I agree with Weyland. SG is too shiny happy.

 

Personally i've often thought that the nature of the threat in Aliens is mirrored very closely by the writing of John Wyndham. Day of the Triffids and The Kraken Wakes. Humanity see the threat but fails to take effective action and eventually becomes threatened by total extinction due to these failures. Ripley is all about brute survival, making her the ideal antidote.

Ash states that in the first movie that the Alien is more important than the crew's lives because it is a scientific discovery. The idea is that it's the first Alien lifeform humans have encountered.

I've actually thought about this a lot. After watching both Alien and Aliens (which are 57 years apart), I have to assume that while "the" Alien race is very important because of its extraordinary lethality and terrible reproduction methods, other alien species have been discovered by humans. During the mess scene in Aliens, the Marines talk about Frost getting some "Arcturian poontang" with some jokes about their (presumably) hermaphroditic anatomy. Also, the Marines are constantly talking about "bug hunts" and there's the whole "Bug Stomper" logo. In the Colonial Marines Technical Manual, they also talk about other alien lifeforms, referred to as "bee bops".

 

I don't know if humans had encountered sapient alien life, but they certainly have encountered sentient alien life.

I wouldn't say anything about certainty in regards to it. It's pretty much ambiguous. No movie has really gone on to elaborate on other alien species within the setting. No movie or game even. I doubt the comics have, either. Arcturians could just be a human off-shoot or genetically engineered. The dialogue in Aliens heavily implies (to the point where it is more than a reasonable certainty) that they have encountered other alien species, but nothing that's positively sentient/intelligent. And if it wasn't for the single exchange in regards to Arcturians, we'd have no reason to think otherwise.

Stargate style its totally diferent from alien films. Alien films are more in a dirty realistic way.

 

Obviously I did not mean they had the same atmosphere or style.

 

Regarding humanoid aliens: You obviously haven't watched the show. Almost any race that looks like humans is actually a human or evolved from a common ancestor to humans.

 

Furthermore, even if the above weren't so, I'd disagree with you. The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe. It's obviously a (note the implicit plural) local maxima for the fitness landscape of evolution on Earth (and Earth-similar planets).

Furthermore, even if the above weren't so, I'd disagree with you. The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe. It's obviously a (note the implicit plural) local maxima for the fitness landscape of evolution on Earth (and Earth-similar planets).

Depends on what you call "successful"... some would argue that facet eyes, exo-skeleton and six limbs are a more successful construction. Want to place bets who is the more adaptable family of species on this planet?

The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe.

The reason it's the "most mathematical successful model on Earth for so many species" is that those species have common ancestors. It's not a derivative of being most fit for the landscape, it's features of the genetic line that have been good enough to not simply cause all the related species to fail at the important tasks for survival.

Stargate style its totally diferent from alien films. Alien films are more in a dirty realistic way.

 

 

Furthermore, even if the above weren't so, I'd disagree with you. The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe. It's obviously a (note the implicit plural) local maxima for the fitness landscape of evolution on Earth (and Earth-similar planets).

 

Sorry, but thats wrong. Evolution its totally based on genetic mutation, and mutation its totally random. So probabilities of another similar evolution from a singel cell (earth like) finishing in the 2 eyes, 2 tails 2 feet model as a result are 0,000000000000000000000000000000000000000000000000000000000000000000001% (and i give you that 0,.....1% coz imposible its nothing).

 

"Mathematical successful" has nothing to do whit biology and genetics. Random mutation in a genetic secuence its the ABC of evolution.

 

 

ADN Its just a way, could be more. Just change carbon for silicon.

Stargate style its totally diferent from alien films. Alien films are more in a dirty realistic way.

Incidentally, the Stargate, Battlestar, or Firefly licenses would all make awesome settings for an RPG.

Stargate style its totally diferent from alien films. Alien films are more in a dirty realistic way.

