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Emergence 149

Tangurena writes "Emergence is a field that is trying to come to grips with how new behavior emerges out of smaller units. There is no gene that determines the behavior of a hive of bees or colony of ants, but the behavior of the nest emerges from the individuals within. Some people are using cellular automata as a means of explaining higher order behavior (like Wolfram in A New Kind of Science )." Read on for Tangurena's review of Steven Johnson's 2002 book Emergence: the Connected lives of Ants, Brains, Cities and Software.
Emergence: the Connected lives of Ants, Brains, Cities and Software
author Steven Johnson
pages 288
publisher Touchstone Press
rating 8
reviewer Tangurena
ISBN 068486876X
summary A look at how new behavior can arise from assembling smaller units.

The author makes a point that there are 3 main camps of scientific study.

  1. The study of simple systems - under a few dozen variables, like electromagnetism, or celestial mechanics.
  2. The study of stochastic systems - few million to few billion variables, like actuarial sciences and genetics.
  3. The study of disorganized complexity. Systems in the middle between a dozen and a few million variables, where the second order characteristics - how they interact, is of primary concern.

Deduction and induction work for the first two camps, but for the third, the interactions cause actions and reactions which are what scientists politely call counter intuitive, meaning your first thought is Huh? Or, in other words, it behaves quite differently from what your instincts and (so-called) common sense would tell you.

There are five basic principles for developing a system (or simulation of one) which can express emergent behavior:

  1. More is different. You get a very different behavior of the system when certain thresholds are reached.
  2. Ignorance is useful. Ants communicate with a vocabulary of around 20 words/ideas.
  3. Encourage random encounters. Much of the behavior of an ant colony comes from them just bumping into each other (or external things like food, or my foot).
  4. Look for patterns in the signs. Even with the limited vocabulary of ants, they can also express things based on the decay in the pheromones they deposit.
  5. Pay attention to your neighbors. Also described as "local information can lead to global wisdom."

One of the enduring myths we have, is that of the Ant Queen. The myth supposes that there is some central planning done in an ant colony. Instead, the queen exists only to pop eggs out. Male ants have such short lives, that in most species of ants, they have no mouths to eat with; they just don't live long enough to get hungry. The production of warriors and workers is stimulated by pheromones in the colony. Information on where to gather food is gathered through random acts of bumping into things. There is no ant which tells another to go lift that bale or tote that barge. It appears that our intelligence is a by-product of the neural interactions of our brains.

The economist Jane Jacobs had been studying things like this for years, and has been demonized by the majority of economists: they want to believe in some centralized controlling force, control that force, and you control the development of your economic system. People reading her books tend to think she worships sidewalks, instead, she values the communication that can only happen on sidewalks; people meeting each other and exchanging words. You can't say "hi" to your neighbors if you are each zipping past each other on the freeway.

One can experiment with emergent behavior with some software tools. The author explains a few, of which you are most likely to have experience with SimCity.

The main difference between chaos theory and emergent behavior theory lies in a couple important differences. A chaotic system has a number of determinable feedback loops, all of which are (usually critically) dependent upon the starting conditions. Emergent behavior has more to do with feedback loops causing totally different behavior, and when some threshold (usually population) is passed, the nature of the system drastically changes.

If you are looking for sample code to simulate things, you won't find it in this book. If, however, you want to get an overview of where this field is coming from, read this book.

You can purchase Emergence: the Connected lives of Ants, Brains, Cities and Software from Slashdot welcomes readers' book reviews -- to see your own review here, carefully read the book review guidelines, then visit the submission page.

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  • by Neil Blender ( 555885 ) <> on Wednesday December 15, 2004 @05:54PM (#11097352)
    • Definition (Score:1, Funny)

      by Anonymous Coward
      Cellular automata (Noun): A cell phone-wielding social ingrate. The automata's effective IQ is proportional to the distance between phone and ear. Usually identified by loud, annoying one-sided conversations on buses and restaurants.
    • The complexity of networks has barely begin to be realized. This realization will lead to the downfall reductionism, as the very interaction itself is something new and cannot be derived directly from a "full" understanding of the agents involved. A nice example of this is the Travelling Salesman problem. Rather, not the problem itself, but the reason why it's considered NP-hard. By this I mean, as the number of nodes increases the number of elementary paths increases by "(n-1)!". Chaos, CA, Complexity
      • Presuming that only the interactions are "real" leads you directly to quantuum theory. It may not be a deep insight about the nature of reality, but it's quite useful. (And it *might* be a deep insight about the nature of reality.)

