There is a new book on evolution theory: The Evolution of Aging, ISBN
0978870905, by Theodore Goldsmith that discusses digital information
aspects of inheritance and their implications for evolution theory.

Darwin tells us that selective breeding and the corresponding
evolutionary mechanism of natural selection both depend on the natural
variation of characteristics between different individuals. Variation
creates differences for selection to select.

According to the book, natural variation in more complex species is not
actually "natural" in the sense of being a fundamental characteristic of
all living things. Instead, because of the digital nature of the
genetic code, the "natural" intrinsic situation is that members of a
species should nominally tend toward being genetically identical.
"Natural" variation in complex organisms is actually created and
maintained primarily by the action of a long list of complex evolved
mechanisms that process mutations including sexual reproduction, genetic
recombination, certain behaviors, etc. The degree of variation produced
by these mechanisms is described to be much greater than that produced
by the occasional propagatable mutation.

This brings up the issue of how all these variation-producing traits
evolved. It seems to be a somewhat circular situation: organisms are
evolving the means for evolving.

Further, variation considered as an evolved design feature is itself
incompatible with Darwinian evolution as generally understood. If
organisms are striving to propagate their personal designs, then
variation is adverse because it acts to reduce the ability of an
organism to do that. A Darwinian organism would rather clone itself and
therefore propagate ALL of its design characteristics than dilute its
design via sexual reproduction and other evolved variation-producing
characteristics. Cloning is the "natural", easier, route given digital
genetics.

So how did these characteristics evolve? Wouldn't an organism that had
the variation-producing characteristics be at a disadvantage relative to
one that did not (such as one that reproduced by cloning) and therefore
"select out?" An organism that happened to possess an advantageous
design would certainly seem to be less able to propagate that design.
Its descendents would likely be less able to survive, breed, etc. than
would a clone. Somehow variation-producing characteristics were able to
evolve despite fitness disadvantage, apparently because they convey an
evolutionary advantage, an improvement in the capacity for evolution.

The question: Is this a plausible idea? If not, where is the fatal
logical flaw?

If you accept these arguments, Goldsmith then goes on to suggest that
aging, seen as a design feature that deliberately limits life span, also
enhances the evolution process in several different ways. If variation
can evolve, then aging can evolve even though both are fitness-adverse.
This is counter to traditional theories of aging that say that aging is
an adverse "side effect" linked to some beneficial and therefore
evolvable trait such that there is a net Darwinian benefit.
("Beneficial" means a trait that helps in survival or reproduction as in
"survival of the fittest.")

I realize these concepts might seem, at the least, radical, but they are
nonetheless interesting.

There is a new book on evolution theory: The Evolution of Aging, ISBN
0978870905, by Theodore Goldsmith that discusses digital information
aspects of inheritance and their implications for evolution theory.

Darwin tells us that selective breeding and the corresponding
evolutionary mechanism of natural selection both depend on the natural
variation of characteristics between different individuals. Variation
creates differences for selection to select.

According to the book, natural variation in more complex species is not
actually "natural" in the sense of being a fundamental characteristic of
all living things. Instead, because of the digital nature of the
genetic code, the "natural" intrinsic situation is that members of a
species should nominally tend toward being genetically identical.
"Natural" variation in complex organisms is actually created and
maintained primarily by the action of a long list of complex evolved
mechanisms that process mutations including sexual reproduction, genetic
recombination, certain behaviors, etc. The degree of variation produced
by these mechanisms is described to be much greater than that produced
by the occasional propagatable mutation.

This brings up the issue of how all these variation-producing traits
evolved. It seems to be a somewhat circular situation: organisms are
evolving the means for evolving.

Further, variation considered as an evolved design feature is itself
incompatible with Darwinian evolution as generally understood. If
organisms are striving to propagate their personal designs, then
variation is adverse because it acts to reduce the ability of an
organism to do that. A Darwinian organism would rather clone itself and
therefore propagate ALL of its design characteristics than dilute its
design via sexual reproduction and other evolved variation-producing
characteristics. Cloning is the "natural", easier, route given digital
genetics.

