“work on evo-devo shows that not only are evolutionary relationships evident when comparing the development of different organisms, but there exists a genetic mechanism for these relationships in the modulation of the Hox genes.”
Indeed.
Just as development is the unfolding of an algorithm that is already present in the zygote at the time of fertilization, so evolution is the unfolding of an algorithm that was already present at a time before evolution began.
In addition, just as a mature adult represents the culmination of this developmental algorithm, so the present state of life on earth represents the culmination of the evolutionary algorithm and no further evolution can be expected.
We know the immediate origin of the developmental algorithm, it was inherited from the previous generation. But the question of where this information originally came from remains unanswered. In evolution, one would be wise to suspect that this algorithm has a long history, and probably did not originate on the earth, but came to earth from elsewhere, fully front-loaded to unfold in a compatible environment into the biosphere we see today.
wambasays
So Evo-Devo has nothing to do with wearing lampshade hats and playing New Wave music?
Sean Foleysays
So Evo-Devo has nothing to do with wearing lampshade hats and playing New Wave music?
I suppose you could argue that examinations of the tail bud in human embryos are a case of the ape regarding his tail. Other than that, you’re right: evo-devo folks have done little to twist away the gates of steel.
[quote]so the present state of life on earth represents the culmination of the evolutionary algorithm and no further evolution can be expected.[/quote]
That’s rather self-centred, isn’t it? The way I see it, we’re just paving the way for the next rulers of Earth – the rats.
“That’s rather self-centred, isn’t it? The way I see it, we’re just paving the way for the next rulers of Earth – the rats.”
The pattern over the last few million years has been a pattern of extinction. At the end of the day, those best adapted will survive and the others will fall into the dustbin of history. If it’s the rats or the cockroaches, so be it.
It’s almost like this is an experiment in survival. Seed the earth with an algorithm that produces many different forms and then sit back and see which ones make it to the end.
Torbjorn Larssonsays
“the present state of life on earth represents the culmination of the evolutionary algorithm and no further evolution can be expected.”
http://loom.corante.com/archives/2006/03/08/this_week_in_human_evolution.php :
“A new paper presents the results of a systematic scan for human genes that have experienced natural selection in the past few thousand years. An impressive 700 regions turned up.” … “there are other brain genes that the new study identifies as evolving.”
Apparently Charlie will not partake in the ongoing evolution of the human brain. No surprise there.
CCPsays
?!
Charlie Wagner = (a somewhat less irascible) John A. Davison ?!!
…though “The Davisonian Inquisition” just doesn’t have the same ring to it…
haploteuthis feroxsays
Serious question, not trying to start rants from torch wielding kooks:
Is Homo Sapiens still evolving, at least in a way that Darwin would recognize? With the advent of modern medicine, fertility drugs, etc. the reproductive success of any particular individual is far less constrained by their initial genetic make-up than it once was. Reproductive success is now more a matter of social status (accessibility to healthcare, good diet, etc.) than it is inborn physical fitness
As Kate Campbell sings: “Evolution’s almost through, there ain’t much left that we can’t do. Seems like a paradox, you can’t grow corn in a box. Still can’t grow corn in a box” (“Corn in a Box” from the album “Momnuments”)
Markksays
“Is Homo Sapiens still evolving?”
Of course IMHO, if Homo Sapiens still exists even 500,000 years from now and we look at the genetic profile I am confident it will be quite different then today, take 5,000,000 years and if we are still alive it will be correspondingly (strikingly) different.
People who ask if evolution is still working on H.Sapiens must assume an incredibly stable environment for a long time. Just because some people live and have children and didn’t before – all that is doing is adding another factor into selection – not stopping it. If we look at the movie of Homo Sapiens from our individual time scale it may look like we are stuck on a frame, but it doesn’t mean the movie has stopped.
Primordial Oozesays
ferox,
Medicine is, in fact, allowing for evolution that has previously been constrained. Caesarean sections are allowing us to increase the size of our skulls, and brains, by relaxing the cranial/pelvic disproportion limitation. We’ll soon have the capability to believe that we are 10% more clever than ever before.