        OTOH, it has been claimed that one can remove the uncertainty and randomness from quantuum theory by invoking an appropriately chosen extra dimension (or set of them). I'm not quite clear if one needs to invoke a new dimension for each interaction that is modeled, but if this
  • Michael Crichton touches on autonomous organization processes in his book Prey...however remember that Crichton is very very afraid of technology. []
    • Re:Prey (Score:5, Interesting)

      by Rei ( 128717 ) on Wednesday December 15, 2004 @06:00PM (#11097431) Homepage
      The thing is, there's no reason to be scared of autonomous organization - it is literally everywhere around us.

      Swarming/flocking/schooling algorithms are a great example of this. All it takes is a desire to be close to your neighbors but not too close, and the swarm/flock/school functions largely on its own - it can even go around obstacles and re-merge, it optimizes into aerodynamic shapes, etc.

      I love complexity from simplicity. One of my favorites occurs from the standard predator/prey population equation. If you run it for a while, it switches into repeating cycles of population size. However, the positions and numbers of cycles are dependant on the equation conditions. If you plot the cycles vs. the starting conditions, you get this beautiful graph of the data starting at a single point, then branching, and again, faster and faster until it forms into pure chaos... and then from the chaos, emerges three clean branches, which then fall to chaos again.
      • That description you gave (branching to chaos, then three clean branches appear, and descend into chaos again), is not a description of the standard predator-prey model as you claimed, which is a system of two ordinary differential equations. Instead, the phenomenon you described comes from the discrete-time logistic equation of a single population with a carrying capacity (per-capita output per time step is a linearly decreasing function of current population size), which is a difference equation, rather
        • by Rei ( 128717 )
          Differential equations? No, it's a simple linear equation, applied recursively:

          X(n+1) = R X(n) (1 - X(n))

          R is the constant that you vary to get the bifurcation diagram.
      • If you plot the cycles vs. the starting conditions, you get this beautiful graph of the data starting at a single point, then branching, and again, faster and faster until it forms into pure chaos...

        It's called a "Feigenbaum Tree" or Bifurcation diagram []

    • While i agree with most of the Crichton opinion article, let me be the first to denounce as utter garbage. Thank you, carry on.
    • Michael Crichton was a good author 20 years ago. Now he's a luddite freak. Read Congo and Sphere to see what I mean. Don't watch the movies, they cause your neurons to go critical, and your head will radiate at 9000 degrees kelvin.
      • The thing though, even when technology *isn't* evil in Crichton's books (as in Congo) the books are still about how some discovery could change the world but doesn't (semi-intelligent apes, cloned dinosaurs, time travel, etc) -- in the end *always* the discovery gets lost and the world is no different than before. Wouldn't it be more interesting to read about how time travel or cloned dinosaurs would change society?
    • My university [] had a (surprisingly sucky) course in "The Science in Science Fiction" (eh, it was a first-year seminar). However, after reading Prey we had an actual nanotechnologist-type guy come in; he discussed the state of the field and the novel. The gist of it was that even if we could mass-produce nanomachines (which isn't happening any time soon), most these nanotechnological threats in fiction are just about impossible given the sheer energy requirements - it's not easy to deliver energy to microscop
  • There goes my Christmas book budget! Another "must-have" gets added to my list.
  • by Anonymous Coward
    Try also John H Holland 'Hidden Order' and 'Emergence: From Chaos to Order'.
  • by utexaspunk ( 527541 ) on Wednesday December 15, 2004 @05:57PM (#11097404)
    While A New Kind of Science may have lots of pretty pictures, and may be a decent survey of the field of cellular automata and its potential applications, and while Stephen Wolfram is no doubt a smart man, the quality of the book is overshadowed by his pathetically arrogant writing, wherein he pratically claims credit for CA, despite actually doing very little to even further the field. It's sad that people are beginning to think he really is a leader in the study. Please dissociate Wolfram and CA in your mind. Thanks...
    • You're just jealious because you didn't write a book, which, on every page, says "I did this, I'm so smart." Also, you don't look like George Costanza.