 

Furthermore, even if the above weren't so, I'd disagree with you. The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe. It's obviously a (note the implicit plural) local maxima for the fitness landscape of evolution on Earth (and Earth-similar planets).

 

Sorry, but thats wrong. Evolution its totally based on genetic mutation, and mutation its totally random. So probabilities of another similar evolution from a singel cell (earth like) finishing in the 2 eyes, 2 tails 2 feet model as a result are 0,000000000000000000000000000000000000000000000000000000000000000000001% (and i give you that 0,.....1% coz imposible its nothing).

 

"Mathematical successful" has nothing to do whit biology and genetics. Random mutation in a genetic secuence its the ABC of evolution.

 

ADN Its just a way, could be more. Just change carbon for silicon.

 

Are you completely ignorant? Evolution is an optimisation problem with a constantly changing fitness landscape.

 

Evolution is not solely based upon random mutation. Random mutation is simply one of the methods used to jump out of local maxima in the fitness landscape. A local maxima is a stable species, one which is generally optimal for all given conditions. Random mutation pushes us out of this local maximum from time to time in order to search for a higher maximum, because one problaby exists, ESPECIALLY if there's a changing fitness landscape. If random mutation is too low, species will become stuck in local maxima and with an evolving fitness landscape eventually die out. If mutation is too high, desirable traits can be lost unnecessarily. Random mutation is only one method of jumping out of a local maxima/minima, and evolution actually employs many other little tricks.

 

A pictorial example from wikipedia: http://en.wikipedia.org/wiki/Image:Fitness...ape-cartoon.png

 

Finally, it is invigorating to know that all I've just said isn't simply a theory. Concrete proof of the general idea represented by representing evolution as an optimisation problem exists under the name of "convergent evolution". This is when two different, completely unrelated species occupy the same maxima in a fitness landscape, due to similar or identical selective pressures. Essentially, they evolve to both have a trait independently. Examples here http://en.wikipedia.org/wiki/Convergent_ev...Animal_examples

 

Also related is parallel evolution (independent species evolve analogous structures in the same environment at the same time) and evolutionary relay (parallel evolution but the two species do not live at the same time, e.g. sharks and icthyosaurs).

 

Divergent evolution: two related species evolving away from each other is due to one species being pushed out of one local optima into another which is also stable in the fitness landscape, and often is not related to the local optima of the species it evolved from (that is: they occupy different ecological niches, e.g. one bird might evolve from eating plants to eating insects)

 

After all, surely you had to wonder how something like a whale (a mammal with relatives like deer or mouse) could go from land to sea and yet have the same basic structures as a shark, which was a COMPLETELY unrelated species that never left the sea?

 

If you'd like to argue with me on this one, feel free to do so in another thread, but I've got quite a few courses in optimisation and evolutionary biology under my belt, plus the support of immense amounts of scientific literature and research papers. Hell there's an entire field of computer science devoted to solving optimisation problems by emulating evolution, since it's a good method for some types of problem.

 

I'm sure you'd love some reference material, so why not start with wikipedia then branch into some scientifc papers:

http://en.wikipedia.org/wiki/Fitness_landscape

http://en.wikipedia.org/wiki/Fitness_%28biology%29

http://en.wikipedia.org/wiki/Optimization_...ics)#Techniques (specifically hill climbing, genetic algorithms, simulated annealing, and the like)

http://en.wikipedia.org/wiki/Genetic_algorithms (how using nature's approach to solving the evolutionary optimisation problem has allowed us to solve our own optimisation problems)

http://en.wikipedia.org/wiki/Parallel_evol...tion_in_mammals (parallel evolution in mammals)

 

An example in practice: http://bioinformatics.oxfordjournals.org/c...t/24/1/34?rss=1

 

A good introduction for beginners to complexity is the book "Frontiers of Complexity" by Peter Coveney & Roger Highfield

 

Furthermore, even if the above weren't so, I'd disagree with you. The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe. It's obviously a (note the implicit plural) local maxima for the fitness landscape of evolution on Earth (and Earth-similar planets).

