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Natural Selection as an abstraction for game theory

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Numsgil:
After a great deal of reading, this is the pet idea I've formed in my mind.  I assume it's not novel, but it was an epiphany to my sleep depraved mind.

Natural selection is almost always viewed as a property of individuals, or as Dawkins imagined, individual genes.  But I think this view is limiting because it makes explaining ecological concepts constrained.  Altruism, human nationalism, etc. become difficult constructs to resolve.  They happen on abstractions order of magnitude removed from classical natural selection.

What I suggest is abstracting natural selection to being a property of any game (as in game theory) with agent(s).  Genes compete inside an organism.  Orgranisms compete within a species.  Species compete for niches.  Nations compete with other nations.  In this abstract natural selection, the goal is not to reproduce necessarily.  The goal is to maximize the probability of your existance.  And it's not so much a goal as a consequence that if you don't, you lose.

Agents which do not do this cease to exist, replaced with agents that do exist.  For individuals this means reproduction.  The more copies of you that exist, the larger the probability that you won't be wiped out by a random death.  But reproduction doesn't really make sense from the framepoint of countries as a successful strategy.  For countries, long term survival means a strong military, good diplomacy, internal stability, and growth (either in the economy or in physical borders, etc.).

The phenomenon of natural selection is the tendancy for inept players in a game to be removed.  Natural selection tends to operate on several layers at once in the real world.  Every level that has a game going on really.  Individual levels have to balance the fact that the different players on one abstraction level might be playing as a group on another abstraction layer.  You can have several games being played on several different levels.  Higher abstraction levels, though, make the results of lower level games moot if the higher abstraction game loses.

Which is where the really interesting dynamic comes into play.  Why do slime molds cooperate in such a way that a great majority of them die to ensure the survival of a few.  Why isn't every cell selfish?  Because if they were they would lose the game on the next higher abstraction layer and the game between individuals wouldn't matter.  Slime mold colonies that have too many cheaters cease to exist.

Once something "wins" a game, that game no longer exists and the level below it becomes the highest abstraction game.  Humans do not generally play as a single species against other sentient creatures because there are no other sentient species humans are competing against.  The level of abstraction falls back down to the nation states.  If we were competing against the replitoids of Gamma 6, there would still be competition between countries, but there would also be alot of cooperation.

Note that this generalized natural selection does not offer any insights into the strategies that are used in the different abstraction layers.  It does not say how to be a good species.  It only says that poor species are removed from the game.  The different abstraction layers play games of very different rule sets.  Random mutations work on a genomic level game, but would get you killed quickly in a Risk style game.

What's interesting here is that "winning" isn't selected either for or against, except in that by removing competitors (other players) you can eventually achieve a full blown win, with your existance never questioned again on this abstraction layer (until the game starts again anyway).

A beetle that pushes out all the beetles from its niche cannot ever suffer non existance unless foreign beetles invade (the game starts over) or its destroyed on another level (the planet is hit by an asteroid and explodes).

"So what?" you might be asking.  Traditional natural selection doesn't make sense in my ex nihilo sims.  There isn't reproduction, so how can there be natural selection?  Something is still happening though.  Bots that get themselves killed are still removed from the game.  This game is interesting though because it's solitare.  Bots might interact randomly, but it's not until a bot learns to reproduce and/or eat that competition really develops between the different bots (the abstraction moves to the next layer up).  In this case it's a competition against time and mutations.  Mutations will eventually cause a behavior that will kill the bot, and it'll lose.  But since point mutations are low frequency local events, a replicator will almost guarentee its indefinite existance against point mutations.

The ultimate winning strategy for this simple game is to become a self replicator.  Then it moves to the next level: competition between individuals, where classic natural selection is very familiar.

This also makes leagues have a certain logic.  The winner of a round has permanent existance rights (unless you restart a round).  The species it defeated can never again challenge the winner's existance, because it's extinct.  During this struggle, cannibalism isn't a good strategy, because while it may increase the cannibal's immediate success, it weakens its species success, and can cause the entire species (including itself) to lose to the other species.  The species that develops and allows cannibals to run free during a competition will have a higher probability of dying.

