Exactly. Although this was not (as far as I know) part of the experiment, one could imagine a similar experiment on groups with more structure, e.g., baseball teams. It's the team that wins the most games (or the most important games) that reproduces. That team probably has pretty good players at each position, but almost certainly it has a good team structure and team organization. In other words, they work well together. That's what matters.
-- Russ Abbott ______________________________________ Professor, Computer Science California State University, Los Angeles cell: 310-621-3805 blog: http://russabbott.blogspot.com/ vita: http://sites.google.com/site/russabbott/ ______________________________________ On Sat, Jul 10, 2010 at 8:17 PM, Nicholas Thompson < [email protected]> wrote: > Perhaps if I understood the computer side of this conversation better I > wouldn't have the feeling that the chicken example is being misunderstood. > But I dont and I do (respectively). It should be remembered that no > chickens were selected during the conduct of this experiment; only > crates. What determined if crates were allowed to contribute to the next > generation was the number of eggs that the crate laid. > > Chickens changed, but selection was for crate egg production. Changed > chicken behavior mediated the change in crate reproductive output. > > Eliot Sober makes an interesting distinction between selection of and > selection for. The experiment resulted in the selction of nice chickens, > but selection was for crate egg production. > > N > > Nicholas S. Thompson > Emeritus Professor of Psychology and Ethology, > Clark University ([email protected]) > http://home.earthlink.net/~nickthompson/naturaldesigns/<http://home.earthlink.net/%7Enickthompson/naturaldesigns/> > http://www.cusf.org [City University of Santa Fe] > > > > > > ----- Original Message ----- > *From:* sarbajit roy <[email protected]> > *To: *[email protected];The Friday Morning Applied Complexity > Coffee Group <[email protected]> > *Sent:* 7/10/2010 10:51:22 PM > *Subject:* Re: [FRIAM] Real-world genetic algorithm example... help! > > How is selective breeding / clustering to optimise particular traits in > chickens any different from endogamous human clusters / societies? In India > for eg. the endgamous caste and sub-caste systems have been in place for > millenia to ensure genetic optimisation and perpetuation of a few > "desirable" traits. My mother will be comforted to learn this has been > confirmed by experiments on chickens. Previously all Bengali Brahmins had to > rely on were encyclopedias / papers like this > [1<http://en.wikipedia.org/wiki/Haplogroup_R1a1_%28Y-DNA%29>] > to confirm that "we" are bred to perpetuate an "R1a1" gene. <rol> > > Sarbajit > > On Sat, Jul 10, 2010 at 8:31 PM, Nicholas Thompson < > [email protected]> wrote: > > John, > > > > Thanks. I agree. In fact, I would argue that ANY attempt to squeeze > > spiritual juice from this particular example blunts it scientific edge. > > > > To mix a metaphor. > > > > N > > > > Nicholas S. Thompson > > Emeritus Professor of Psychology and Ethology, > > Clark University ([email protected]) > > http://home.earthlink.net/~nickthompson/naturaldesigns/<http://home.earthlink.net/%7Enickthompson/naturaldesigns/> > > http://www.cusf.org [City University of Santa Fe] > > > > > > > > > >> [Original Message] > >> From: John Kennison <[email protected]> > >> To: [email protected] <[email protected]>; The Friday > > MorningApplied Complexity Coffee Group <[email protected]> > >> Date: 7/10/2010 4:02:16 AM > >> Subject: Re: [FRIAM] Real-world genetic algorithm example... help! > >> > >> Selecting for productive coops rather than productive hens might reject > > highly productive, highly aggressive hens in favor of somewhat less > > productive, considerably less aggressive hens who would leave their > > coop-mates in peace (and therefore able to produce more eggs). Such hens > > need not have anything like a “concept” of loyalty to the coop --we > could > > redistribute these hens to different coops and without affecting coop > > productivity. But after a while, we might find we are selecting for > highly > > productive, potentially highly aggressive hens who are strongly inhibited > > against bothering a hen they grew up with. Then if we redistributed the > > hens among different coops, coop productivity would decrease. > >> > >> Are there applications to genetic algorithms? It shows you have to be > > careful about dividing the task to be done into subtasks. You don’t want > to > > overlook an algorithm for doing one subtask that provides useful > byproducts > > for another subtask. Instead of selecting for each subtask separately, > you > > might select for teams of algorithms that do the whole