Depends on what you call "successful"... some would argue that facet eyes, exo-skeleton and six limbs are a more successful construction. Want to place bets who is the more adaptable family of species on this planet?

 

You are preaching to the converted. That's exactly what the last sentence of that post you quoted means: humanoid/mammalian structures are not the only good solutions.

 

The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe.

The reason it's the "most mathematical successful model on Earth for so many species" is that those species have common ancestors. It's not a derivative of being most fit for the landscape, it's features of the genetic line that have been good enough to not simply cause all the related species to fail at the important tasks for survival.

 

You just contradicted yourself.

 

2 eyes, two hands, two feet, a tail, is a structure which existed before mammals, birds, reptiles, amphibians and dinosaurs, all split long ago. And the fact that the majority of each group still retains these features after all this time indicates it is a HIGHLY successful local optima. Humans still have a tail bone, whale skeletons show what look like hands and feet. Other solutions do exist, and most are competing with ours. Examples would be arachnid and insectoid structures, but we should probably also consider plants (although they've evolved to occupy mutually exclusive niches to us for the most part).

 

The snake is an example of random mutation pushing a species out of one local optima into another. It survived not because the lack of hands/feet was necessary but because in this state it did not lose any evolutionary advantage - this still amounts to being fit for the landscape.

Oh and Weyland, "0,000000000000000000000000000000000000000000000000000000000000000000001%" is actually quite a large number when you're talking about evolution. I can imagine a lot of mutations have a lower chance of occuring. I mean you're talking billions of years, trillions upon trillions of organisms at any one point in time between those billions of years, and finally a mutation structure could last for hundreds of millions of year (as many have done). Really, in light of all that, life on Earth was not just possible, but inevitable - the only question was "when?".

 

Enough of me and genetics. I agree with Jaguar that they'd make excellent RPG settings, SG & BSG especially.

Edited December 27, 200718 yr by Krezack

You just contradicted yourself.

No, I didn't. There's a massive difference between a supposed optimal and being fit enough to not die. There's enough variation within each species alone to demonstrate that fact. If there was only an optimal, then you'd only ever see one species within any given region. The fact that multiple species can reside within the same area demonstrates that evolution does not revolve around optimals.

 

The only thing demonstrated is that species with these features were capable of surviving. They made a passing grade. They didn't make an optimal grade.

Edited December 27, 200718 yr by Tale

You just contradicted yourself.

No, I didn't. There's a massive difference between a supposed optimal and being fit enough to not die. There's enough variation within each species alone to demonstrate that fact.

 

You said: "It's not a derivative of being most fit for the landscape, it's features of the genetic line that have been good enough to not simply cause all the related species to fail at the important tasks for survival.", implying you do not believe optimisation or a fitness landscape has anything to do with mathematically modelling evolution.

 

Now you change to saying that being fit enough not to die is not the same as being in a local maximum in a fitness landscape. Ignoring the fact that fitness and survival are not the same (and indeed, fitness is the aim of evolution, NOT survival, though a desire to survive can be handy to ensure reproduction in some species), I'll try to reply to the stance you took in your latest post.

 

What does fitness mean? Capability to reproduce. What's a local maxima in a fitness landscape? A point in the fitness landscape which signifies an organism is fit - that it is surviving and reproducing. What if one point is higher than another? It means that at the moment (changing fitness landscape over time, remember), the higher maxima means higher rate of reproduction. So obviously some local maxima imply higher fitness more than others, but all maxima imply fitness. To me that's the same as saying "any local maxima means an organism is fit enough not to die before reproducing", regardless of how well it is doing in comparison to other species, no?

 

EDIT: You've edited your post. Go back and read my posts. I have specifically stated local optima, while you imply I've been saying global optima.

