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Self-Organization in Natural Systems. MANO Jean Pierre. Self-Organization in Natural Systems. What are the mechanisms for integrating subunits into a coherently structured entity?. Self-Organization in Natural Systems. - PowerPoint PPT Presentation
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Self-Organization in Natural Systems
MANO Jean Pierre
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• What are the mechanisms for integrating subunits into a coherently structured entity?
Self-Organization in Natural Systems
3/80
• What are the mechanisms for integrating subunits activity into a coherently structured entity?– From simple neurons to
the thinking brain– From individuals to the
society– From molecule to
pattern
Self-Organization in Natural Systems
4/80
• What are the mechanisms for integrating subunits activity into a coherently structured entity?– From simple neurons to
the thinking brain– From individuals to the
society– From molecule to
pattern
Self-Organization in Natural Systems
5/80
• What are the mechanisms for integrating subunits activity into a coherently structured entity?– From simple neurons to
the thinking brain– From individuals to the
society– From molecule to
pattern
C3H4O4
NaBrNaBrO3
HSO3
C12H8N2SO2Fe
Malonic acidSodium bromideSodium bromateSulfuric acid1,10 Phenanthroline ferrous sulfate
Self-Organization in Natural Systems
6/80
Self-Organization in Natural Systems
• Definitions• Pattern formation
In living and non-living systems• Social systems
Sociality and gregarism• Cellular systems
Cells build animals• Properties of self-organized
systems
7/80
Self-Organization in Natural Systems
• Definitions• Pattern formation
In living and non-living systems• Social systems
Sociality and gregarism• Cellular systems
Cells build animals• Properties of self-organized
systems
8/80
Definitions
• What is Chaos ? [Poincarré] [Lorenz] [Prigogine]
disorder, confusion, is opposed to order and method
“Chaos” define a particular state of a system that is characterized by the following behaviors:
• Do not repeat• Sensible to initial conditions: sharp differences can produce wide
divergent results• Moreover, ordered and characterized by an unpredictable
determinism– When moving away from equillibrium state => high organization– Non equillibrium phasis: bifurcations– Amplification => Symetry break
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Definitions
• What is Self-organization in natural systems?Self-organization is a process in which pattern at the global level of a system emerges solely from numerous interactions among the lower level components of the system. [Deneubourg 1977]Moreover, the rules specifying interactions among the system’s components are executed using only local information, without reference to the global patternIn other words, the pattern is an emergent property of the system, rather than a property imposed on the system by an external influence
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• What is an emergent property ?• Many Agents• Simple rules• Many interactions• DecentralizationEmergent properties• Unreductibility• Macro-level (odre magnitude difference)• Feed-back effect on the micro-level
Definitions
Conditions
Observations
12/80
Self-Organization in Natural Systems
• Definitions• Pattern formation
In living and non-living systems• Social systems
Sociality and gregarism• Cellular systems
Cells build animals• Properties of self-organized
systems
13/80Non-living pattern formation
• Based on physical and chemical properties– Belousov-
Zhabotinsky reaction– Bénard convection
cells– Sand dune ripples– Glass cracks – Mud cracks
14/80Non-living pattern formation
• Based on physical and chemical properties– Belousov-
Zhabotinsky reaction– Bénard convection
cells– Sand dune ripples– Glass cracks – Mud cracks
15/80Non-living pattern formation
• Based on physical and chemical properties– Belousov-
Zhabotinsky reaction– Bénard convection
cells– Sand dune ripples– Glass cracks – Mud cracks
16/80Non-living pattern formation
• Based on physical and chemical properties– Belousov-
Zhabotinsky reaction– Bénard convection
cells– Sand dune ripples– Glass cracks – Mud cracks
17/80Non-living pattern formation
• Based on physical and chemical properties– Belousov-
Zhabotinsky reaction– Bénard convection
cells– Sand dune ripples– Glass cracks – Mud cracks
18/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerization– Occular dominance
stripes
19/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerization– Occular dominance
stripes
20/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerization– Occular dominance
stripes
21/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerization– Occular dominance
stripes
22/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerization– Occular dominance
stripes
23/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerization– Occular dominance
stripes
24/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerisation– Occular dominance
stripes
25/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerisation– Occular dominance
stripes
26/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerisation– Occular dominance
stripes
27/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerisation– Occular dominance
stripes
• Most of those patterns are in fact fixed states of reactions that have occurred long time ago…
28/80Pattern formation in biological systems
• Patterns characterizing individuals– Giraffe coat– Zebra– Leopard– Vermiculated rabbitfish– Cone shells– Finger prints– Morel– Metamerisation– Occular dominance
stripes
• Most of those patterns are in fact fixed states of reactions that have occurred long time ago…
Mechanisms ?