Reproductive success is a matter of religious doctrine and lack of any sense of responsibility more than social status, I would argue…
(Disclaimer, I have two children, and thus a fitness of 1)
bmurraysays
ferox, while we are certainly active in changing our own environment, and therefore the target for our fitness solution, we have by no means reduced that fitness solution to “all genotypes”. And that environment has always been changing, though now we’re are opening up territory that was previously impossible. The next few hundred thousand years ought to be pretty interesting, provided we manage to sustain our hold on our environment. Otherwise same old same old. Cambrian explosion, yawn. :D
Haploteuthis feroxsays
Ooze,
I meant “social status” in the broadest possible sense – as a social animal living in a cooperative, technological society, not just “social” as in economic condition or placement.
But to say that medicine is allowing for evolution that has previously been constrained, means that a baby born with a skull that would have killed both fetus and woman during childbirth in 300 BC will now survive and have a better chance at passing on the “big skull” gene* (*I know this is a gross oversimplification). But having a big skull doesn’t neccessarily INCREASE reproductive success (even *if* it does mean an increase in intelligence – just ask any of us that were in Chess Club). So there will be more big skulls, but the environment isn’t selecting for big skulls, so is this really evolution?
And contrary wise, there are people reproducing today that would have never made it to puberty 200 years ago.
I keep picturing that old Outer Limits where David MacCallum “evolved” thousands of years and got a big head.
BMurraysays
ferox, there are other selection pressures of the modern world that are new, however. Consider the reduced population growth in industrialized nations, the new pressures on sexual selection from mass media portrayals of what sexuality is, and the impact of private motor vehicle ownership on the breeding potential of 16 year olds.
As a matter of fact, I was wondering about that. Just one thing I’m curious about: What happens to the term “embryology”? I noticed Zachary uses the word “embryological” in the post, but the field is referred to as developmental biology. Is the term embryology still used? Is there any difference between embryology and developmental biology?
lt.kizhesays
….the new pressures on sexual selection from mass media portrayals of what sexuality is, and the impact of private motor vehicle ownership on the breeding potential of 16 year olds
But modulate that heavily by the decoupling of sexuality from reproduction, due to effective contraception. The highest fitness (in the West) is not likely to be among those who have the most sex, it’s those who either choose to have (more than the average number of) children, or fail to practice half-way reliable birth control. Whether that correlates with anything genetic, I dunno (and quite possibly no one does).
At last something Charlie Wagner and I can agree on! He wrote:
“Just as development is the unfolding of an algorithm that is already present in the zygote at the time of fertilization, so evolution is the unfolding of an algorithm that was already present at a time before evolution began.”
The algorithm is called natural selection and, yes, it was present right before evolution began.
lt.kizhe asked: “What happens to the term “embryology”? I noticed Zachary uses the word “embryological” in the post, but the field is referred to as developmental biology. Is the term embryology still used? Is there any difference between embryology and developmental biology?”
Mostly it’s just a more fashionable name for the same thing (although one could argue that development also refers to processes and events that occur outside embryonic stages, such as larvae). For example, in the late 1980s one of the main specialist journals in the field changed its name from “Journal of Embryology and Experimental Morphology” to the much more elegant “Development”. Interestingly, Darwin used the word “development” to mean evolution.
“The algorithm is called natural selection and, yes, it was present right before evolution began.”
Natural selection is not an algorithmic process. An algorithm is a mathematical equation or a set of instructions in a program. It is a step by step procedure for solving a problem and it always requires intelligent input. It is necessary to define the problem and then state the specific set of instructions to solve it.
In addition, natural selection is not evolution. Evolution is the emergence of highly organized structures, processes and systems, where they did not exist before.
Only intelligence can recognize a problem, define that problem and create a series of instructions to solve it.
The homeobox contains a set of instructions for determining how the genes are expressed during development.
A more global algorithm determines which genes are turned on and in what order to effect the emergence of the highly organized structures, processes and systems that are necessary to sustain life. No such algorithm ever created itself from nothing. No combination of accidental mutations, recombinations or changes in gene frequency could have accomplished this task.
So Charlie Wagner and I don’t agree after all… What a surprise! He said: “Natural selection is not an algorithmic process. An algorithm is a mathematical equation or a set of instructions in a program. It is a step by step procedure for solving a problem and it always requires intelligent input. It is necessary to define the problem and then state the specific set of instructions to solve it.”