Edited December 27, 200718 yr by Krezack

What I'm saying is that you can't imply an optimal. Even a local one. But perhaps I'm misunderstanding how the word is being used.

 

Reading over what you've supplied, it seems optimal is being used as a term to reference "best achieved." Whereas I interpreted what you were saying as "best possible."

 

I, however, still have a contention with your claims. The notion that a common features on Earth can be extrapolated to other Earth-like planets seems to make unnecessary assumptions. The idea of a genetic toolkit http://en.wikipedia.org/wiki/Evolutionary_...genetic_toolkit can easily imply otherwise. If all animals share the same toolkit, it's a logical explanation for similarities.

it became clear that the diversity of animal morphology was not the result of different sets of proteins regulating the development of different animals, but from changes in the deployment of a small set of proteins that were common to all animals.[98] These proteins became known as the "developmental toolkit"

http://en.wikipedia.org/wiki/History_of_ev...hought#Evo-devo

 

If you change the toolkit, quite likely everything changes. The optimization problem remains, however the means to optimize would change.

 

 

Run an example problem for trying to find an optimal route of a delivery van through traffic. Now give the cars the ability to fly, or limit turns to only 15 degrees.

Edited December 27, 200718 yr by Tale

I had just been about to echo Tale. Optimal to me is the mathematical optimal, meaning best possible.

 

Evolution is lazy. It doesn't make you better, it simply kills off those least lowest on the ladder of optimisation.The net result being an appearance of optimisation. However, if extinction pressures are reduced by food surpluses, good weather, etc then evolution takes time to chill out too.

 

At least that's what I was taught.

 

Anyway, the point is that there could be all kinds of neat weirdness out in the cosmos. There's some pretty weird stuff here on Earth (or used to be) in the jungles, underground caves, volcanic vents, and atolls.

An optimum is a maximum or minimum. They are also called extrema or critical points. http://en.wikipedia.org/wiki/Local_optimum

 

I can understand how one might confuse "optimum" it with the word "optimal".

 

Regarding a "genetic toolkit", that's the strongest argument against convergent evolution of species on different planets, yes. To generalise it further, can we even assume the the other species use RNA/DNA as their self-assembling information carrier molecule? Even so, the thing to remember is that the genetic makeup doesn't need to be the same. All that needs to be the same is the selective pressures (which on an Earth-similar planet is a logical assumption to make). Then there's an OK chance of seeing eye-like structures, and limbs. Which is what I've been arguing: that eyes and limbs could easily evolve on Earth-like planets (so TV shows aren't necessarily invalidating science), not that they will or must evolve.

 

I had just been about to echo Tale. Optimal to me is the mathematical optimal, meaning best possible.

 

Evolution is lazy. It doesn't make you better, it simply kills off those least lowest on the ladder of optimisation.The net result being an appearance of optimisation. However, if extinction pressures are reduced by food surpluses, good weather, etc then evolution takes time to chill out too.

 

Appearance of optimisation? That is optimisation. Optimisation as applied to scientific, industrial and business problems does exactly what evolution does: it finds a "good enough" solution or local optimum. Finding the global optimum, if it even exists, is typically an NP problem, and hence out of the question.

 

Optimisation is a ubiquitus field and can be applied anywhere you want to improve something or are searching for the best solution. Because the universe is composed of equilibriums and laws like "nature abhors a vacuum", the universe is always trying to find a balance or "optimal solution". Annealing and evolution are two similar approaches to solving these problems - and they certainly weren't invented by man, though we now use them to solve other optimisation problems.

 

Regarding evolution is lazy: To a point. When pressures are lowered, you typically get exponential growth because fitness has increased so much. With exponential growth you've got competion for resources so you're back to square one: selection pressures. It is in this way that even if only one organism survived some great catastrophe on earth, if it had a high fitness in its new environment, it would eventually evolve into many different organisms. (Because of random mutations and other forces used to jump out of local optima in search of better optima, even if the local optimum was a good one)

 

Disclaimer: I'd just like to mention that my posts are lengthy not because I'm trying to make a point, but because I love talking about optimisation and biology.