Conspec genes would probably be selected for if a league round lasted long enough for evolution to take hold.  Once this game is won, though, the abstraction collapses to the one below, between individuals, and this trait is selected against.

And the problem of big berthas we had back in the day: big berthas were the winners of the highest abstraction game: the struggle between individuals.  Once they won that, so a big bertha killed all other bots that could possibly kill it (big berthas else where don't count if they're far enough away), the abstraction falls back down to the lower level: the solitare fight against time and point mutations.

All in all it's a very useful framework for explaining alot of results that would seem to contradict the classical natural selection.  The only issue that doesn't seem clear to me are the events that need to happen to move up an abstraction layer.  Darwinbots has an abstraction ceiling.  Evolution can't seem to progress beyond competition between individuals.  And if it's artificially set up to start at a higher abstraction layer (as in the leagues), it inevitably resolves the higher abstraction and moves back down to a lower abstraction level.  I think I know why this is true for Darwinbots.  I think we solved the problem of big berthas by making waste a more real problem bots have to deal with.  I think we can raise the abstraction ceiling another notch by adding the ability to specialize.

But can this be abstracted away from our implementation?  What needs to happen in an abstraction level to cause a higher abstraction layer to form in a closed system (no immigration of other species, for example)?

Jez:
Ok, in my midly sleep depraved, ethanol distorted POV I shall try to  deal with some of the many points you have raised in a sensible  manner...
         
--- Quote from: Numsgil ---Natural selection is almost always viewed as a property of individuals, or as Dawkins imagined, individual genes.
--- End quote ---
           The  selfish gene? Altruism is explained there as a species advantage, some  'people' are willing to risk their lives for the propogation of the  species as a whole, one effect one answer is not a survival strategy.
           
           
--- Code: ---Genes compete inside an organism.
--- End code ---
           Genes make an organism? I don't see how individual genes compete unless it is organism V organism.
           
           
--- Code: ---  Species compete for niches. Nations compete with other nations. In this  abstract natural selection, the goal is not to reproduce necessarily.
--- End code ---

            A nation is a niche, a nation is a subspecies (in some ways) no reproduction = no evolution = you die.
           
           
--- Code: ---But  reproduction doesn't really make sense from the framepoint of countries  as a successful strategy. For countries, long term survival means a  strong military, good diplomacy, internal stability, and growth (either  in the economy or in physical borders, etc.).
--- End code ---
           Why not? If a  country doesn't reproduce it ceases to exist, Germany during WWII had a  medal for mothers that had lots of children.
           
           
--- Code: ---Higher  abstraction levels, though, make the results of lower level games moot  if the higher abstraction game loses .
--- End code ---
           Homo Sapieans plays the highest abstraction level? If the lower abstracition levels were removed Homo Sapiens wouldn't exist...
           
           
--- Code: ---  Why do slime molds cooperate in such a way that a great majority of  them die to ensure the survival of a few. Why isn't every cell selfish?
--- End code ---
           Selfish genes, it is not the individual it is the species that allows the genes to exist.
           
           
--- Code: ---Humans  do not generally play as a single species against other sentient  creatures because there are no other sentient species humans are  competing against.
--- End code ---
           We beat all the other competitors, we are now Cannibots fighting against outselves.
           
           
--- Code: ---The  different abstraction layers play games of very different rule sets.  Random mutations work on a genomic level game, but would get you killed  quickly in a Risk style game.
--- End code ---
           Aye, but if you played against Shakespeares infinite monkeys you would lose eventually.
           
           
--- Code: ---What's interesting here is that "winning" isn't selected either for or against
--- End code ---
           You lose, I win. Nuff said.
           
           
--- Code: ---A beetle that pushes out all the beetles from its niche cannot ever suffer non existance
--- End code ---
           Apart  from the fact it can no longer reproduce and theirfore dies. If it is  homosexual? it might but if a beatle species removes all other beatle  species from its niche then it is immmortal 'till that niche doesn't  exist or an outside influence/species/catastrophe removes it from its  niche.I agree!
           