So how did these characteristics evolve? Wouldn't an organism that had
the variation-producing characteristics be at a disadvantage relative to
one that did not (such as one that reproduced by cloning) and therefore
"select out?" An organism that happened to possess an advantageous
design would certainly seem to be less able to propagate that design.
Its descendents would likely be less able to survive, breed, etc. than
would a clone. Somehow variation-producing characteristics were able to
evolve despite fitness disadvantage, apparently because they convey an
evolutionary advantage, an improvement in the capacity for evolution.

The question: Is this a plausible idea? If not, where is the fatal
logical flaw?

If you accept these arguments, Goldsmith then goes on to suggest that
aging, seen as a design feature that deliberately limits life span, also
enhances the evolution process in several different ways. If variation
can evolve, then aging can evolve even though both are fitness-adverse.
This is counter to traditional theories of aging that say that aging is
an adverse "side effect" linked to some beneficial and therefore
evolvable trait such that there is a net Darwinian benefit.
("Beneficial" means a trait that helps in survival or reproduction as in
"survival of the fittest.")

I realize these concepts might seem, at the least, radical, but they are
nonetheless interesting.

There is a new book on evolution theory: The Evolution of Aging, ISBN
0978870905, by Theodore Goldsmith that discusses digital information
aspects of inheritance and their implications for evolution theory.

Darwin tells us that selective breeding and the corresponding
evolutionary mechanism of natural selection both depend on the natural
variation of characteristics between different individuals. Variation
creates differences for selection to select.

According to the book, natural variation in more complex species is not
actually "natural" in the sense of being a fundamental characteristic of
all living things. Instead, because of the digital nature of the
genetic code, the "natural" intrinsic situation is that members of a
species should nominally tend toward being genetically identical.
"Natural" variation in complex organisms is actually created and
maintained primarily by the action of a long list of complex evolved
mechanisms that process mutations including sexual reproduction, genetic
recombination, certain behaviors, etc. The degree of variation produced
by these mechanisms is described to be much greater than that produced
by the occasional propagatable mutation.

This brings up the issue of how all these variation-producing traits
evolved. It seems to be a somewhat circular situation: organisms are
evolving the means for evolving.

Further, variation considered as an evolved design feature is itself
incompatible with Darwinian evolution as generally understood. If
organisms are striving to propagate their personal designs, then
variation is adverse because it acts to reduce the ability of an
organism to do that. A Darwinian organism would rather clone itself and
therefore propagate ALL of its design characteristics than dilute its
design via sexual reproduction and other evolved variation-producing
characteristics. Cloning is the "natural", easier, route given digital
genetics.

So how did these characteristics evolve? Wouldn't an organism that had
the variation-producing characteristics be at a disadvantage relative to
one that did not (such as one that reproduced by cloning) and therefore
"select out?" An organism that happened to possess an advantageous
design would certainly seem to be less able to propagate that design.
Its descendents would likely be less able to survive, breed, etc. than
would a clone. Somehow variation-producing characteristics were able to
evolve despite fitness disadvantage, apparently because they convey an
evolutionary advantage, an improvement in the capacity for evolution.

The question: Is this a plausible idea? If not, where is the fatal
logical flaw?

Further, variation considered as an evolved design
feature is itself incompatible with Darwinian
evolution as generally understood. If organisms
are striving to propagate their personal designs,
then variation is adverse because it acts to
reduce the ability of an organism to do that. A
Darwinian organism would rather clone itself and
therefore propagate ALL of its design
characteristics than dilute its design via sexual
reproduction and other evolved variation-producing
characteristics. Cloning is the "natural",
easier, route given digital genetics.

There is a new book on evolution theory: The Evolution of Aging, ISBN
0978870905, by Theodore Goldsmith that discusses digital information
aspects of inheritance and their implications for evolution theory.