      But seriously, you're right that Wolfram's book read more like a reference than anything really innovative. It's not a new kind of science either: because it's not even a new kind of mathematics. His pictures are just more complex (and glossy) than everyone else's. Still, the book is useful as a primer for the neophyte.

      • by Anonymous Coward
        BS... ANKS is much less useful for the neophyte than a list of say three really insightful questions and a either some simware or an editor and gcc.

        ANKS best use is as a boat anchor.
    • by Anonymous Coward
      Wolfram's smart writing was done before, A New Kind Of Science, he has actal done a lot works behind the teory of CA's.

      But ANKs is just a book of pretty pictures, dont read the tekst at best is says nothing
    • by Anonymous Coward
      ".. a rare blend of monster raving egomania and utter batshit insanity"

      Cosma Rohilla Shalizi on S.Wolfram, A new kind of science r-automata.html []
    • No kidding. I've never before read a book in which every paragraph started with either "And" or "But." I think I'm including the opening paragraph here. If you're not laughing or shaking your head, you haven't read it.
    • I have, and I need to re-read it (once isn't enough) - but one thing I do remember, quite clearly (and annoyingly), is that it seemed that on every other page, he consistently writes how he wasn't the first person to come up with this, or that - how he was merely bringing various ideas together, ideas that existed from others (and himself) from before, into a cohesive whole. He plainly writes, many, many times, how he is merely standing on shoulders of giants.
      • I have read the book, and that is not the impression that I, nor many other people who've read it, came away with. On the contrary, he repeatedly refers to it as his discovery- "...the new kind of science I [emphasis mine] have developed...", " discovery...", " of the more important single discoveries in the whole history of theoretical science..."

        That's just in the first chapter, but it continues throughout. He makes little reference to others' work in the field, pretty much dismissing all work
  • Just from reading the review, this reminds me of Out of Control [], which may be a bit outdated but is still a very relevant look at similar concepts.
    • But the world changed while he was writing Out of Control largely due to the exaggerated importance placed on Mitchell, Hraber and Crutchfield's 1993 paper [] which cast aspersions on Langton's lambda and implicitly on the whole notion of "border of order--edge of chaos".

      Wolfram's reunification of his own old Class 3 and Class 4 under his more recent Principle of Computational Equivalence goes even further in a direction I'd rather see us retreat [] from.

      I actually read the book by Johnson reviewed here for con
  • by caramelcarrot ( 778148 ) on Wednesday December 15, 2004 @06:00PM (#11097432)
    "...using cellular automata as a means of explaining higher order behavior (like Wolfram in A New Kind of Science)."

    Well, not quite sure if it can explain as high order behavior as Wolfram yet...
  • by flumps ( 240328 )
    .. we kind of knew already that complexity can be acheived with a basic set of rules re flocking. This may be interesting, but its hardly new.

    Sounds like they are rehashing old ideas into a book just in time for Xmas to get you to splash your cash.
  • /. in the book (Score:5, Interesting)

    by JohnGrahamCumming ( 684871 ) * <> on Wednesday December 15, 2004 @06:01PM (#11097445) Homepage Journal
    This is, indeed, an interesting book and the reviewer fails to point out that Emergence goes into detail concerning the karma, moderation and meta-moderation system of this here web site.

    Author seems to think taco is a genius or something, but it's still a good read :-) Towards the end where he's talking about emergent video games I got a little bored, but definitely a book that got me thinking. Worth reading even if you are aware of the way ants behave, because you probably don't know as much about slime mold as you should.

    • you probably don't know as much about slime mold as you should.

      Ooohhh yes I do matey, I played Baldurs Gate all the way through I'll have you know.

  • ugh (Score:2, Informative)

    I read the first two chapters or so of that book. It's totally an essay strrrreeeetched into a book. Terribly boring (in a lite-on-content sort of way). On the topic of taking recommendations from Slashdot: A poster raved about "The Non-Designers Design Book," so I bought it. It's not completely worthless for total amateurs (like me), but it's pretty much written for the purpose of teaching secretaries how to make better-looking newsletters. Lesson learned.
  • by wwest4 ( 183559 ) on Wednesday December 15, 2004 @06:03PM (#11097462)
    ...but interesting, nonetheless. For two viewpoints that are more or less opposing, read Daniel Dennett and John Searle - the latter of whom is a latter-day dualist who talks a lot about emergence, aka emergent properties. Dennett thinks machines will be able to think, Searle doubts it.