Under your definition of algorithm development wouldn’t count as one either, so you can’t have it both ways. On the algorithmic nature of natural selection I agree with Dennett and Dawkins and others. But that’s not really important. Calling it an algorithm is only an analogy, a way to clarify it’s operation. But the concept of natural selection is clear and precise enough not to need these analogies, unlike much of what you write on evolution.
“A more global algorithm determines which genes are turned on and in what order to effect the emergence of the highly organized structures, processes and systems that are necessary to sustain life.”
See, I have no idea what any of that means. Now try to explain it without analogies…
mantissays
A more extensive explanation can be found in Sean Carroll’s Endless Forms Most Beautiful. Carroll does a good job of writing a book for what I will call the educated layman. I’m about 2/3s of the way through it (part of my um, required reading in preparation for my master’s thesis) and as a non-physical scientist I think it finds a balance in providing in-depth details without being esoteric. These posts and books are definitely worth promoting, as so many creationist attacks on evolution seem based on an assumption that evolution is some sort of fixed science. They attack “gaps” or “flaws” in evolutionary theory as if the scientific inquiry had stopped and everyone was happy with the level of knowledge about evolution. It’s absurd of course, but the way to combat it seems to be by highlighting recent developments of the theory in various areas, and Evo Devo is a great example of how evolutionary theory within different fields comes together so nicely, and how thinking about the science in different ways provides new insight. Science will fill the gaps, not superstition.
Torbjorn Larssonsays
“An algorithm is a mathematical equation or a set of instructions in a program.”
That’s wrong. An algorithm is a procedure (a finite set of well-defined instructions) for accomplishing some task which, given an initial state, will terminate in a defined end-state.
Evolution is such a procedure. It’s easiest to see if you confine yourself to RM+NS and follow a couple of generations under selective pressure. (In this case the algorithm repeats indefinitely.) There is nothing here that says the abstract instructions are manmade; here they are concretised by mutations and selective cullings.
“It is a step by step procedure for solving a problem and it always requires intelligent input.”
So this is wrong; you haven’t grasped the abstract concept of an algorithm.
You can concretize the abstract concept in several ways. One of them is to make computer software. It’s called genetic algorithms and they behave exactly as RM+NS in nature. This demonstrates both the abstraction and the concretisation nicely, unless you are a dunze.
“In addition, natural selection is not evolution.”
Not by itself, there are several mechanisms involved; but you should know this by now.
“Evolution is the emergence of highly organized structures, processes and systems, where they did not exist before.”
This is wrong too (surprise, surprise), evolution as adaption can go to simpler systems. Organisation isn’t the goal of the game, survival is, remember?
“Only intelligence can recognize a problem, define that problem and create a series of instructions to solve it.”
This is wrong since evolution is a disproof. If you contest that you have to _first_ prove that evolution was ID, of course! What were you thinking of (or with)?
Caledoniansays
The evolutionary process does not result in a predefined end-state in finite time. It’s not an algorithm.
The fact that Wagner is right about this point does not prevent his other points from being complete junk. Please stop opposing everything he says and oppose only the incorrect things — the sets are almost identical, so I don’t think a little restraint is impossible.
“The evolutionary process does not result in a predefined end-state in finite time. It’s not an algorithm.”
I think you are missing the point on three accounts.
First, if you follow a couple of generations they will result in a predefined end-state; they will be better adapted to the current selective pressure. It’s merely that the algorithm repeats indefinitely (and the selective pressures changes et cetera). This isn’t an unusual thing; many softwares are such, for example the one that checks out the current position of your mouse. (Technically the hardware issues an interrupt when you move the mouse; but the point is that the particular hardware/software action is infinitely repeating.)
Second, that definition I gave is an abstract one. Perhaps there (must) exist some exact definition in computer science. In real life, it’s usually enough to see if you can make some graph of it, or a precise list with precise steps, that lets you, hardware or software perform the actions. If you can do it for real from the abstract definition and it performs some desired task, it’s an algorithm.
Third, there already exists softwares with genetic algorithms. You can find examples on the web, download and play around with them yourself.