Darwin tells us that selective breeding and the corresponding
evolutionary mechanism of natural selection both depend on the natural
variation of characteristics between different individuals. Variation
creates differences for selection to select.

According to the book, natural variation in more complex species is
not actually "natural" in the sense of being a fundamental
characteristic of all living things. Instead, because of the digital
nature of the genetic code, the "natural" intrinsic situation is that
members of a species should nominally tend toward being genetically
identical. "Natural" variation in complex organisms is actually
created and maintained primarily by the action of a long list of
complex evolved mechanisms that process mutations including sexual
reproduction, genetic recombination, certain behaviors, etc. The
degree of variation produced by these mechanisms is described to be
much greater than that produced by the occasional propagatable
mutation.

This brings up the issue of how all these variation-producing traits
evolved. It seems to be a somewhat circular situation: organisms are
evolving the means for evolving.

Further, variation considered as an evolved design feature is itself
incompatible with Darwinian evolution as generally understood. If
organisms are striving to propagate their personal designs, then
variation is adverse because it acts to reduce the ability of an
organism to do that. A Darwinian organism would rather clone itself
and therefore propagate ALL of its design characteristics than dilute
its design via sexual reproduction and other evolved
variation-producing characteristics. Cloning is the "natural",
easier, route given digital genetics.

So how did these characteristics evolve? Wouldn't an organism that
had the variation-producing characteristics be at a disadvantage
relative to one that did not (such as one that reproduced by cloning)
and therefore "select out?" An organism that happened to possess an
advantageous design would certainly seem to be less able to propagate
that design. Its descendents would likely be less able to survive,
breed, etc. than would a clone. Somehow variation-producing
characteristics were able to evolve despite fitness disadvantage,
apparently because they convey an evolutionary advantage, an
improvement in the capacity for evolution.

The question: Is this a plausible idea? If not, where is the fatal
logical flaw?

If you accept these arguments, Goldsmith then goes on to suggest that
aging, seen as a design feature that deliberately limits life span,
also enhances the evolution process in several different ways. If
variation can evolve, then aging can evolve even though both are
fitness-adverse. This is counter to traditional theories of aging
that say that aging is an adverse "side effect" linked to some
beneficial and therefore evolvable trait such that there is a net
Darwinian benefit. ("Beneficial" means a trait that helps in survival
or reproduction as in "survival of the fittest.")

I realize these concepts might seem, at the least, radical, but they
are nonetheless interesting.

FROM Peoria:
Two major flawsw and one minor flaw in the argument so far. First,
the claim that "that members of a species should nominally tend toward
being genetically identical" is true only in the limit of infinite
population sizes, infinite amount of time for selection to work, and
slow mutation rates. But in the real world, mutation is producing
variation much faster than natural selection can weed it out, and the
only thing that keeps species as close to genetically identical as
they are is drift of nearly neutral alleles to fixation in finite
populations.


Second, the arguments also seem to assume that all members of the
population
live in the same environment and that the environment is unchanging.
A considerable amount of the 'natural' variation in populations can be
traced to 'natural' variations in the environment.

The minor flaw appears in the discussion of how the 'evolution of
evolvability' is forbidden by normal selectionist logic. There is
some truth to this if you only consider evolution at a single
(organism or gene) level. But if you also allow for group-level and
species-level selection, then the existence of mechanisms for
increasing the generation of variation becomes plausible.

If you accept these arguments, Goldsmith then goes on to suggest that
aging, seen as a design feature that deliberately limits life span,
also enhances the evolution process in several different ways. If
variation can evolve, then aging can evolve even though both are
fitness-adverse. This is counter to traditional theories of aging
that say that aging is an adverse "side effect" linked to some
beneficial and therefore evolvable trait such that there is a net
Darwinian benefit. ("Beneficial" means a trait that helps in survival
or reproduction as in "survival of the fittest.")

