Death Rate

[Endy]

Where'd everybody go? Seems like this place was abandoned all the sudden...

Wanted to recommend adding in either an optional age limit or a random death rate option. I've, been working with a version that I rigged up to have an actual age limit. The evolution rate is amazzingly fast compared to normal. The death rate basically ramps up the selection process, improving what is actually evolved. Canni's still come about, but the age limit kept them from dominating by becomming immortal, like they do other times.

I'm planning on changing the code again to see what effects a random death has. I thinking that random death may be the true spur that drives evolution on. Provided they have enough time and resources they can adapt to pretty much anything. The one thing they can't out-evolve is a pure random death.

Its pretty amazing to be able to watch the population change completly after just a couple of seconds. I'm also thinking that with a little more area the bots will be able to speciate. It's not precisly the distance that keeps creatures in the real world seperated. More accuratly its the fact that their death rate simply does not support crossing the distance.

[Numsgil]

I think it's been sort of quiet since we don't have anyone actively moving the current version forward.  Though I've been flirting with the idea of starting a fresh version (again ) some time soon.

Random death and age limits are definately good tools to play with.  I think in the latest version you can use Eric's aging costs to create an effective max age.  Random death isn't really do able at present I don't think.  I would be interested in seeing the effects of it on a population.

[Jez]

Have been around just not active.

Isn't random death just adding a dice throw to evolution? Wouldn't suprise me if it caused evolutionary swings but would suprise me if it helped create anything useful. Random death isn't the predator option that was talked about on the forum before, surely it would be as likely to wipe out the useful mutations as weed out the bad.
Like you pointed out, the bots can't out evolve it, so why would they bother trying?

Setting an age limit I could imagine forcing adaptive mutations though.

***

Would be cool to have you back working on a new version Nums', there's a whole flock of F1 bots that seem to have problems...

[Numsgil]

I'm expanding my programming horizons at the moment, exploring new programming methods, things like that.

I might give tie feeding a look since there's been trouble with it.

[Elite]

I've just set up some sims using an age limit (massive instant death age cost becoming active at a certain age) and they indeed seem to work really well:

When I turned up the movement cost, the bots responded within a few hundred cycles and became noticably more conservative with their movement.
When I turned up the DNA upkeep cost, the average DNA length of the bots dropped rapidly. Within a few thousand cycles they had lost a gene or two, merged two other genes into one, and posessed a much more minimalistic genome.

What seems to be happening is that since living very long isn't an option anymore, the bots have to act in the best interests of their progeny or their DNA will die with them when the age cost gets them.

Nice find.

[Endy]

Isn't random death just adding a dice throw to evolution? Wouldn't suprise me if it caused evolutionary swings but would suprise me if it helped create anything useful. Random death isn't the predator option that was talked about on the forum before, surely it would be as likely to wipe out the useful mutations as weed out the bad.
Like you pointed out, the bots can't out evolve it, so why would they bother trying?

While the max age limit it will kill off both good and bad mutations, it kills off the decendents of bad mutants more than the good.

P.S.
Is .age updated every cycle? When the condition was just .age = MaxAge Some of the bots managed to skip past it. I had to use a greather than rather than the equals because of it.

[Numsgil]

.age should update every cycle to a max of 32000 I believe.  It some bots aren't, it's probably a bug.

[Testlund]

Sorry, but I find random death horribly unnatural. When something die in nature it's allways because of a slight weakness, wich gives space for the better evolved.
In reality single cellular organisms doesn't age. They live as long as there aren't any predator that catch them, lack of food or environment change.
But because of computer limits it had to be put in, and the best way to go imo is the current ageing cost. I see it as when they grow older the bots metabolism gets weaker and they have a harder time using the energy they consume. So in a way it's kind of natural. I have costs set to increase very slightly every cycle from immediately when the bots are born, not set to just kick in at certain time for no reason.

I take a peak here from time to time, but the program runs smoothly and my sim is rather boring at the moment, so there isn't much to say. The computer where I run it is just standing on a table in the livingroom running the sim around the clock, been running for months now, 28 million cycles, but the bots just floot around multiplying, while I'm busy with other stuff on my computer in the bedroom.  

By the way, you haven't abandoned the version of DB you worked on, Nums, have you? I would like to see that finished some time.    

[Numsgil]

Sorry, but I find random death horribly unnatural. When something die in nature it's allways because of a slight weakness, wich gives space for the better evolved.

I've always thought of random death as sort of localized chaos theory.  From a genome's point of view, random death means it has to spread out its eggs over multiple baskets.  In real life, I'd say death is mostly governed by raw accident and chance, with fitness only playing a minor role in the short run.

Aging costs are less realistic, but I think they provide a necessary house cleaning from time to time.  It's a common feature in other Alife sims too.  If nothing else they compress the time window for organisms.

By the way, you haven't abandoned the version of DB you worked on, Nums, have you? I would like to see that finished some time.    

Not abandoned.  I'd like to pull out various ideas from it.  But I think that a C# version is the way to go.  And I'm also experimenting with more modern programming techniques that help curtail bugs as you go.  And I'd like to really overhaul just about every major system.  I'll come back to it when I feel confidant that I can do it properly start to finish.

[Endy]

Sorry, but I find random death horribly unnatural. When something die in nature it's allways because of a slight weakness, wich gives space for the better evolved.

I've always thought of random death as sort of localized chaos theory. From a genome's point of view, random death means it has to spread out its eggs over multiple baskets. In real life, I'd say death is mostly governed by raw accident and chance, with fitness only playing a minor role in the short run.

Yeah, that's my thoughts exactly. Kind of disturbing to think about, but even we have essentially random accidents occur. We and evolution can figure out most of the probabilities involved and take precautions and preventative measures but we still can't eliminate every single thing. I do wish we had something that could at least be said to cause it to occur, like localized weather paterns or something.

[Numsgil]

How about "Finger of God".

[Martian]

Maybe a splash of disinfectant?

[Testlund]

Or just pretend you're sticking your thumb in there to squeeze them to death.  
When I think about it, we humans cause random deaths here and there in nature which I find somewhat unnatural, but at the same time maybe a few creatures adopt to that too.

[Elite]

How about using waste for the aging death. You could have accumulating waste sap energy from bots proportional to the amount present (a new option in the costs form: "Waste cost per cycle").
I like the idea of waste being a mutagen too, increasing the probability of point mutations as it builds up (possibly a tickbox: "Mutagenic waste")

Sexual reproduction too, even if it were ultra-basic (ie. take every other base pair from each parent) would be interesting to have, and may be another element to have an acceleratory effect on evolution.

Random death would presumably be a slight selection pressure towards collectivism, although multicellularity at present seems to be too complex to evolve.
As for a mechanism: How about "fuzzying" the costs a little. A bot might be "charged" a little more or a little less than the standard cost. Rather than being definite rates, costs would be more probabalistic, like mutations, with a standard deviation from the average value.

[Testlund]

A cost that increase waste would probably cause all bots to go crazy doing all things not written in the dna because of altzeimers, a complete chaos on the screen. Ageing should only make it harder to survive I think.