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Besides, does nature really think?

Introduction to Complex Systems:

How to think like nature

Russ Abbott

Sr. Engr. Spec.

Rotn to CCAE

310-336-1398

Russ.Abbott@Aero.org

1998-2007. The Aerospace Corporation. All Rights Reserved.

Unintended consequences

A bit presumptuous?

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A fable

• Once upon a time, a state in India had too many snakes.

• To solve this problem the government instituted an incentive-based program to encourage its citizens to kill snakes.

• It created the No Snake Left Alive program. – Anyone who brings a dead snake into a field office of the

Dead Snake Control Authority (DSCA) will be paid a generous Dead Snake Bounty (DSB).

• A year later the DSB budget was exhausted. DSCA had paid for a significant number of dead snakes.

• But there was no noticeable reduction in the number of snakes plaguing the good citizens of the state.

• What went wrong?

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The DSCA mechanism

Catch, kill, and submit a dead snake.

DSCA

Receive money.

Dead snakeverifier

Receive dead snake certificate. Submit

certificate to DSCA.

What would you do if this mechanism were

available in your world?

Start a snake farm.

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Moral: unintended consequences

• The preceding is an example of what is sometimes called an

unintended consequence.

• It represents an entire category of (unintended and unexpected)

phenomena in which

– a mechanism is installed in an environment, but then

– the mechanism is used/exploited in unanticipated ways.

• Once a mechanism is installed in the environment, it will be

used for whatever purposes “users” can think to make of it …

– which may not be that for which it was originally intended.

The first lesson of complex systems thinking is that one must always be aware of the relationship between systems and their environments.

The first lesson of complex systems thinking is that one must always be aware of the relationship between systems and their environments.

That’s how nature works. That’s how nature works.

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Dicrocoelium dendriticum *

• D. dendriticum spends its adult life inside the liver of its host. After mating, the eggs are excreted in the feces.

• The first intermediate host, the terrestrial snail (Cionella lubrica in the United States), eats the feces, and becomes infected by the larval parasites. … The snail tries to defend itself by walling the parasites off in cysts, which it then excretes and leaves behind in the grass.

• The second intermediate host, an ant (Formica fusca in the United States) swallows a cyst loaded with hundreds of juvenile lancet flukes. The parasites enter the gut and then drift through its body. Some move to a cluster of nerve cells where they take control of the ant's actions.

• Every evening the infested ant climbs to the top of a blade of grass until a grazing animal comes along and eats the grass—and the ant and the fluke.

• The fluke grows to adulthood and lives out its life inside the animal—where it reproduces, and the cycle continues.

* Text and image from Wikipedia.org.

See also, Shelby Martin, “The Petri Dish: The journeys of the brainwashing parasite,” The Stanford Daily, April 20, 2007. http://daily.stanford.edu/article/2007/4/20/thePetriDishTheJourneysOfTheBrainwashingParasite

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Toxoplasma gondii *

• The life cycle of T. gondii has two phases. – The sexual part of the life cycle (coccidia

like) takes place only in members of the Felidae family (domestic and wild cats).

– The asexual part of the life cycle can take place in any warm-blooded animal.

• T. gondii infections have the ability to change the behavior of rats and mice, making them drawn to rather than fearful of the scent of cats.

– This effect is advantageous to the parasite, which will be able to sexually reproduce if its host is eaten by a cat.

– The infection is almost surgical in its precision, as it does not impact a rat's other fears such as the fear of open spaces or of unfamiliar smelling food.

* Text and image from Wikipedia.org.

See also, Charles Q. Choi, “Bizarre Human Brain Parasite Precisely Alters Fear,” Live Science, April 2, 2007. http://www.livescience.com/animals/070402_cat_urine.html

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Spinochordodes tellinii *

• The nematomorph hairworm Spinochordodes tellinii is a parasitic worm whose larvae develop in Orthopteran insects.

• When it is ready to leave the host, the parasite causes the host to jump into water, where it drowns, but which returns the parasite to the medium where it grows to adulthood.

* Text and image from Wikipedia.org.

See also, James Owen, “Suicide Grasshoppers Brainwashed by Parasite Worms,” National Geographic News, September 1, 2005. http://news.nationalgeographic.com/news/2005/09/0901_050901_wormparasite.html

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• Energy (and its proxy money) is fundamental.

• Any mechanism that provides access to energy/money/resources is a potential target of unintended consequences.

• A niche:

• Energy (and its proxy money) is fundamental.

• Any mechanism that provides access to energy/money/resources is a potential target of unintended consequences.

• A niche:

Follow the energy/money

• Example: power is supplied to computer USB ports– Presumably to provide power for USB devices.– The wifi bridge uses the Internet (not USB) Port to

transfer data.– But it gets its power from the USB port.

• Energy (and its proxy money) is fundamental.

• Any mechanism that provides access to energy/money/resources is a potential target of unintended consequences.

• A niche: a way of extracting energy/money/ resources from an environment

• Energy (and its proxy money) is fundamental.

• Any mechanism that provides access to energy/money/resources is a potential target of unintended consequences.

• A niche: a way of extracting energy/money/ resources from an environment