    • Reminds me of an old quote about the study of AI,

      "The question of whether computers can think is like the question of whether submarines can swim." * "The question 'Can machines think?' is as ill-posed and uninteresting as the question 'Can submarines swim?'"
      - E W Dijkstra []

      Seems to me that emergent properties is what it's about. I've got to concede Dijkstra's point.

      • We cannot prove machines will think, in the same way that we cannot prove that we ourselves think. Philosophy has to solve one question before it can solve the other. (AI researchers have not come to a common agreement over what behaviors and actions can be considered intelligent, partially because this is a philosophical question.) Unfortunately, we have only figured out how to make the machine carry out the intelligent behavior in the method that we program it to do. It's still a machine carrying out a p
        • It's probably important to distinguish between the two things you've mentioned, "think" versus "act intelligently". In AI, what we usually call "thinking" is an algorithm which given a set of data (usually in a "toy world") can perceive data, act upon the world, receive feedback and alter its plan accordingly. More accurately this would be "machine learning" rather than "thinking", a word which definitely has philosophical entertwinings which may not be useful questions (as Dijkstra points out).

          Yes, ma

    • I took a Philosophy course in the early 90's, 'Mind and Machine', which focused primarily on Dennett's book, 'Consciousness Explained'. I was obtaining my BS in Computer Science, and already had a BA in Psychology, but this unrequired elective was my favorite class of all time. On page 440, after discussing Searle, Dennett says 'Complexity does matter'. Human behaviour is complex, but valid generalizations can be made when analyzing the group (hence, Sociology). But a group is composed of multiple indivi
      • > Today there is a stronger argument for Determinism: just put all the facts in
        > a big computer and you can predict any outcome (or the odds of possible
        > outcomes, with a quantum approach).

        The same laws that make the quantum computing heuristic possible are a great argument against determinism a la reductionism. Predictability has well-defined limits in terms of position and state once you arrive at a quantum scale.

        > which is more complex, the group or a single person? Or is there a threshold
  • by Tackhead ( 54550 ) on Wednesday December 15, 2004 @06:07PM (#11097495)
    > 2. Ignorance is useful. Ants communicate with a vocabulary of around 20 words/ideas.

    I knew our collective hive mind would come in handy someday:

    1. "I, for one, welcome our emergent overlords."
    2. "???"
    3. "Profit!"
    4. "In Soviet Russia, our groupthink comes from emergent behvaior, or is it the other way around?"
    5. "Who cares? Look, it's Natalie Portman!"
    6. "Does Netcraft confirm it?"
    7. "Yeah, but only in Korea."
    8. "Netcraft does not confirm it. Old people are not quite dead yet."
    9. "OK, that's the Monty Python reference out of the way. Has someone bashed China yet?"
    10. "No, and we also haven't bashed Micro$oft yet, at least not until this line.

    Crap. I'm only at #10 and the well's running dry. (What, you want me to yell "MEEPT!" or something?)

    If you're a glass-half-empty type: we won't be as useful in the underground sugar mines as I'd previously thought. We're only capable of half as many thoughts.

    If you're a glass-half-full type: or maybe we've achieved antlike emergent behavior using only ten words and ideas, making us twice as efficient as our formic emergent-behavior-exhibiting overlords!

  • by krahd ( 106540 )
    If you're interested in emergent behaviour and like sci-fi thrillers, you must read Michael Crichton's Prey [].

    I know a lot of people here seems to despise Crichton but, IMHO, he writes book that are really fun (and much better than the movies they span).. so I encourage everyone to give them a try.

    btw, if you like Prey you should read Andromeda Strain [], also...


    mod me up, Scottie!
    • There is a good reason to despise Crichton: over the years he's degenerated from a moderately talented SF/thriller writer into a Luddite ideologue whose "novels" are thinly disguised political screeds -- and in the process, he's stopped doing his homework, which for a writer in his genre (especially one with his education) is unforgivable. His later novels, including Prey, have replaced storytelling with pseudoscientific hysteria.
      • Thank you.