I realize these concepts might seem, at the least, radical, but they
are nonetheless interesting.


The idea that senescence and death exist in sexual organisms for the
*purpose* of allowing the variant young to compete among themselves
(without the older generation siphoning off all of the resources) is
hardly an original one. I've seen enough modeling to convince me that
this may be part of the story, but it is not the full story. The
other part is the sheer difficulty of keeping large complex organisms
from simply wearing out. Some plants (trees, mostly) are designed so
that new generations of tissue can make productive use of the older,
worn-out generations of tissue. Animals (and especially animal
central nervous systems) just can't work that way.

FROM Lawton:


But calling this "digital?" What does THAT mean? Does the author
mean "binomial" as in the way computers process information as a
series of only two conditions at each juncture, i.e., "yes" vs "no?"
or "zero" vs (1) scenarios? If the author of the book you refer to
wished to call this "digital," so be it. As Turing observed, any
mathematical relationship can be "translated" into an algorithm (i.e.
a a format expressing the same operations, but in a form which gets
there by the use of binomial recursions).

FROM Tyler:

The idea that variation-producing characteristics were able to
evolve despite fitness disadvantage because they convey an
improvement in the capacity for evolution - is widely regarded
as not the correct explanation.

In fact there are other, more direct short-term fitness advantages
to diversity-producing traits - such as sexual recombination.

That this is the case can be seen by consideration of organisms
that exhibit facultative parthenogenesis. These organisms can
clone themselves - but often choose not to do so.

Similarly, the idea that variation considered as an evolved design
feature is itself incompatible with Darwinian evolution is
equally incorrect :-(

In fact, clones are often regarded unfavourably by natural
selection - primarily since groups of genetically identical
organisms can easily be exploited by pathogens.

There are other defenses against pathogens besides adapatations that
promote diversity: immune systems, being rare, and very rapid
dispersal, with no parental care.

Immune systems allow some of the advantages of cloning without using
diversity as a defense. However the strategy is typically only
effective in the short term.

Diversity is a simple and reasonably effective defense against
pathogens - it is not surprising to find adaptations that promote it.

Perplexed wrote:

The idea that senescence and death exist in sexual organisms for the
*purpose* of allowing the variant young to compete among themselves
(without the older generation siphoning off all of the resources) is
hardly an original one. I've seen enough modeling to convince me that
this may be part of the story, but it is not the full story. The
other part is the sheer difficulty of keeping large complex organisms
from simply wearing out. Some plants (trees, mostly) are designed so
that new generations of tissue can make productive use of the older,
worn-out generations of tissue. Animals (and especially animal
central nervous systems) just can't work that way.

Although everybody recognizes that there is wear or other unrepairable
damage that could accumulate in an organism, it seems to be pretty clear
that wear cannot be the main explanation for observed life span
characteristics. This is because very similar organisms with very
similar cell biology have grossly different life spans. (e.g. mouse and
human, crow and parrot, many other examples)

There are also organisms possessing biological suicide mechanisms
that clearly are not accumulative (e.g. bamboo, octopus).

Finally, there are organisms that do not have any measurable aging
(e.g. Pacific rockfish) even at 150 years old when similar organisms
have much shorter life spans.

The currently most respected "main line" aging theories ignore group
selection, adhere to Darwinian theory, and propose that aging is an
unavoidable adverse side-effect of some beneficial function. If you
assume the beneficial function is reproduction related, this then fits
better with the observations than wear. However, the book describes
what appear to be several major logical flaws in the main line theories.

FROM Tyler:

The idea that variation-producing characteristics were able to
evolve despite fitness disadvantage because they convey an
improvement in the capacity for evolution - is widely regarded
as not the correct explanation.

In fact there are other, more direct short-term fitness advantages
to diversity-producing traits - such as sexual recombination.

That this is the case can be seen by consideration of organisms
that exhibit facultative parthenogenesis. These organisms can
clone themselves - but often choose not to do so.