task. > >> > >> ________________________________________ > >> From: [email protected] [[email protected]] On Behalf > Of > > Russ Abbott [[email protected]] > >> Sent: Saturday, July 10, 2010 2:50 AM > >> To: The Friday Morning Applied Complexity Coffee Group > >> Subject: Re: [FRIAM] Real-world genetic algorithm example... help! > >> > >> It's not a good example as an illustration of GA because (1) the > > "selection" mechanism to move from one generation to the next is > > essentially select the best and shake it up. At best you might call that > > elitism plus mutation. But it is not representative of GA. (2) it has no > > explicit representation of the genome (3) there are no explicit genetic > > operators applied to one or more parents to produce children. > >> > >> The issue of whether there is mutation points out that there is no coop > > genome that is being evolved. Since there is no coop genome, it's hard to > > say that there is or is not mutation. It certainly isn't a good > > illustration of mutation for a textbook. > >> > >> You might make the case that the coop genome is the collection of the > > chicken genomes and that the offspring coop genome is generated from the > > parent coop genome by breeding the chickens. I guess you could call that > > mutation of the coop genome.So the mutation operator on the parent coop > > genome is to breed the chickens to get a new coop genome. But I think > > that's about as far as you could push it. > >> > >> If I were forced to describe this in GA terms, I would say that the coop > > genome is the sequence, in some arbitrary order, of chicken genomes. To > get > > an offspring, take a coop genome and treat the segments that correspond > to > > individual chickens as separate genomes, mate them to get offspring, and > > then concatenate the genomes of the resulting offspring to get a new coop > > genome. I've never heard of a genetic operator like that, but I guess > that > > doesn't mean you couldn't claim it as a genetic operator. > >> > >> The bottom line for me though is that the experiment is great biology, > > but it's a pretty limited and confusing example of a GA. > >> > >> > >> -- Russ Abbott > >> ______________________________________ > >> > >> Professor, Computer Science > >> California State University, Los Angeles > >> > >> cell: 310-621-3805 > >> blog: http://russabbott.blogspot.com/ > >> vita: http://sites.google.com/site/russabbott/ > >> ______________________________________ > >> > >> > >> > >> On Fri, Jul 9, 2010 at 11:12 PM, Ted Carmichael > > <[email protected]<mailto:[email protected]>> wrote: > >> Ha! I knew someone would complain about that. > >> > >> First of all, Eric is correct: the main point of the story - beyond a > > nice, illustrative example of how a GA works - is the need to properly > > define a fitness function. In the case of individual chickens, the > fitness > > function was ill-defined and didn't work very well. In particular, this > > section points out that it is not necessary to know why a good solution > is > > good. Why doesn't have to come into it ... the fitness function simply > > ensures that the best solution, no matter what the reasons are for being > > the best, can emerge from this process. > >> > >> In regards to Russ' complaints, I'm not sure I can agree that no > > crossover/mutation occurred. I haven't read the original paper yet, just > > the Huff Post treatment, so I didn't realize that the chicken clusters > > weren't mixed. That is, I just assumed that more than one cluster was > > selected among the best, and that they collectively produced the > subsequent > > generations. > >> > >> However, consider the case of mutation. Russ says there is no mutation > > within the population elements - the clusters of chickens. But > > functionally, there actually is mutation. This becomes obvious when we > > remember that a second-generation chicken coop is different from the > > first-generation coop. The genes were all there, but some of them > weren't > > expressed ... that is, they simply combined together in a different way > to > > produce a different coop. It doesn't matter that the kids have all the > > genes of the parents ... the kids are still different. > >> > >> And we know this is true because egg production went up. This couldn't > > have happened unless there was something (crossover or mutation) that > > changed from generation to generation. > >> > >> Regarding James' point, I don't know how the roosters were handled from > > generation to generation (something that is probably in the original > > paper). But I suppose they could get the next generation roosters the > same > > way they got the next generation hens - by simply hatching a few eggs. > >> > >> One final point: since GA originally got its