        His basic theme doesn't change much: advanced technology and hubris gets us into trouble that only Mother Nature, in her serendipitous magnanimity, can rescue us from. Like Andromeda Strain ... the human race was on the verge of extinction from a space-born microbe (that wouldn't have bothered us if we hadn't been overstepping our bounds in the first place by building spacecraft) and we're saved at the last minute by a random mutation. Phooey. I've never really considered Crichton to be even
    • Pray? I don't get it. Sure, I'm not a fan of Crichton's books, but they're not that bad!
  • was about coming to term with Gentoo, guess not.
  • I use the following amusing/horrifying anecdote from Dawkins [] in the Genetic Omnidominance Hypothesis [] that sheds light on the real connection between ant colonies, brains and cities:

    ...scholars of revolutions may find the following passage from chapter 4, "Arms Races and Manipulation" particularly interesting:

    "Several species of ant have no workers of their own. The queens invade nests of other species, dispose of the host queen, and use the host workers to bring up their own reproductive young

    • Several years ago, I read of an ant parasite whose life cycle includes sheep. When one of these parasites matures in the body of an ant, it causes the ant to climb to the top of a blade of grass. There, it can be eaten by a sheep to continue the parasite's life cycle.

      We had an extememly weird happening in Metro Phoenix within that last week or so. An expensive car, Porsche or something like that, hit another vehicle from behind. No one was in the Porsche. Police began checking backward from the scene of th
  • by idontgno ( 624372 ) on Wednesday December 15, 2004 @06:15PM (#11097578) Journal
    but isn't this terrain Douglas Hofstadter [] covered about twenty-five years ago in Gödel, Escher, Bach []? Does Johnson's book say much new? Has a quarter-century's "progress" in CA and AI brought us any closer to singularity []? And will I ever stop posting this comment in rhetorical question form?
    • but isn't this terrain Douglas Hofstadter covered about twenty-five years ago in Gödel, Escher, Bach?

      Exactly what I was thinking. I may have to read this book just for that comparison alone. For those who have not read it, I highly recommend's not a weekend browser, but has some fascinating insight and thought experimentation. One of the most interesting books I've ever read. And the kind of books I usually like have more pictures than words :)
    • by Anonymous Coward
      B ackwards
    • It is indeed. I read GEB many years ago. The chapters on emergence (10, 11, and 12 mostly) really fascinated me. Shortly after finishing GEB I saw this book, Emergence, and ordered it, hoping to expand my knowledge on the subject.

      Emergence was good... but to tell you the truth, I found the 3 chapters in GEB to be much more enlightening. I would recommend those 3 chapters in GEB over the book Emergence any day. Especially the "Prelude..." and "..Ant Fugue" discussions before and after chapter 10.

  • Emergence (Score:1, Interesting)

    by Anonymous Coward
    I actually quite enjoyed this book. The stuff in there about the emergence of communities and trading groups in cities as a result of simple motivations was really interesting, and got me thinking about this for a while. The way in which simple interactions within an ant colony result in complex higher level behaviours such as cemetries and food distribution are also quite amazing!

    However, it wasn't until I read Mitch Resnick's 'Turtles, Termites and Traffic Jams' that emergence and self organisation rea
  • brings up an interesting idea in his Ender's Game series of books. What if there were a sort of connection between all the ants, or birds, or creatures that show this sort of behavior, like there was with the buggers in his book. What if there is some sort of connection there that we with current tools cannot detect. Or as George Lucas put it, sort of like the Force. It's there, it allows birds/ants to communicate in a method that we can't detect. Is that possible?
    • by Anonymous Coward
      The whole point of this field is that no such connection is needed, complex behavior can arrise from simple things.
    • No, no it's not. Now go find a sci-fi thread somewhere.
    • It's there, it allows birds/ants to communicate in a method that we can't detect. Is that possible?

      Possible? Everything is. But who needs it when the things we can detect seem to run the gamut? See the original formulation of Occam's Razor.
    • What if there were a sort of connection between all the ants, or birds, or creatures that show this sort of behavior, like there was with the buggers in his book. What if there is some sort of connection there that we with current tools cannot detect. Or as George Lucas put it, sort of like the Force. It's there, it allows birds/ants to communicate in a method that we can't detect. Is that possible?

      Sure. It's also possible that they're all intelligent beings who are conspiring to act like mindless aut

  • Try 1 872346/102-1898615-3811317?v=glance [].
    It's a bit dated, since complexity theory and emergence are actually not all that new. People familiar with cellular automata modeling and games like SimCity will chuckle.