My reply to Zachary
Zachary Moore wrote:
“work on evo-devo shows that not only are evolutionary relationships evident when comparing the development of different organisms, but there exists a genetic mechanism for these relationships in the modulation of the Hox genes.”
Indeed.
Just as development is the unfolding of an algorithm that is already present in the zygote at the time of fertilization, so evolution is the unfolding of an algorithm that was already present at a time before evolution began.
In addition, just as a mature adult represents the culmination of this developmental algorithm, so the present state of life on earth represents the culmination of the evolutionary algorithm and no further evolution can be expected.
We know the immediate origin of the developmental algorithm, it was inherited from the previous generation. But the question of where this information originally came from remains unanswered. In evolution, one would be wise to suspect that this algorithm has a long history, and probably did not originate on the earth, but came to earth from elsewhere, fully front-loaded to unfold in a compatible environment into the biosphere we see today.
So Evo-Devo has nothing to do with wearing lampshade hats and playing New Wave music?
So Evo-Devo has nothing to do with wearing lampshade hats and playing New Wave music?
I suppose you could argue that examinations of the tail bud in human embryos are a case of the ape regarding his tail. Other than that, you’re right: evo-devo folks have done little to twist away the gates of steel.
[quote]so the present state of life on earth represents the culmination of the evolutionary algorithm and no further evolution can be expected.[/quote]
That’s rather self-centred, isn’t it? The way I see it, we’re just paving the way for the next rulers of Earth – the rats.
Corkscrew wrote:
“That’s rather self-centred, isn’t it? The way I see it, we’re just paving the way for the next rulers of Earth – the rats.”
The pattern over the last few million years has been a pattern of extinction. At the end of the day, those best adapted will survive and the others will fall into the dustbin of history. If it’s the rats or the cockroaches, so be it.
It’s almost like this is an experiment in survival. Seed the earth with an algorithm that produces many different forms and then sit back and see which ones make it to the end.
“the present state of life on earth represents the culmination of the evolutionary algorithm and no further evolution can be expected.”
http://loom.corante.com/archives/2006/03/08/this_week_in_human_evolution.php :
“A new paper presents the results of a systematic scan for human genes that have experienced natural selection in the past few thousand years. An impressive 700 regions turned up.” … “there are other brain genes that the new study identifies as evolving.”
Apparently Charlie will not partake in the ongoing evolution of the human brain. No surprise there.
?!
Charlie Wagner = (a somewhat less irascible) John A. Davison ?!!
…though “The Davisonian Inquisition” just doesn’t have the same ring to it…
Serious question, not trying to start rants from torch wielding kooks:
Is Homo Sapiens still evolving, at least in a way that Darwin would recognize? With the advent of modern medicine, fertility drugs, etc. the reproductive success of any particular individual is far less constrained by their initial genetic make-up than it once was. Reproductive success is now more a matter of social status (accessibility to healthcare, good diet, etc.) than it is inborn physical fitness
As Kate Campbell sings: “Evolution’s almost through, there ain’t much left that we can’t do. Seems like a paradox, you can’t grow corn in a box. Still can’t grow corn in a box” (“Corn in a Box” from the album “Momnuments”)
“Is Homo Sapiens still evolving?”
Of course IMHO, if Homo Sapiens still exists even 500,000 years from now and we look at the genetic profile I am confident it will be quite different then today, take 5,000,000 years and if we are still alive it will be correspondingly (strikingly) different.
People who ask if evolution is still working on H.Sapiens must assume an incredibly stable environment for a long time. Just because some people live and have children and didn’t before – all that is doing is adding another factor into selection – not stopping it. If we look at the movie of Homo Sapiens from our individual time scale it may look like we are stuck on a frame, but it doesn’t mean the movie has stopped.
ferox,
Medicine is, in fact, allowing for evolution that has previously been constrained. Caesarean sections are allowing us to increase the size of our skulls, and brains, by relaxing the cranial/pelvic disproportion limitation. We’ll soon have the capability to believe that we are 10% more clever than ever before.