Edited December 28, 200718 yr by Krezack

Stargate style its totally diferent from alien films. Alien films are more in a dirty realistic way.

 

Furthermore, even if the above weren't so, I'd disagree with you. The fact that the 2 eyes, 2 hands, 2 feet and a tail model has been the most mathematical successful model on Earth for so many species, both in land and see, indicates to me that it's got real potential and is likely to be something found elsewhere in the universe. It's obviously a (note the implicit plural) local maxima for the fitness landscape of evolution on Earth (and Earth-similar planets).

 

Sorry, but thats wrong. Evolution its totally based on genetic mutation, and mutation its totally random. So probabilities of another similar evolution from a singel cell (earth like) finishing in the 2 eyes, 2 tails 2 feet model as a result are 0,000000000000000000000000000000000000000000000000000000000000000000001% (and i give you that 0,.....1% coz imposible its nothing).

 

"Mathematical successful" has nothing to do whit biology and genetics. Random mutation in a genetic secuence its the ABC of evolution.

 

ADN Its just a way, could be more. Just change carbon for silicon.

 

Are you completely ignorant? Evolution is an optimisation problem with a constantly changing fitness landscape.

 

 

No, im a genetic engineer, so ignorant its not a proper adjective.

 

I have been working whit the PCR for ages in the University of Oviedo (Asturias, Spain), whit the restriction enzyme mapping in particular.

 

Every mutation in the genetic secuence, its just an error of transcription, these mutations are letal or totally useless in the 90%, "the shearch for a higher maximun" seems to be a conscious mechanism...and it doesnt work in that way. Thats kind of random mutation represent the main steps in the evolution chaine. The eviroment and the reproduction success make the rest of the work. But that has nothing to do whit mathematical, and more whit just random changes in the eviroment or the genetic secuence. Its a totally blind process.

 

Two examples:

 

a) A population of mamals (call it X). All of the have the same size of neck. But the eviroment changes, the trees are taller now, so the mamals in the population X whit the longest neck will have reproduction success, short necks will die. As long as the "long neck" survive, they will produce long necks...so the short neck mamals of the population will disappeared. Thats eviroment and reproduction success

 

b) A population of Butterflies, they live in a wood, they are white, and the birds dont touch them coz the trees are white, so the butterflies are "invisible" among them. There is a mutation in the population of butterflies, very few of them are black 1/1000. But near the wood some corporation construct a factory (a lot of polution) The trees are now bronw coz the polutioned air "paint them". Black butterflies have now better reproduction succes, and the birds hunt the wite ones...Mutation and reproduction success

 

Mutation, eviroment and reproduction success.

Edited December 28, 200718 yr by Weyland

Your knowledge of biology is near flawless I presume, and I apologise for calling you ignorant. But optimisation is not a conscious mechanism. That's the same claim intelligent design proponents claim as a flaw for evolution, and if you can see why their claim is false it's the same reasoning for why optimisation in nature isn't a conscious mechanism. Also, those two examples you just gave are both examples of leaving one local optimum for another. The first uses crossover to jump out of a local optimum in search of a (possibly) better optimum, the second uses mutation to do the same. Although that black butterfly survival example is a fascinating example of microevolution which occurred during the industrial revolution, no?

 

Viewing evolution as an optimisation approach doesn't change anything you've learnt. It simply offers a different perspective into evolution and a newfound understanding of some of the previously mysterious mechanisms and occurrences in nature.

I think you two should just make out (not up).

Only if they're chicks, tale. Only if they're chicks.

Or really pretty men!

 

 

 

 

Wait...uh, nervemind.

Edited December 28, 200718 yr by Musopticon?

Hang on. Can we slow up for us dim kids? I only spent one year studying evolution, so I seem to be at a disadvantage. I'm also still sick and coughing up blood...