    But the book is fascinating, has great explanations of many of the concepts, and touches on many of the people who have made the study of complexity so fascinating. I'd definitely recommend it for a geek holiday gift.
  • I prefer his 2004 Book, Mind Wide Open. A very interesting read into the way the brain works. Good in conjunction with Jeff Hawkins' On Intelligence, for those interested in Cortical AI.
  • This sound like the precursor science to Isaac Asimov's fictional Psychohistory [].

    BTW has anybody else noticed the analogies between Asimov's original Foundation series and the adoption of Open Source/Free Licensed Software. We are about heading towards the second Stallman [] crises : The Merchant Princes.

    "So by the same reasoning which make me sure that the Korellians will revolt in favor of prosperty, I am sure

    we will not revolt against it. The game will be played out to it's end.

    Trader Mallow from The Merch

  • Matrix (Score:3, Interesting)

    by Kallahar ( 227430 ) <> on Wednesday December 15, 2004 @06:28PM (#11097692) Homepage
    This was also a theme from the Matrix. The machine world was not controlled by a single overlord but was instead made up of billions of different programs. All the way down to the "wind" or the "bird" programs. Taken individually they're all rather simple and pointless, but when taken as a whole they build something much more valuable.
    • Too bad they fumbled the metaphor...and it was such a great one too: the Matrix as the Veil of Maya, created by humanity acting as a hive-mind. Reality becomes obscured by the a cloud of illusions generated by society as a whole. It was all there in the first movie, but I suspect they didn't realize what they had. Instead, they made the humans into batteries (WTF? Nuclear generators would have been far more efficient) instead of actual nodes in the Matrix (apparently they forgot what the words itself meant.
  • The terms "connectionism" and "emergence" are used in the field of cognitive science to represent a particular school of thought (generally accepted as Rumelhart and McClelland's territory, which Wolfram is known to align with). This school feels that simple elements, when combined into "sufficiently large and complex" systems begin exhibiting behavior that the elements alone cannot explain.

    I think there are great chasms of logic in this.

    I highly suggest also reading a Steven Pinker book such as The Bl

    • That is "Right" with a capital "R". I'm in the final chapter of The Blank Slate which has been my train reading over quite a few weekends. It's a couple of years since I read [] Johnson and Wolfram.

      Pinker says some useful stuff, especially the notion that we are each the product of the dynamics of our youthful peer groups much more than of anything else apart from our genes. But he also sometimes goes beyond reason to defend some very temporary fashions of the new Right when a real grasp of the deeper implica
  • I quoted this excellent book and gave some future directions about using the bottom-up Emergence technique when dealing with Threat Modeling. Read the last chapter in my MSc paper Threat Modeling for Web Applications using the STRIDE model [] Comments welcome. Thanks
  • You know, as someone at an art school, I can't help but think "Gestalt Theory" when I read this summary.

  • by B747SP ( 179471 ) <> on Wednesday December 15, 2004 @06:40PM (#11097777)
    Emergence is a really interesting field to tinker in. I've been doing some work with this, have a couple of published papers on the application of agent based modelling to operations management problems.

    The essential concept is that each individual is a simple agent that operates autonomously, and makes very few very simple decisions as it goes about its work. The behaviour of one individual is unremarkable, but the behaviour that emerges from a large group of the same individuals is really quite amazing.

    Because the concepts are really quite logically simple, this stuff is really simple to program too. Just fire up perl or java or any language that has a similar capability to OO concepts, write a simple object - your agent - that behaves according to a simple set of rules and responds in defined ways to certain stimuli. Make a wrapper program to create the playing field, instantiate as many 'agents' as you see fit, and let them loose. Tweak, rinse, repeat.

    As an aside, when I was writing a simulation to emulate the behaviour of ants foraging (more to prove that perl and java were suitable languages for the task than to demonstrate anything new with ants per se), I went off and RTFM'ed quite a bit on ants. They're very interesting little critters in their own right. I picked the eyes out of the various behaviours of a bunch of different species of ants to come up with one that made a fun simulation (refer references below).

