Muscles, Fat, and Chloroplasts

[Numsgil]

As per suggested, here's what I'm thinking for dividing body:

1.  Muscles - High density, low volume, helps increase the efficacy of actions, such as the strength of shots.  Can be broken down for a very small percent of the energy used to create it.  There's a cost field for muscle upkeep every cycle.

2.  Fat - Low density, medium volume, a near perfect storage mechanism for nrg, with little or no cost upkeep.  Works equally well in plants or animals (technically the label "fat" is a misnomer for this reason).

3.  Chloroplasts/Cellulose/Some other plant related term - Low Density, High volume, produces nrg from sunlight.  Little upkeep, but like muscle it can only be broken down for a fraction of its creation nrg.

The idea is to seperate the function of body in such a way that plants and animals can exist in a smoother spectrum, but there's still historic inertia preventing a bot from playing both sides easily.

As an added benefit, we could encourage bots to pick a side by increasing the efficiency of chloroplasts as muscle levels drop, and vice versa.

[Zinc Avenger]

Is there any real need for "fat"? I can't see an advantage to it. In fact all I can see are disadvantages - the cost of the instructions to store and retrieve nrg from fat, the increased size = increased drag, and a time lag between needing nrg and converting it back. The only good thing about "body" was the increased shot power, and that's been proposed to be the domain of muscle now.

The near-perfect storage system for nrg currently is nrg, that has no upkeep cost and it costs nothing to make available for use.

Might it make more sense to not use fat, but instead make the bot's base size dependent on the nrg it has?

While I like the idea of muscle costing to upkeep, that could kill a bot quite easily. Perhaps something like 1% of the bot's muscle is converted to nrg every cycle if the *.muscle is above 100, so the bot has to keep maintaining it.

[EricL]

I would like to avoid things which perpetuate single celledness.  The day is not far away where a 64 core cpu is the norm.  Sims with orders of magnitude more bots will be feasable.  When I think about new features like those here, I ask myself whether it encourages or discourages multibot organisms.

Take muscle.  I think I'm opposed to it as described and would instead prefer simply using nrg directly to increase shot strength.  The reason is that you can imagine the direct nrg methiod encouraging multi-bots and cooperation in that a shooting bot could specialize as a shooter and cooperate with other bots who give up some of their nrg to allow the shooter to shoot very high strength shots that it couldn't otherwise.  With muscle, there is less incentive for cooperation as a forcing factor to gain the advantage of higher strength shots.  There are holes in my argument here, but you seet the perspective I look at these kind of things from.

Chlorplasts I favor as I indicate in other threads.

Fat/body.   I do think a bot should have a nrg storage mechanism.  I'm not sure that should be different than simply nrg itself.   I do think a bot should be able to manipulate it's size and mass.  I'm not sure that should be directly related and/or soley related to the nrg storage mechanism.

[Anonomous Guest Person]

I personally like the idea, but have a few major questions:

What'll happen with -6 shots?
Will bots still die if they have 0 of all three body methods?
What values would an average bot we see today have? (That is, what level of muscle would an average bot start with, and what amount of cellulose would a plant have? 1000?)
How useful will muscle be? What about cellulose?

Also...

Zinc: Basically to regulate high levels of energy. 32000 energy isn't a wild dream for all bots. Not to mention -1 shots won't steal fat, so it provides some additional defense against -1 shots.

Eric: Unless I'm mistaken, I think muscle efficiency would mean that it would merely increase the output of how much energy is inputted. For example, I'd imagine a bot with 20 muscle would have to output a lot energy to be a devestating combatant, while a bot with 32000 muscle would have to spend much less. And your example does indeed have flaws; spending energy into muscle is far more specialization then just having energy, and would be an additional upkeep for the whole multibot. This could allow for some unusual multibots, as well... imagine a musclebot lugging around a fatbot and using it to just store energy! And take shots from behind that it'd otherwise suffer.

Additionally, if we go with muscles, may I add a suggestion into the mix?
Anywhere from three to five sysvars. Maybe even one. Perhaps we could limit this as a simulation option, because having just one of these would allow for more specialization and thus increase the usefulness of being part of a multibot, while five would definately lean torwards singlebots.
Basically, it'd direct the focus of your muscle torwards one action, basically giving that action slightly more benefit from the muscle, but everything else a bit less. Of course I haven't quite worked it out yet, so it might not be all that feasible, but I still like the idea.

