<
marc.t...@wanadoo.fr> wrote in message
news:12953d09-e589-4ae4...@gb2g2000vbb.googlegroups.com...
> On Apr 14, 3:55 pm, "jonathan" <
wr...@gmail.com> wrote:
>
> <snip for focus>
>
>> From the paper...
>> "If we replace the search for the origin of life by the one for
>> the origin of evolution our priority first is to find a consensus
>> on the minimal conditions that would allow evolution to emerge
>> and persist anywhere in the universe."
>> "Within the paradigm of open, far from equilibrium systems that
>> should maintain their level of organization, it is possible to only
>> envisage three conditions that would permit the systems to evolve:
>> (1) Local conditions that allow the emergence of open
>> non-equilibrium structural systems, organized on a
>> macroscopic level, generated by a flow of matter and energy
>> that is continuously supplied. These open far-from-equilibrium
>> systems can maintain themselves far-from-equilibrium because
>> they are able to use the matter and energy supplied by the
>> favourable local environment;
>> (2) The systems must be able to self-replicate;
>> (3) The systems must be capable of acquiring heritable
>> structure/function properties that are relatively independent
>> from the local environment,"
>> I completely agree, as Dickinson wrote long ago, nature
>> is the result of a universal process of evolution which
>> is an internal process largely independent of outside
>> influences and driven by persistent competition of
>> opposing forces. She beat everyone to the idea of
>> self-organization.
>
> Well, thank you for having read my paper.
> However, as far as I understand the emergence of Darwinian evolution,
> it is not true that Darwinian evolution is independent of the
> environment.
Not independent, but the concept of self organization holds
that the process is highly robust to initial conditions. This
can be seen with attractor theory. The highly unconstrained
interaction of autonomous agents tends to produce two
distinct behaviors. Either converging to zero or diverging
to infinity, static or chaotic attractors. And for instance
with a static attractor, the example used is that of spinning
a ball inside a bowl, the final probable state is to come
to rest at the bottom regardless of how fast the ball was
spun or where it started. A wide range of initial conditions
can result in self organization, so it's robust, not senstive
to initial conditions. And once started, the process is mostly
internal and finds it's critical balance internally. The environment
then selects mostly between already established attractors.
This is one of the key differences between Darwin and
Complexity Science.
Just as Emily said
"Earth and sun endorse it, but it stir alone"
>On the contrary relatively specific local conditions are
> required to allow such an emergence, at least within the model I
> propose. In particular "lipidic vesicle models require specific
> conditions allowing the vesicles to emerge and persist long enough,
> including a continuous flow of matter and energy
I've been watching the Mars rover missions pretty closely, and
a lot of research has been done since the rovers landed.
A common theme of much of the new research on life elsewhere
is to find the needed energy source or persistent gradient that
can fuel such a process, just as you say. A huge list of recent
astrobiology abstracts are below, you might be surprised at
how excited and flooded with research astrobiology has
become since the rovers landed. It's gone from psuedo-science
to very mainstream in the last few years
NASA Astrobiology Conference 2012
http://abscicon2012.arc.nasa.gov/
> and the possibility
> for the waste products to be diluted in an open milieu
Right, flowing water, preferably warm.
> so that the
> system is not hindered by their increasing concentration. On today's
> Earth there are places where such conditions are fulfilled:
> hydrothermal vents, particularly the serpentinite-hosted Lost City
> Hydrothermal Field
You should see Mars if you're into hydrothermal systems,
the Opportunity rov at Meridiani shows a huge area exposed
by erosion that obviously was a horizon to horizon shallow
underground hydrothermal spring system. Notice the razor
flat horizon showing water or ice formed the landscape.
And the fact there's hardly a rock to be found from horizon
to horizon. This field was underwater, probably just underground
in a massive thermal spring as the entire field is covered with
hematite, which is iron that formed in hot water.
http://areo.info/mer/opportunity/069/tn/1P134310798ESF08AYP2583L5M1_L4L5L5L5L6.jpg.html
On as much as half of Mars, just a few meters deep and the soil is as
much as 50% water ice. And as you go deeper the temperatures and
protection from radiation steadily increases. It seems clear much
of Mars had, and even has today, a huge potential biosphere
just a few meters down.