inspiration from biology, I > > see no reason why biology can be used to illustrate GA in a textbook. > > Thoughts? > >> > >> Cheers, > >> > >> -Ted > >> > >> On Fri, Jul 9, 2010 at 10:03 PM, ERIC P. CHARLES > > <[email protected]<mailto:[email protected]>> wrote: > >> Russ, > >> Completely agreed. > >> I'm not sure how one would connect the chicken stuff in a pretty way to > > standard computer genetic algorithms. I suppose one could relate them > > together to suggest the need for variation in "selection" methods when > > using GAs. That's Ted's part. I only claimed to know how the chicken part > > worked through (either artificial or natural) selection for something > other > > than best individual production. > >> > >> Eric > >> > >> > >> On Fri, Jul 9, 2010 09:18 PM, Russ Abbott > > <[email protected]<mailto:[email protected]>> wrote: > >> It's a great story, but it's not a genetic algorithm as we normally > think > > about it. It's really just breeding. For one thing, no computer was > > involved. The point of the whole thing is to establish the notion of > group > > selection, which was forbidden in the biological world for a while. This > > experiment shows that it makes sense. > >> > >> In what sense was it just breeding? Well, what was bred was coops rather > > than chickens. So the original population was 6 coops. The best one was > > selected and propagated. The best of those was selected, etc. Not at all > > what GA is about. There was no crossover or mutation between the > > population elements -- which are coops. Of course there is crossover > among > > the chickens in the coop, but it wasn't chickens that were bred. The > > fitness function was a function applied to the coop. > >> > >> So even though it is a very nice experiment and even though it makes a > > very strong case for group selection, it's probably not a good example > for > > a chapter on genetic algorithms in a text book. > >> > >> > >> -- Russ > >> > >> > >> > >> On Fri, Jul 9, 2010 at 4:25 PM, ERIC P. CHARLES <[email protected]> wrote: > >> Shawn, > >> The two ways to answer your question would either be to invoke > artificial > > selection (i.e., because you can design a genetic algorithm to do > anything > > you want, just as chicken breeders can keep whichever eggs or to invoke > > Wilson's "trait group selection." In trait group selection you break > > selection into two parts, within-group and between-group selection. If > you > > do that, you can, under the right conditions, find that types of > > individuals who reproduce less well within any group can still > out-compete > > the competition when you look between groups. Math available upon > request. > > I have a vague memory that this has come across the FRIAM list before. > >> > >> Eric > >> > >> > >> On Fri, Jul 9, 2010 06:47 PM, Shawn Barr <[email protected]> wrote: > >> > >> Ted, > >> > >> I'm confused. Why would a genetic algorithm ever select a hen that > > produces fewer eggs over a hen that produces more eggs? > >> > >> > >> Shawn > >> > >> > >> On Fri, Jul 9, 2010 at 2:57 PM, Ted Carmichael <[email protected]> > wrote: > >> Nick, this is perfect. Thank you! > >> > >> BTW - the reason for this request is, my advisor and I were asked to > > write a chapter on Complex Adaptive Systems, for a cognitive science > > textbook. In it, I talk briefly about GA, and put this story about the > > chickens in because I thought it was a neat example. > >> > >> I'll add the references now. Much appreciated. > >> > >> -t > >> > >> On Fri, Jul 9, 2010 at 12:28 PM, Nicholas Thompson > > <[email protected]> wrote: > >> Ted, > >> > >> Ok. So, if I am correct, this was an actual EXPERIMENT done by two > > researchers at Indiana University, I think. As I "tell" the "story", it > > was the practice to use individual selection to identify the most > > productive chickens, but the egg production method involved crates of > nine > > chickens. The individual selection method inadvertently selected for the > > most aggressive chickens, so that once you threw them together in crates > of > > nine, it would be like asking nine prom queens to work together in a tug > of > > war. The chickens had to be debeaked or they would kill each other. So, > > the researchers started selection for the best producing CRATES of > > chickens. Aggression went down, mortality went down, crate production > went > > up, and debeaking became unnecessary. > >> > >> The experiment is described in Sober and Wilson's UNTO OTHERS or > Wilson's > > EVOLUTION FOR EVERYBODY, which are safely tucked away in my book case > > 2000 miles away in Santa Fe. Fortunately, it is also described in > >> > >> Dave Wilson's blog > > > http://www.huffingtonpost.com/david-sloan-wilson/truth-and-reconciliation_b_ > > 266316.html > >> > >> Here is the original reference: > >> > >> GROUP SELECTION FOR ADAPTATION TO MULTIPLE-HEN CAGES : SELECTION PROGRAM > > AND DIRECT RESPONSES > >> Auteur(s) / Author(s) > >> MUIR W. > > M.