… or process is still running.
29/80Activation-inhibition mechanism
The activator autocatalyzes its own production, and also activates the inhibitor. The inhibitor disrupts the autocatalytic process. Meanwhile, the two substances diffuse through the system at different rates, with the inhibitor migrating faster. The result: local activation and long-range inhibition
Inspired by equations of reaction-diffusion [Turing 1949]
Slow diffusion
Quick diffusion
ACTIVATEUR
INHIBITEUR
+
+ACTIVAT
OR
INHIBITOR
-
Degradation
Degradation
autocatalyzis
inhibition
30/80Activation-inhibition mechanism
• Activation-inhibition and self-organization share a common mechanism– Starting point: a homogeneous substrate
(lacking pattern)– Positive feedback
(short-range activation, autocatalyzes)– Negative feedback
(long-range inhibition)
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Self-Organization in Natural Systems
• Definitions• Pattern formation
In living and non-living systems• Social systems
Sociality and gregarism• Cellular systems
Cells build animals• Properties of self-organized
systems
Low dynamicHigh
dynamic
32/80Pattern formation in colonies activity
• Patterns resulting from the activity of a society of…
social insects– Ants– Bees– Wasps– Termites
Mammalians– African Mole-rats– Humans
33/80Pattern formation in colonies activity
• Patterns resulting from the activity of a society of…
social insects– Ant– Bees– Wasps– Termites
Mammalians– African Mole-rats– Humans
34/80Pattern formation in colonies activity
• Patterns resulting from the activity of a society of…
social insects– Ant– Bees– Wasps– Termites
Mammalians– African Mole-rats– Humans
35/80Pattern formation in colonies activity
• Patterns resulting from the activity of a society of…
social insects– Ant– Bees– Wasps– Termites
Mammalians– African Mole-rats – Humans
36/80Pattern formation in colonies activity
• Patterns resulting from the activity of a society of…
social insects– Ant– Bees– Wasps– Termites
Mammalians– African Mole-rats– Humans
37/80Pattern formation in colonies activity
• Patterns resulting from the activity of a society of…
social insects– Ant– Bees– Wasps– Termites
Mammalians– African Mole-rats– Humans
38/80Pattern formation in colonies activity
• Patterns resulting from the activity of a society of…
social insects– Ant– Bees– Wasps– Termites
Mammalians– African Mole-rats– Humans
• Several orders of size magnitude difference
• Those patterns result of the permanent activity of society’s elements…Causality and
mechanisms ?
39/80Pattern formation in colonies activity
• Environmental constraints – Openess– Heterogeneity…
• Template– Gradients– Grids…
• Stigmergy [Grassé 1959] Indirect interactions between animals– Local environmental changes (pheromones, mud
pellets…)
40/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
41/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
42/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
43/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
44/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
45/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
46/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
47/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
48/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
49/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
50/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
51/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
52/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
53/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
54/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
55/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
56/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
57/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
58/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
59/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
60/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
Those patterns result from a permanent
reorganization……mechanisms ?Alignment -
attraction• No leader• No preexisting tracks• High sensitivity to
heterogeneities• Based on the nearest
neighbor perception
61/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
Those patterns results from a permanent
reorganization……mechanisms ?
• No leader• No preexisting tracks• High sensitivity to
heterogeneities• Based on the nearest
neighbor perception
62/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
Those patterns results from a permanent
reorganization……mechanisms ?
• No leader• No preexisting tracks• High sensitivity to
heterogeneities• Based on the nearest
neighbor perception
63/80Pattern formation in biological systems
• Patterns occurring during collective movement
MicroorganismsInsects and CrustaceansSocial insectsFishesBirdsMammalians
Those patterns results from a permanent
reorganization……mechanisms ?