    The bare mechanical simplicity with which some of these critters operate is really quite amazing. Take, for example, the concept of trail laying. I guess it's pretty widely known that many species of ants lay trails from food sources back to the nest to guide other ants to the food. (Try: find a line of ants climbing up the wall in the kitchen or somewhere, moisten your finger, wipe straight through the line (washing off the trail). They'll be all disoriented for a little while, but they'll quickly re-establish the trail, largely by random search). Anyhoo, what's really quite cool is how one species does it. The trail is just an emission from the back end of the ant that wipes along the ground as it walks. The mechanics are such that if the ant has a full crop, it puts pressure on the digestive tract, and forces stuff out the back. If its only lightly fed, it only forces a bit out the back, if its had a big feed, it forces a lot out the back and lays a denser trail. The outcome is that the ants lay stronger trails to the better food sources. Elegant, isn't it!

    I could go on forever, but I won't. Some references below. Another behaviour that is probably even more interesting than trail laying is navigation. They're absolutely amazing. Various ants use various combinations of reference to the sun, counting the amount of ground that passes underneath them as they walk *AND* remembering turns!!!, and reference to major landmarks as they travel. Did I say amazing?

    Anyhoo, here's a bunch of references on ant behaviour if anyone's interesting.

    NOTE: slashdot doesn't like 'junk' characters, so I'm removing all the comment chars :-(
    #!/usr/local/bin/perl -w
    Dancing Ants. An agent-based simulation of ant scouting and
    foraging behaviour. Demonstrating the application of open-
    source programming tools to agent-based simulation.

    # B747SP, University of xxxxxxxxxxxx. 3rd December 2003

    # In this simulation, we define an 'ant' object with behavioural
    # patterns drawn from various published works on Biology, Zoology,
    # and Behavioural science. We define a 'foraging area', then release
    # those ants into it. And then we observe...

    # What we know about ants...

    Note: These 'definitions' merely describe the behaviour of a fictional, theoretical
    ant specifically 'bred' in the mind of the author for this specific simulation.
    Their behaviours are derived from the various species of ants studied in the
    belowreferenced research papers. The behaviour describe

    • > I picked the eyes out of [...] ants
      > ... a fun ...

      Get out more...

    • Make a wrapper program to create the playing field, instantiate as many 'agents' as you see fit, and let them loose. Tweak, rinse, repeat.

      Better yet, use a simulation environment like breve [] and you get 3d rendering, collision detection, basic physics, and a lot more for free.
      • Better yet, use a simulation environment like breve and you get 3d rendering, collision detection, basic physics, and a lot more for free.

        We did look at a bunch of those tools. An argument that I was trying to make, and trying to demonstrate, was that many common-or-garden programming languages - perl, java et al - are perfectly suitable tools for this type of work. There are a lot of simulation environments around, and they all have their quirks, their own languages, and stuff. What I wanted to demonstra

    • observations
      Theres some interesting observational research, Oscillations and Chaos in Ant Societies, R.V. Sole, O. Miramontes, and B.C. Goodwin, J. Theor. Biol. 161, pp.343-357, 1993.

      In David Suzuki's, The Sacred Balance [], Brian Goodwin (author also of, HOW THE LEOPARD CHANGED ITS SPOTS []) made some interesting observational discoveries with ants. Synchronous emergent behaviour arose when individual *chaotic* ants reached a certain density. Goodwin concluded that ...

      • ... living near the edge of chaos give
      • by goon ( 2774 )
        ... I remember reading Bart Kosko (Fuzzy thinking) and in it he describes how modelling animals nature ...

        or maybe that was Richard Dawkins in Climbing Mount Improbable []. Both are worthy reads on emergent modelling.

  • 2. Ignorance is useful.

    If that were true, my company would be the most productive on the planet.

    Is Christmas vacation here yet? :-\

  • I have long been interested in emergent systems. I picked up this book a few months ago, very excited. But one chapter in I was so frustrated I nearly stopped reading. Two chapters in I quit.

    The author seems to not be able to stay on topic. The idea is presented, then a long digression into who worked with whom and how they new each other (a needless asside into Turing's life almost did me in). Then the idea is briefly recapped.

    To be fair, I didn't finish the book, so my view may very well be unfounde

  • Interesting ideas (Score:2, Insightful)

    by xnot ( 824277 )
    Kind of like the continuum going from observing at the atomic level to observing at the macroscopic level. The physics of the atomic level is VERY different then the physics of the macroscopic level. Understandably, when you get to a point where you can't use one model over the other, things can get pretty hairy.

