetianism have only presented positive evidence within the past 20 years or so). My speculation is that both sets of theories will gain increasing acceptance over the next few decades, up to the point where the minority becomes the majority.

5) With all due respect to Dr. Dawkins, the ideas espoused in The Selfish Gene are based upon research that is now well over 30 years old (which probably used technology much older than this). When asked about post-Darwinism on a Q & A forum, Dawkins had no idea what the questioner was talking about and thought it was the same thing as neo-Darwinism. His theory of gene-centrism, as well as what he calls Universal Darwinism, are not particularly popular these days (from what I can tell, anyway). Even the talkorigins.org site is somewhat critical of them.

6) Its all well and good to say that "evolution shaped our minds", but be careful not to stray into the speculative claims made by evolutionary psychology. Of course, evolutionary psychology assumes a type of Universal Darwinism itself, which is probably a large part of its problem (along with the whole general lack of direct research thing).

In my next few posts, I'll try to fish up some of the links regarding the claims of post-Darwinism. Laterz.

 

[Makalakumu]

Here is a good primer on Evolutionary Psychology. This field, I believe, is in its infancy. However, the assertion that there is no research to back its claims is incorrect.

 

[Makalakumu]

Here is a nice little list of transitional fossils that have been found.

http://www.talkorigins.org/faqs/faq-transitional.html

 

[heretic888]

Interesting article on a possible new species that seems to have been generated from hybridization:

http://www.newscientist.com/channel/life/evolution/dn7741

Ironically, cases such as these are one such example of some post-Darwinian principles in action.