 

Optimum and optimal are essentially the same thing. Evolution doesn't optimise. i found the word I was looking for. it 'satisfices'. http://en.wikipedia.org/wiki/Satisficing . Wikipedia agrees with my preconception that this is strongly distinct from optimisation.

 

If this is wrong, then please explain clearly and with cartoons if possible.

Your knowledge of biology is near flawless I presume, and I apologise for calling you ignorant. But optimisation is not a conscious mechanism. That's the same claim intelligent design proponents claim as a flaw for evolution, and if you can see why their claim is false it's the same reasoning for why optimisation in nature isn't a conscious mechanism. Also, those two examples you just gave are both examples of leaving one local optimum for another. The first uses crossover to jump out of a local optimum in search of a (possibly) better optimum, the second uses mutation to do the same. Although that black butterfly survival example is a fascinating example of microevolution which occurred during the industrial revolution, no?

 

Viewing evolution as an optimisation approach doesn't change anything you've learnt. It simply offers a different perspective into evolution and a newfound understanding of some of the previously mysterious mechanisms and occurrences in nature.

 

Well, we are talking about the same whit different words . Im wondering if the entropy has a role in the evolution chaine...

And yep, it was an example of the industrial revolution era.

Hang on. Can we slow up for us dim kids? I only spent one year studying evolution, so I seem to be at a disadvantage. I'm also still sick and coughing up blood...

 

Optimum and optimal are essentially the same thing. Evolution doesn't optimise. i found the word I was looking for. it 'satisfices'. http://en.wikipedia.org/wiki/Satisficing . Wikipedia agrees with my preconception that this is strongly distinct from optimisation.

 

If this is wrong, then please explain clearly and with cartoons if possible.

 

I'm actually kind of sick myself. Was suffering from dehydration sickness early (dad got us lost hiking in the Blue Mountains... blundering around for 40km or so without water or food for a few hours before we found signs of civilisation). As a reference point it is 12:30 midnight in Australia at the moment and my thermometer reads 27 Celsius.

 

Many terms in mathematics appear the same, but that doesn't mean you should interchange them. I suppose you could say "locally optimal" and "globally optimal" if you like. What's important is that you distinguish "local" and "global" or you get the confusion Tale had earlier. Without this distinction the entire purpose of using optimisation to solve NP problems is moot (because NP problems seek a local optimum rather than a global optimum).

 

Regarding satisficing: Actually, if you'll check the section on neural nets (comp sci, the only area slightly related to evolution), it states satisficing is a specific case of optimisation. But really, evolution isn't satisficing because it doesn't have inbuilt constraints or a "this enough factor" to dictate when to stop searching for new local optima. Evolution doesn't stop at a local optimum. If there's something better it often finds it (random mutation), but it also often moves from a good local optimum to a worse local optimum in the hopes of eventually getting to an even better local/global optimum - not really traits of satisficing.

 

Satisficing is something better suited to economics and money or modelling human thinking (hence its use in neural nets I guess). But the description given for satisficing IS a good way to picture evolution, if you just ignore the guiding hand satisficing adds.

 

Evolution approaches the optimisation problem of "the best species" using a variety of tools: inheritance, random mutation, crossover, and selection.

 

-Inheritance ensures good solutions (organisms/traits/species/genes, whatever scope we're working with) are handed down.

 

-Random mutation nudges good solutions away from their local optimum just in case there's a better solution somewhere else. This often involves a step backwards to a worse solution, but can sometimes move to similar solution or a better solution. This isn't something planed. It's just how DNA is (when exposed to things like UV, or because the error correction mechanisms miss an error, etc). But life wouldn't exist without this part of the process.

 

-Crossover is used in case two good solutions can produce a better solution when mixed. This step isn't strictly necessary obviously - think bacteria and viruses. It's just an extra stage which helps to find better local optima. Actually bacteria and viruses use a similar mechanisms called horizontal transfer - where viruses and bacteria exchange novel genes. Without something like this your optimal solutions can tend to stagnate at sub-par, even with random mutation giving you a nudge.