Reproductive success is a matter of religious doctrine and lack of any sense of responsibility more than social status, I would argue…
(Disclaimer, I have two children, and thus a fitness of 1)
ferox, while we are certainly active in changing our own environment, and therefore the target for our fitness solution, we have by no means reduced that fitness solution to “all genotypes”. And that environment has always been changing, though now we’re are opening up territory that was previously impossible. The next few hundred thousand years ought to be pretty interesting, provided we manage to sustain our hold on our environment. Otherwise same old same old. Cambrian explosion, yawn. :D
Ooze,
I meant “social status” in the broadest possible sense – as a social animal living in a cooperative, technological society, not just “social” as in economic condition or placement.
But to say that medicine is allowing for evolution that has previously been constrained, means that a baby born with a skull that would have killed both fetus and woman during childbirth in 300 BC will now survive and have a better chance at passing on the “big skull” gene* (*I know this is a gross oversimplification). But having a big skull doesn’t neccessarily INCREASE reproductive success (even *if* it does mean an increase in intelligence – just ask any of us that were in Chess Club). So there will be more big skulls, but the environment isn’t selecting for big skulls, so is this really evolution?
And contrary wise, there are people reproducing today that would have never made it to puberty 200 years ago.
I keep picturing that old Outer Limits where David MacCallum “evolved” thousands of years and got a big head.
ferox, there are other selection pressures of the modern world that are new, however. Consider the reduced population growth in industrialized nations, the new pressures on sexual selection from mass media portrayals of what sexuality is, and the impact of private motor vehicle ownership on the breeding potential of 16 year olds.
As a matter of fact, I was wondering about that. Just one thing I’m curious about: What happens to the term “embryology”? I noticed Zachary uses the word “embryological” in the post, but the field is referred to as developmental biology. Is the term embryology still used? Is there any difference between embryology and developmental biology?
….the new pressures on sexual selection from mass media portrayals of what sexuality is, and the impact of private motor vehicle ownership on the breeding potential of 16 year olds
But modulate that heavily by the decoupling of sexuality from reproduction, due to effective contraception. The highest fitness (in the West) is not likely to be among those who have the most sex, it’s those who either choose to have (more than the average number of) children, or fail to practice half-way reliable birth control. Whether that correlates with anything genetic, I dunno (and quite possibly no one does).
At last something Charlie Wagner and I can agree on! He wrote:
“Just as development is the unfolding of an algorithm that is already present in the zygote at the time of fertilization, so evolution is the unfolding of an algorithm that was already present at a time before evolution began.”
The algorithm is called natural selection and, yes, it was present right before evolution began.
lt.kizhe asked: “What happens to the term “embryology”? I noticed Zachary uses the word “embryological” in the post, but the field is referred to as developmental biology. Is the term embryology still used? Is there any difference between embryology and developmental biology?”
Mostly it’s just a more fashionable name for the same thing (although one could argue that development also refers to processes and events that occur outside embryonic stages, such as larvae). For example, in the late 1980s one of the main specialist journals in the field changed its name from “Journal of Embryology and Experimental Morphology” to the much more elegant “Development”. Interestingly, Darwin used the word “development” to mean evolution.
Ricardo wrote:
“The algorithm is called natural selection and, yes, it was present right before evolution began.”
Natural selection is not an algorithmic process. An algorithm is a mathematical equation or a set of instructions in a program. It is a step by step procedure for solving a problem and it always requires intelligent input. It is necessary to define the problem and then state the specific set of instructions to solve it.
In addition, natural selection is not evolution. Evolution is the emergence of highly organized structures, processes and systems, where they did not exist before.
Only intelligence can recognize a problem, define that problem and create a series of instructions to solve it.
The homeobox contains a set of instructions for determining how the genes are expressed during development.
A more global algorithm determines which genes are turned on and in what order to effect the emergence of the highly organized structures, processes and systems that are necessary to sustain life. No such algorithm ever created itself from nothing. No combination of accidental mutations, recombinations or changes in gene frequency could have accomplished this task.
Charlie Wagner wrote:
“Natural selection is not an algorithmic process.”
John Wilkins wrote: (Apr 22 2003)
“Finally! Something Charlie and I agree on.
“Natural selection” is a sampling effect in nature that we can
*represent* as an algorithm. It is not in itself an algorithm. ”
Thanks, John!
So Charlie Wagner and I don’t agree after all… What a surprise! He said: “Natural selection is not an algorithmic process. An algorithm is a mathematical equation or a set of instructions in a program. It is a step by step procedure for solving a problem and it always requires intelligent input. It is necessary to define the problem and then state the specific set of instructions to solve it.”