Similarly, the idea that variation considered as an evolved design
feature is itself incompatible with Darwinian evolution is
equally incorrect :-(

In fact, clones are often regarded unfavourably by natural
selection - primarily since groups of genetically identical
organisms can easily be exploited by pathogens.

There are other defenses against pathogens besides adapatations that
promote diversity: immune systems, being rare, and very rapid
dispersal, with no parental care.

Immune systems allow some of the advantages of cloning without using
diversity as a defense. However the strategy is typically only
effective in the short term.

Diversity is a simple and reasonably effective defense against
pathogens - it is not surprising to find adaptations that promote it.

This is an argument for how one of the discrepancies (variation
producing features) might be resolved without violating orthodox
Darwinism and embracing some form of group selection. It seems somewhat
implausible that sexual reproduction and all the other complexity
evolved just for this one function, but possible. (Wouldn't there have
been an easier way?)

Bioteach wrote:
Perplexed wrote:

The idea that senescence and death exist in sexual organisms for
the *purpose* of allowing the variant young to compete among
themselves (without the older generation siphoning off all of the
resources) is hardly an original one. I've seen enough modeling to
convince me that this may be part of the story, but it is not the
full story. The other part is the sheer difficulty of keeping
large complex organisms from simply wearing out. Some plants
(trees, mostly) are designed so that new generations of tissue can
make productive use of the older, worn-out generations of tissue.
Animals (and especially animal central nervous systems) just can't
work that way.

Although everybody recognizes that there is wear or other
unrepairable damage that could accumulate in an organism, it seems
to be pretty clear that wear cannot be the main explanation for
observed life span characteristics. This is because very similar
organisms with very similar cell biology have grossly different life
spans. (e.g. mouse and human, crow and parrot, many other examples)

The idea is that lifespan characteristics can be explained
primarily by selection on repair and maintenance mechanisms.

Relatively short-lived creatures allocate more resources to
short-term reproduction at the expense of repair and
maintenance mechanisms. Those that live longer allocate more
resources to repair and maintenance - perhaps because growth
is resource limited, because they have a more plastic
developmental process, or because they provide more parental
care.

There are also organisms possessing biological suicide mechanisms
that clearly are not accumulative (e.g. bamboo, octopus).

Can you be more specific? There are plenty of causes of
death that are not cumulative - but they need not be
suicidal.

Also, suicide is actually /expected/ in some plants - where
the parents live near the offspring, compete for resources
with them, or act as a parasite reservoir that could
infect them.

In such cases, individual death can be adaptively favoured
by kin selection.

Finally, there are organisms that do not have any measurable aging
(e.g. Pacific rockfish) even at 150 years old when similar organisms
have much shorter life spans.

I am not sure how negligible senescence bears on the issues of
group selection or adaptive death. An organism with negligible
senescence simply has good repair and maintenance mechanisms.

Indeed, one might ask, if senescence is supposedly adaptively
favoured, why these organisms do not exhibit it.

The currently most respected "main line" aging theories ignore group
selection, adhere to Darwinian theory, and propose that aging is an
unavoidable adverse side-effect of some beneficial function. If you
assume the beneficial function is reproduction related, this then
fits better with the observations than wear. However, the book
describes what appear to be several major logical flaws in the main
line theories.

?

FROM Tyler:

The idea that variation-producing characteristics were able to
evolve despite fitness disadvantage because they convey an
improvement in the capacity for evolution - is widely regarded
as not the correct explanation.

In fact there are other, more direct short-term fitness advantages
to diversity-producing traits - such as sexual recombination.

That this is the case can be seen by consideration of organisms
that exhibit facultative parthenogenesis. These organisms can
clone themselves - but often choose not to do so.

Similarly, the idea that variation considered as an evolved design
feature is itself incompatible with Darwinian evolution is
equally incorrect :-(

In fact, clones are often regarded unfavourably by natural
selection - primarily since groups of genetically identical
organisms can easily be exploited by pathogens.