 

-Selection is the way bad or lesser solutions are eliminated. Rewarding good solutions increases their fitness compared to the lesser solutions. That is: good solutions are more likely to reproduce. It is not a conscious mechanism, it is simply that lesser solutions die (out) because they ain't sexing as much as something else (which might then steal all their food through sheer numbers), or get killed by something else.

 

As a final note, the "fitness landscape" for evolution's problem of "the best species" is changing. Good solutions may not remain good, and lesser solutions might become better ones. Why is it changing? For so many reasons it's not funny. Broadly, though: because species compete and interact, and because the Earth is in many different equilibrium states which are ALSO working to optimise themselves - atmospheric composition for example.

 

It's kind of like the classic chase scene: You've got a round table, and a crook on one side, and a cop on the other. The cop goes one way to catch the crook, the crook goes the other. The cop changes to go the other way, but the crook anticipates this and also changes. Except instead of 2 entities you've really got billions doing this. But they eventually settle into an uneasy balance and that balance is Earth - but things are still moving around and will continue to do so until something stops the equillibria. It's the perfect example of "order through chaos". It's all tied very closely to complexity theory.

Your knowledge of biology is near flawless I presume, and I apologise for calling you ignorant. But optimisation is not a conscious mechanism. That's the same claim intelligent design proponents claim as a flaw for evolution, and if you can see why their claim is false it's the same reasoning for why optimisation in nature isn't a conscious mechanism. Also, those two examples you just gave are both examples of leaving one local optimum for another. The first uses crossover to jump out of a local optimum in search of a (possibly) better optimum, the second uses mutation to do the same. Although that black butterfly survival example is a fascinating example of microevolution which occurred during the industrial revolution, no?

 

Viewing evolution as an optimisation approach doesn't change anything you've learnt. It simply offers a different perspective into evolution and a newfound understanding of some of the previously mysterious mechanisms and occurrences in nature.

 

Well, we are talking about the same whit different words . Im wondering if the entropy has a role in the evolution chaine...

And yep, it was an example of the industrial revolution era.

 

Very true. Ah... heh.

 

Regarding entropy: indeed I was just touching on that in my reply to Walsh then. If you looked at the laws of entropy you certainly wouldn't expect something like Earth (and life) to turn out as it has... but it really turns out to be a product of the euqillibrium soup which Entropy creates, I guess. In complexity theory it's referred to as something like a "sweet point" where all the equillibria work in tandem to find a solution that suits them all at least partially. Too much complexity and things fall apart, too little and order (life for example) can't form. It's actually related to chaos theory, but no surprise there since we're talking about complexity. Look at structures that form from chaos, such as cellular automata: http://www.bitstorm.org/gameoflife/

 

Somebody has another idea of how life and entropy relate, basically it proposes that life if viewed as a whole, actually works as a force for entropy: http://130.94.161.3/KortExplores/articles/files/entropy1.php

 

I really do recommend the book "Frontiers of complexity". It covers anything discussed in this thread, as well as topics like the human brain, neural nets, physical systems, equillibrium, entropy, chaos theory, self-assembling molecules, cellular automata - anything related to complexity, and it shows how they are all very closely related due to being products of the mathematical notion of 'complexity' (though the book itself uses no mathematics, don't worry).

 

About.com seems to have a semi-sufficient explanation in place of my ramblings: http://atheism.about.com/od/evolutionabiog...s/a/entropy.htm

Edited December 28, 200718 yr by Krezack

Wait, isn't this a thread about crpg/aliens combat? Where is the good groin shot talk?

We need a thread detailing the Alien reproductive system. I mean, some of the drones have to be able to mate with the queen. In most insect societies thats a once in a lifetime deal, where the queen then stores enough sperm inside her to last the rest of her life.