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Comment by nhzmju | Hacker News Reader

I was just about to give up at 70th generation, when the walkers suddenly evolved from 1 to 4 steps in 5 generations.

Currently at generation 120 with 7 steps, looks like it is "evolving" in bursts, with long periods of nothing.

Well it is stuck at 9 steps at gen 400+.

  327	aibobe baeado	948.93

  >> 548   aibobe baeado   1058.76

I wonder if the author got any further. I would say this is close to the limit.

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Falling into local minima and getting rescued by mutations.

It's interesting how I got:

0 Cicebi Bicedi 206.20

1 Cibebi Dibodi 208.03

4 Cobebi Bibedi 208.54

6 Cobebi Bobedi 208.68

8 Cocebi Boaedi 209.53

14 Cocibi Boaedi 310.47

20 Cocebi Boaedi 312.73

36 Cocebi Boaedi 312.85

38 Cocebi Biaedi 312.89

40 Cocebi Bobedi 314.06

58 Cocebi Bobedi 417.71

119 Cicebi Bibodi 522.37

331 Cicebi Bibuei 624.26

And at ~500 generations the champions are still the same 3. I have fiddled with the parameters several times to no avail. I've tried very little mutation probability (1-5%) with low mutation amount (1-10%) but also 75-100 mut. prob with 1-5% mutation amount and any figures in between and nothing seems to make it go out of the local minima.

Is there any way to get out of this? or when this happens in nature the species simply goes extinct or gets eaten by everyone else?

Ah.. seems like I finally got out of it at gen ~530 by changing the amount of champions to copy to increase the amount of gene variation in the pool.

I guess it kinda stuck into an inbreeding sort of loop.

It's quite hard to get any better than 10 or so steps, luck starts playing a major role after a while.

Some gait branches seem to reach a dead-end where any improvement would need to come from a major overhaul of the gene combination instead of small mutations.

The terrain starts to get more variation as the distance increases, so that's another piece of evil against the walkers. :D Maybe I should turn that off.

I've let it run for a couple of days. I don't think I got past 12 steps, but it looked pretty regular walking for a while. :)

I was thinking about writing something similar in C. How long is the genome( bytes/chars )?

The genome is pretty simple, just a few motor parameters for each joint in the body.

3 floats for each joint, to be precise. Then those are combined to set the speed of the motor in each joint on every simulation step.

I tried more complex genomes, but it just takes way too long to get any kind of improvement. It didn't make for a fun casual browser experience. :)

Looks like you've hit an evolutionary dead-end.. exterminate!

I felt bad closing the window.

Welcome to punctuated equilibria.

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