• No leader• No preexisting tracks• High sensitivity to
heterogeneities• Based on the nearest
neighbor perception
64/80Attraction-repulsion mechanisms
• Relations between Activation-inhibition mechanisms and attraction-repulsion mechanisms
• They share a common mechanism– Starting point: a
homogeneous substrate (lacking or different pattern)
– Positive feedback (local activation or attraction rate to aggregates size)
– Negative feedback (long-range inhibition, depletion in individuals)
Short range effect
Long range effect
+
+-ATTRACTIONSTRENGTH
CONSUMPTION of FREEPARTICLE
Slow diffusion
Quick diffusion
ACTIVATEUR
INHIBITEUR
+
+ACTIVAT
OR
INHIBITOR
-
Degradation
Degradation
65/80
Self-Organization in Natural Systems
• Definitions• Pattern formation
In living and non-living systems• Social systems
Sociality and gregarism• Cellular systems
Cells build animals• Properties of self-organized
systems
66/80
How cells build the animal ?• From one cell to the next generation…
• From one cell to the thinking brain…
• Planed mechanisms:– Expression of the genetic program
• Scale changes– And long range communication
• Self-organizing mechanisms– Reaction-diffusion (activation-inhibition)– Cells migrations (Aggregation-repulsion)
67/80
How cells build the animal ?• Why has evolution “chosen” these types of
solutions?• Biological Constraints
– Physical – Energetical – Turn over – Replication -
• Limited amount of genetic information• Enormous amount of
– Morphogenic– Physiological– Behavioral
Self-organization is one solution to this problem
complexity
68/80
How cells build the animal ?
•Cell proliferation•Cell differentiation•Cell communication•Cell memory
•Regenerative potential
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How cells build the animal ?
•Cell proliferation•Cell differentiation•Cell communication•Cell memory
•Regenerative potential
Strict genetic program
Complex triggering
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Amplification of a behaviour
(metabolism)
trigger: cell environment
How cells build the animal ?
•Cell proliferation•Cell differentiation•Cell communication•Cell memory
•Regenerative potential
71/80
How cells build the animal ?
•Cell proliferation•Cell differentiation•Cell communication•Cell memory
•Regenerative potential
ContactMechanical
Direct
Secretion diffusion
At different range and time
Indirect
72/80
How cells build the animal ?
•Cell proliferation•Cell differentiation•Cell communication•Cell memory
•Regenerative potential
Nucleus (DNA)Cytoplasm– RNA– Prote
ins– …– toxin
s
Controled exchanges
Internal state, memoryof previous events (environments)
73/80
How cells build the animal ?
•Cell proliferation•Cell differentiation•Cell communication•Cell memory
•Regenerative potential
• Accidental changes in cell environment– Backward
differentiation• Not all animals
– Global communication (blood circulationand nervous system)
• Not all cells• Wounds should
respect – Gradients– Periods of
sensibility
74/80
How cells build the animal ?
•Cell proliferation•Cell differentiation•Cell communication•Cell memory
•Regenerative potential
• Low dynamic : STRUCTURES
• High dynamic : FUNCTIONING– Neural activity– Immune system
answer
75/80
Self-Organization in Natural Systems
• Definitions• Pattern formation
In living and non-living systems• Social systems
Sociality and gregarism• Cellular systems
Cells build animals• Properties of self-organized
systems
76/80Self-Organization in Natural Systems
• The modeling is relatively easy.– Environment– Time– Topology
• Unraveling the real biological mechanisms remain extremely difficult
77/80
Self-Organization in Natural Systems
Many agents Many interactionsSimples rulesDecentralization
Emergent properties
78/80
Self-Organization in Natural Systems
• Adaptive advantages of self-organized systems– Robustness– Error tolerance– Self-repair– Ease of implementation– Simple agents.
79/80
Self-Organization in Natural Systems
Conclusion
80/80
Self-Organization in Natural Systems
• Why is all of this important?– Many biological systems have evolved
decentralized solutions to their vital challenges.
– Through self-organization, evolution has stumbled upon a wide range of extremely efficient, relatively simple solutions for solving very complex problems.
81/80
Reference and further readings
• Complexity: The Emerging Science at the Edge of Order and Chaos. aldrop 1992.
• Turtles, Termites and Traffic Jams: Explorations in Massively Parallel Microworlds. Resnick 1994.
• The Quark and the Jaguar: Adventures in the Simple and the Complex. Gell-Mann 1994.
• The Self-Made Tapestry: Pattern Formation in Nature. Ball 1999.
• Emergence: From Chaos to Order. Holland 1998.• A brief history of stigmergy. Theraulaz, Bonabeau 1999 Artif. Life 5• The formation of spatial patterns in social insects:
from simple behaviours to complex structures Theraulaz, Gautrais, Camazine, Deneubourg
• Self-organization in Nature Deneubourg Camazine 2002• Comment les cellules construisent l’animal Chandebois
2003