Under your definition of algorithm development wouldn’t count as one either, so you can’t have it both ways. On the algorithmic nature of natural selection I agree with Dennett and Dawkins and others. But that’s not really important. Calling it an algorithm is only an analogy, a way to clarify it’s operation. But the concept of natural selection is clear and precise enough not to need these analogies, unlike much of what you write on evolution.
“A more global algorithm determines which genes are turned on and in what order to effect the emergence of the highly organized structures, processes and systems that are necessary to sustain life.”
See, I have no idea what any of that means. Now try to explain it without analogies…
A more extensive explanation can be found in Sean Carroll’s Endless Forms Most Beautiful. Carroll does a good job of writing a book for what I will call the educated layman. I’m about 2/3s of the way through it (part of my um, required reading in preparation for my master’s thesis) and as a non-physical scientist I think it finds a balance in providing in-depth details without being esoteric. These posts and books are definitely worth promoting, as so many creationist attacks on evolution seem based on an assumption that evolution is some sort of fixed science. They attack “gaps” or “flaws” in evolutionary theory as if the scientific inquiry had stopped and everyone was happy with the level of knowledge about evolution. It’s absurd of course, but the way to combat it seems to be by highlighting recent developments of the theory in various areas, and Evo Devo is a great example of how evolutionary theory within different fields comes together so nicely, and how thinking about the science in different ways provides new insight. Science will fill the gaps, not superstition.
“An algorithm is a mathematical equation or a set of instructions in a program.”
That’s wrong. An algorithm is a procedure (a finite set of well-defined instructions) for accomplishing some task which, given an initial state, will terminate in a defined end-state.
Evolution is such a procedure. It’s easiest to see if you confine yourself to RM+NS and follow a couple of generations under selective pressure. (In this case the algorithm repeats indefinitely.) There is nothing here that says the abstract instructions are manmade; here they are concretised by mutations and selective cullings.
“It is a step by step procedure for solving a problem and it always requires intelligent input.”
So this is wrong; you haven’t grasped the abstract concept of an algorithm.
You can concretize the abstract concept in several ways. One of them is to make computer software. It’s called genetic algorithms and they behave exactly as RM+NS in nature. This demonstrates both the abstraction and the concretisation nicely, unless you are a dunze.
“In addition, natural selection is not evolution.”
Not by itself, there are several mechanisms involved; but you should know this by now.
“Evolution is the emergence of highly organized structures, processes and systems, where they did not exist before.”
This is wrong too (surprise, surprise), evolution as adaption can go to simpler systems. Organisation isn’t the goal of the game, survival is, remember?
“Only intelligence can recognize a problem, define that problem and create a series of instructions to solve it.”
This is wrong since evolution is a disproof. If you contest that you have to _first_ prove that evolution was ID, of course! What were you thinking of (or with)?
The evolutionary process does not result in a predefined end-state in finite time. It’s not an algorithm.
The fact that Wagner is right about this point does not prevent his other points from being complete junk. Please stop opposing everything he says and oppose only the incorrect things — the sets are almost identical, so I don’t think a little restraint is impossible.
Experiment in Progress:
The Evolution of Bro. Bartleby’s Mind
“Thanks for the interesting post.”
“The evolutionary process does not result in a predefined end-state in finite time. It’s not an algorithm.”
I think you are missing the point on three accounts.
First, if you follow a couple of generations they will result in a predefined end-state; they will be better adapted to the current selective pressure. It’s merely that the algorithm repeats indefinitely (and the selective pressures changes et cetera). This isn’t an unusual thing; many softwares are such, for example the one that checks out the current position of your mouse. (Technically the hardware issues an interrupt when you move the mouse; but the point is that the particular hardware/software action is infinitely repeating.)
Second, that definition I gave is an abstract one. Perhaps there (must) exist some exact definition in computer science. In real life, it’s usually enough to see if you can make some graph of it, or a precise list with precise steps, that lets you, hardware or software perform the actions. If you can do it for real from the abstract definition and it performs some desired task, it’s an algorithm.
Third, there already exists softwares with genetic algorithms. You can find examples on the web, download and play around with them yourself.