The reason they went to Meridiani was the strong hematite
signature spanning Meridiani, and they found almost all the hematite
was found in countless billions of hematite/silicone spheres
covering the field from horizon to horizon. None in the soil.
NASA says the spheres formed in hot water, probably just
underground.
These generally come in two sizes.
Field of view roughly postage stamp size.
Small
http://marsrovers.nasa.gov/gallery/all/2/m/709/2M189317905EFFAL00P2956M2M1.JPG
http://marsrovers.jpl.nasa.gov/gallery/all/1/m/053/1M132896352EFF06ASP2956M2M1.HTML
Large
http://marsrovers.jpl.nasa.gov/gallery/all/1/m/182/1M144339407EFF3370P2907M2M1.HTML
http://marsrovers.jpl.nasa.gov/gallery/all/1/m/039/1M131649674EFF0544P2933M2M1.HTML
Wide angle view
http://areo.info/mer/opportunity/180/tn/1P144166325EFF3342P2537L5M1_L4L5L5L5L6.jpg.html
http://areo.info/mer/opportunity/012/tn/1P129250922EFF0224P2374L5M1_L4L5L5L5L6.jpg.html
http://areo.info/mer/opportunity/1861/1P293402499ESFA000P2562L5M1_L4L5L5L5L6.jpg
http://areo.info/mer/opportunity/505/tn/1P173013913EFF55VWP2559L5M1_L2L5L5L6L6.jpg.html
http://areo.info/mer/opportunity/123/1P139098299EFF2809P2267L5M1_L2L5L5L6L6.jpg
http://areo.info/mer/opportunity/183/tn/1P144428432EFF3370P2540L5M1_L2L5L5L7L7.jpg.html
http://areo.info/mer/opportunity/533/tn/1P175500101EFF57BTP2568L5M1_L4L5L5L5L6.jpg.html
And here's some recent pics from the new Mars Science Lab Rover.
It's sitting in the middle of what was a shallow pond or mudflat.
http://mars.jpl.nasa.gov/msl/multimedia/raw/?s=181&camera=MAHLI
The energy and the matter are provided by the
> vent fluids and the open milieu is the vast ocean. There are good
> arguments supporting the idea that many hydrothermal vents already
> existed on early Earth, some of which were deep-sea". The fact these
> hydrothermal vents were deep-sea is crucial as these would have
> offered protective settings from the intensive solar UV radiations and
> the frequent massive meteorite impacts suffered by early Earth.
> So, no, I cannot follow you when you assert that the emergence and the
> persistence of Darwinian evolution are (even relatively) independent
> of the environment. I think there were and presently are major
> environmental constraints.
Of course the environment matters, but what Complexity Science
has done is come up with a totally abstract version of an
evolutionary system, and that allows one to see the basic process
at work in many other contexts, from physical to social systems.
Think of the ultimate needed condition as a large interstellar
cloud of gas and dust, disturbed in some way so gravity takes over
and spontaneous cylic order emerges, stars and solar systems
and so on form. Which then provide the initial conditions for the next
hierarchy of evolved order, and so on and so on up the ladder.
Self organized systems produce the needed initial conditions.
In abstract form, the ideal initial condition is the /random disturbance
to a random system/. A condition with the widest ranges of possibility.
>See the episodes of massive extinctions in
> the past history of the Earth.
No rain no trees, but no trees no rain.
Same for extinction events, without them
life couldn't get very far up the ladder.
Stress is the other necessary initial condition
for self organization, being pushed to the edge
of chaos, or internal tipping point.
Extinction events are a sign of evolution just
as earthquakes are a sign of plate tectonics.
And both follow the same power-law form
in their distribution of events.
s
>
> <snip for focus>
>