    Can you say that the atomic level CAUSES the macroscopic level, i.e. one level emerges out of the other? My feeling is, it doesn't make much of a difference. The interactions you get depend upon yo
  • After Thought (Score:2, Informative)

    by bgalbraith ( 741719 )
    Another good book on the subject of emergent systems is After Thought [] by James Baily. It is a quick and enjoyable read that takes a look at the evolution of mathematical and philosophical attempts at describing our universe from the ancient Greeks to modern day scientists. Specifically, he focuses on how we attempt to model the human brain electronically, and touches on parallel computing, cellular automata, genetic algorithms, and the techniques required to allow a machine to learn.
  • It's worth mentioning here that, unlike some of the other books mentioned, 'Emergence' ends up tying the concepts to modern applications. For example, it discusses's use of self-organizing groups.
  • by Zukix ( 641813 ) on Wednesday December 15, 2004 @07:34PM (#11098280)
    I found the following to be surprising and useful background for the glut of writing about complexity/emergence/universality etc. Lots of historical detail from J. S. Mill onwards about the use of emergence in philosophy. Good bibliography too of which I can recommend the Kaufman books as good fun: ent/ []
  • This seems like a fascinating book. I wrote a research paper on how local information leads to global coordination, and seems very relevant to the topics covered in the book. The idea is to take an array of nodes which are in one of two states. Each node can tell the state of only a few neighbors on either side. The idea is to find a cellular automata rule so that all states in the array converge to one state (this is known as the density classification task). This is the "local information can lead to
  • Coalescent, by Stephen Baxter.
  • wasn't this already written by Isaac Asimov?
  • Flamebait mods be ready...Truth hurts.

    This book was reviewed by Wired Magazine in 2002 when it came out. I read the book and liked it; it was insightful but redundant.

    Is it possible that there is nothing important in the world of Technetium so the front page of the hallowed Slashdot has to use two year old commercial buzz from Wired?
  • I'm surprised about the statement regarding economists supporting centralized planning of economies. Good economists understand that the free market is an emergent system, and planned centralized economies have a long history of failure.

    Of course a lot of socialist economists get the press, because there are so many liberal leftists in academia.

    Why people who believe in evolution and not in creationism yet don't believe in the emergent free market but instead believe in central socialist planning is beyo
  • It would be really interesting to try to study and correlate some apparently phenomona in animal behavior and sociology.

    For example, swarming of locusts is one such phenomenon. It does not happen every year. It does not happen everywhere. Yet, when it happens it takes the shape of enormous disasters, such as what has been happening in Africa, the Middle East and Australia. Even Cyprus and the Canary Islands are affected!

    Also, look at how some teens hanging out or at a bar would be under peer pressure an

  • The Jeff Goldblum character in "Jurassic Park" did a lot of preaching about the Park being so complex that it could not really be controlled.

    Yet, when the disaster unrolled, it was not in any way the result of complexity. Rather, the disaster was the result of deliberate sabotage by a trusted insider.

    That's a Crichton habit which bugs be severely.
    • There were also rather obvious design flaws in the Dinosaur tracking systems, so that even once they were back online they were not accurately tracking the dinosaurs.

      You could argue that the trusted insider that goes bad is part of the larger "complex system" of an amusement park, but The only real example of biological complexity I can think of was the fact that some of the animals were reproducing. But again, this was only a problem because the computer system was flawed and not properly tested..
  • It's good for a short coffee shop read.

    Much more interesting books on the subject are "Complexity" by Waldrop and "Swarm Intelligence," by I forget whom.
  • A small quibble about the top level blurb introducing this book.

    Whilst there is no single gene that determines the behaviour of an ant colony it would be inaccurate to say that there are not genes which control the behaviour. There are multiple genes which control the low-level behaviours from which the gross behaviour emerges.

    Maybe I am just being pedantic.
  • Some of the most fascinating emergent behaviour in cellular automata are self replicating automata and self repairing automata, or perhaps more strictly large scale features embedded within automata that exhibit these properties. Other fascinating areas are the ability to simulate a generic computer using a cellular automata. Whilst this may not sound very exciting it opens the possibility of building new computing architectures using small units with only local communication. If this is teamed with the ab

An egghead is one who stands firmly on both feet, in mid-air, on both sides of an issue. -- Homer Ferguson