There are other defenses against pathogens besides adapatations
that promote diversity: immune systems, being rare, and very rapid
dispersal, with no parental care.

Immune systems allow some of the advantages of cloning without
using diversity as a defense. However the strategy is typically
only effective in the short term.

Diversity is a simple and reasonably effective defense against
pathogens - it is not surprising to find adaptations that promote
it.

This is an argument for how one of the discrepancies (variation
producing features) might be resolved without violating orthodox
Darwinism and embracing some form of group selection. It seems
somewhat implausible that sexual reproduction and all the other
complexity evolved just for this one function, but possible.
(Wouldn't there have been an easier way?)

It is not the hypothesis that parasites are /solely/
responsible for the origin and maintenance of sexual
recombination. There is at least one other important theory of
the origin and maintenance of sex: the gene repair theory.
Sex weeds out deleterious mutations by concentrating them in
single bodies, and which then die or fail to reproduce.
However, pressure from parasites is an important reason for
the continued existence of sexuality - and explains much of
its ecological variation.

Sex may seem like a bizarre anti-parasite adaptation, but the
answer to the question of whether there was an easier way
appears to be 'no'.

Life /may/ find other ways of coping with parasites in the
future. It may generate diversity by other means than sexual
recombination, and it may combat pathogens directly, with
medical technology, and a global immune system. If these
approaches to eliminating pathogens are successful, a
question mark may appear over the utility of sexual
reproduction in nature.

However, so far human attempts at pathogen control have been
pretty feeble. Viruses and worms cause billions of dollars of
loss in artificial ecosystems created by humans - in computer
networks. Modern computer systems couldn't be more insecure
if the NSA had designed them itself.

If human beings are really /this/ incompetent or indifferent
to pathogens, perhaps there is little hope of progress in
combating them.

Still, I attrubute the current screw-up to copyright law - which
has created a near monopoly one area. The monopolist has
proved themselves either incompetent or failing to have the
best interests of the people at heart - resulting in the current
pathogen problem.

IMO, there are signs that this type of management screw-up will
have a limited lifespan under the current political system -
too many voters want their MP3s decriminalised, and - according
to current political thought - their wishes outweigh those of
the mega corporations, who want to continue to screw them out
of their dollars.
--
__________
|im |yler http://timtyler.org/ tim@tt1lock.org Remove lock to
|reply.

Tim Tyler <seemysig@cyberspace.org> wrote in
Bioteach wrote:

There are also organisms possessing biological suicide mechanisms
that clearly are not accumulative (e.g. bamboo, octopus).

Can you be more specific? There are plenty of causes of
death that are not cumulative - but they need not be
suicidal.

Bamboo evidently reproduce by essentially cloning, like grass.
Occasionally they flower and seed. When they flower, they die. Death
is programmed to accompany blooming and clearly not a maintenance issue.
Programmed death is apparently to prevent cloning from dominating sexual
reproduction.

Octopi females stop eating after reproduction and die of self
starvation. Some Polish biologist whose name I do not remember
determined that surgically removing the eyes eliminates this behavior.
No obvious way to make this into a maintenance issue.

Salmon die of old age after mating.

I think there are bigger problems with the maintenance theories:

If an organism can build itself from essentially nothing, how come
repair is such a problem? Replacing a cell shouldn't be very much
different from growing it in the first place. Many cells, (skin, blood)
are replaced often.

Why do things like exercise and other forms of stress seem to extend
life span if maintenance is the issue? This seems the opposite of what
one would expect.

Those who do not believe in group selection think that the individual
benefits of sexual reproduction (e.g. pathogen resistance) outweigh the
seemingly major individual disadvantages allowing the major complexities
of sexual reproduction to evolve. Those who do believe in group
selection think that the major group benefits (essentially enabling the
evolution process in complex organisms) outweigh the individual
disadvantages. There is no way that either side can prove their case to
the satisfaction of the other.