           
--- Code: ---Traditional natural selection doesn't make sense in my ex nihilo sims.  
            There isn't reproduction, so how can there be natural selection?
--- End code ---
           Reproduction is the beginning of Natural selection, without self replication you don't have evolutionv surely?
             
   
--- Code: ---Something is still happening though.  Bots that get themselves killed are still removed from the game.
--- End code ---
   To be replaced by non mutating (I assume zerobot) non replicating  models of the original bot... Back to Shakespeares infinite monkeys...
     

--- Code: ---Bots  might interact randomly, but it's not until a bot larns to reproduce  and/or eat that competition really develops between the different  bots
--- End code ---
     Infinie monkeys. infinite monkeys, how do you think evolution evolved?
     
     
--- Quote ---Mutations will eventually cause a behavior that will kill the bot, and it'll lose.
--- End quote ---
     Or cause a mutation that wins and it will fill the assigned niche; pre something better evolving.
     
 
--- Quote ---The ultimate winning strategy for this simple game is to become a self replicator.
--- End quote ---
 
    Surely just the ultimate starting point?
   
   
--- Quote ---This also makes leagues have a certain logic.
--- End quote ---
   Bless you.  The leagues are a more controlled extension of Zerobot evotution.
   
   
--- Quote ---During this struggle, cannibalism isn't a good strategy
--- End quote ---
   Killing your species without reason rarely is.
   
 
--- Quote ---Conspec genes would probably be selected for if a league round lasted long enough for evolution to take hold.
--- End quote ---
 Leagues  should be without mutation, evolution is not. Plus the chance of a  round lasting long enough to allow positive mutations to take place in such a small enviroment are slim to none.
 
  Big Berhas are either  a problem with the evolutionary part of the program or a representation  of the Cambrian? big is better part or evolution coupled with small sim size
 
 
--- Quote ---All in all it's a very useful framework for  explaining alot of results that would seem to contradict the classical  natural selection.
--- End quote ---
 Or proving it, take your pick.
 
 
--- Quote ---Darwinbots has an abstraction ceiling.
--- End quote ---
Yes it does, you are never going to see Home sapiens evolving!


--- Quote ---Evolution can't seem to progress beyond competition between individuals.
--- End quote ---
Neither can DB evolution...


--- Quote ---I think we can raise the abstraction ceiling another notch by adding the ability to specialize.
--- End quote ---
Yes we can, DB has always moved in this direction, the specialisaton of species is only small atm but it is getting better.

Forgive me being so pedantic.  

PS if you can spot why it's not quoting probperly I would be grateful.

Edit: apparently the number of quote blocks is limited.  I replaced some as code blocks to make it format properly - Numsgil

Edit: The limit on quotes is 10 in one post - Light

Light:
With regards to altruism my understanding is that it is generally demonstrated between genetic relatives, the stronger the link the stonger the levels of altruism. So an organism is trying to ensure the survival of its genetic variation rather than the species as a whole.

Jez:
Ty Nums.

Light; members of a species are closely genetically related, they wouldn't be a species otherwise. I understand your point but that wouldn't stop me, theoretically, rescuing a child about to be killed at the cost of my life, because they weren't directly related. Altruistic moments often aren't preceeded by consideration of genetic diversity or DNA analysis. Consider the person rescuing the cat/dog from being hit by a car.

Sprotiel:

--- Quote from: Jez ---
--- Code: ---But  reproduction doesn't really make sense from the framepoint of countries  as a successful strategy. For countries, long term survival means a  strong military, good diplomacy, internal stability, and growth (either  in the economy or in physical borders, etc.).
--- End code ---
           Why not? If a  country doesn't reproduce it ceases to exist, Germany during WWII had a  medal for mothers that had lots of children.
--- End quote ---
You've clearly misunderstood Numsgil's point here. Germany didn't reproduce (well, you could say it did, since there used to be 2 Germanies, but one died...), it's the Germans that did. Similarly, I haven't reproduced yet (= I don't have children), but I'd be dead by now if all my cells had stopped reproducing at some point.

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