< > http://www.refdoc.fr/?traduire=en&FormRechercher=submit&FormRechercher_Tx > > t_Recherche_name_attr=auteursNom:%20%28MUIR%29> ; > >> Revue / Journal Title > >> Poultry > > science< > http://www.refdoc.fr/?traduire=en&FormRechercher=submit&FormRecherch > > er_Txt_Recherche_name_attr=listeTitreSerie:%20%28Poultry%20science%29> > > ISSN > > 0032-5791< > http://www.refdoc.fr/?traduire=en&FormRechercher=submit&FormRecher > > cher_Txt_Recherche_name_attr=identifiantsDoc:%20%280032-5791%29> CODEN > > POSCAL > >> Source / Source > >> 1996, vol. 75, no4, pp. 447-458 [12 page(s) (article)] > >> > >> If you Google "group selection in chickens," you will find lots of other > > interesting stuff. > >> > >> > >> Let me know if this helps and what you think. > >> > >> N > >> > >> Nicholas S. Thompson > >> Emeritus Professor of Psychology and Ethology, > >> Clark University ([email protected]) > >> > > http://home.earthlink.net/~nickthompson/naturaldesigns/<http://home.earthlink.net/%7Enickthompson/naturaldesigns/> > <http://home.earthlin > > k.net/%7Enickthompson/naturaldesigns/> > >> http://www.cusf.org [City University of Santa Fe] > >> > >> > >> > >> > >> ----- Original Message ----- > >> From: Ted Carmichael > >> To: The Friday Morning Applied Complexity Coffee Group > >> Sent: 7/9/2010 5:34:29 AM > >> Subject: [FRIAM] Real-world genetic algorithm example... help! > >> > >> Dear all, > >> > >> I'm trying to find reference to a story I read some time ago (a few > > years, perhaps?), and I'm hoping that either: a) I heard it from someone > on > > this list, or b) someone on this list heard it, too. > >> > >> Anyway, it was a really cool example of a real-world genetic algorithm, > > having to do with chickens. Traditionally, the best egg-producing > chickens > > were allowed to produce the offspring for future generations. However, > > these new chickens rarely lived up to their potential. It was thought > that > > maybe there were unknown things going on in the clusters of chickens, > which > > represent the actual environment that these chickens are kept in. And > that > > the high producers, when gathered together in these groups, somehow > failed > > to produce as many eggs as expected. > >> > >> So researchers decided to apply the fitness function to groups of > > chickens, rather than individuals. This would perhaps account for social > > traits that are generally unknown, but may affect how many eggs were > laid. > > In fact, the researchers didn't care what those traits are, only that - > > whatever they may be - they are preserved in future generations in a way > > that increased production. > >> > >> And the experiment worked. Groups of chickens that produced the most > > eggs were preserved, and subsequent generations were much more productive > > than with the traditional methods. > >> > >> Anyway, that's the story. If anyone can provide a link, I would be very > > grateful. (As I recall, it wasn't a technical paper, but rather a story > in > > a more accessible venue. Perhaps the NY Times article, or something > > similar?) > >> > >> Thanks! > >> > >> -Ted > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > >> > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > >> > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > >> > >> > >> Eric Charles > >> > >> Professional Student and > >> Assistant Professor of Psychology > >> Penn State University > >> Altoona, PA 16601 > >> > >> > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > >> > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > >> > >> > >> Eric Charles > >> > >> Professional Student and > >> Assistant Professor of Psychology > >> Penn State University > >> Altoona, PA 16601 > >> > >> > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > >> > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > >> > >> > >> ============================================================ > >> FRIAM Applied Complexity Group listserv > >> Meets Fridays 9a-11:30 at cafe at St. John's College > >> lectures, archives, unsubscribe, maps at http://www.friam.org > > > > > > > > > > ============================================================ > > FRIAM Applied Complexity Group listserv > > Meets Fridays 9a-11:30 at cafe at St. John's College > > lectures, archives, unsubscribe, maps at http://www.friam.org > > > > > ============================================================ > FRIAM Applied Complexity Group listserv > Meets Fridays 9a-11:30 at cafe at St. John's College > lectures, archives, unsubscribe, maps at http://www.friam.org >
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