[Jez]

Reminds me of pre-body times;

I am all for adding layers of complication to how a bot works, it adds to the variety of bots that can be made.

One thing you always have to remember is it's not us writing the programme, we have our saviours (EricL et al) our saints (PY) and our Gods (Carlos) and it is up to us to convince them that this is a good idea.

Is this a change that that would have a more benificial benefit than other changes?

To quote EricL "I would like to avoid things which perpetuate single celledness"

[EricL]

Just FYI, I don't have to agree with something to implement it.  Many things impact the list of things and the order of my to-do list.  I have my pet projects to be sure, but if there is strong consensus on something, it gets added to the list pretty high...  So don't think discussion is in vain.  It's more a democracy then you might think...  

[Numsgil]

In addition to what AGP said, the largest reason to add fat is that it would be implicitly allowed when a metabolism is set up.  Simply collect large numbers of substances with high free nrg.  Not adding it would just mean it gets added in a round about way later

Fat can be more specialized than current body.  We could have it store 100 nrg instead of 10, or even 500 nrg.

In real organisms, they tend not to use ATP for long term storage solutions because sugars are more compact, they tend to take up less volume/ less osmotic pressure, etc.  If we give nrg a volume, then fat becomes a reasonably way to decrease volume.

[Zinc Avenger]

I like that idea (it occurred to me too as I was reading above only to realise Numsigil got there earlier and posted it before me  ), it is a little counter-intuitive (you'd think a fatter bot would be larger) so perhaps "fat" isn't the best name for it?

In real life muscle has a high cost to form but it is actually more efficient to retrieve stored energy from muscle than from fat once you have already invested in the muscle. So to add another suggestion to the melange: Currently the maximum rate of body increase/decrease is capped. By changing it slightly to make the cap dependent on the "input" substance instead of equivalent nrg you can make muscle slow to form but quick to break down. Like so: 10 nrg > 1 muscle, 1 muscle > 10 nrg, with a cap of 100 nrg or 100 muscle converted per cycle. So the maximum muscle that can be formed each cycle would be 10 muscle, but in any cycle 1000 nrg can be liberated from muscle. Obviously the numbers could do with a little tuning but I hope they illustrate my point.

[Numsgil]

I don't think that's right.  But I'm having a hard time finding anything about this, so I can't be sure.

My basic biology from years ago told me (I think) that the body doesn't burn muscle until its reached the final stages of starvation because the caloric requirements to build muscle are so much higher than the calories you get from burning it.  But I may also be confusing protein with muscle.

Can anyone find a reliable source to get the relative values for real world muscle and fat caloric requirements for building, storage efficiency (in terms of both caloric upkeep and calories stored per mass or per volume), and calories recieved from burning, so we can have a relative idea of how the whole process works in real life?

[Zinc Avenger]

My assertion that muscle is broken down for preference comes from an A-Level Biology course I took about a decade ago so, I am not sure I can back it up convincingly!

The following quote is from The Merck Manual of Diagnosis and Therapy http://www.merck.com/mrkshared/mmanual/sec...chapter2/2b.jsp

Free fatty acid levels rise as fat is released from adipose tissue to provide energy. Blood glucose falls and is maintained at a lower level by synthesis of glucose in the liver from amino acids released from muscle. Plasma amino acid levels rise initially as muscle is broken down but then fall as starvation proceeds, with essential amino acids decreasing more than nonessential amino acids. Plasma insulin is low, glucagon is high, and serum albumin is near normal as long as muscle is broken down to provide amino acids for protein synthesis in the liver. Protein catabolism, in general, decreases with starvation, reflected by a reduction in urinary urea and total nitrogen.

It is not entirely clear above, but it seems that muscle is broken down quite early in the process rather than as a last resort. So I guess it isn't the first resort but it would appear not to be among the last tissues cannibalised for its component amino acids.

My reasoning has always been that high energy density structures are always easier to break down for energy than they are to create. Compare wood with the atmospheric carbon, hydrogen and oxygen that it was created from - its easier to extract energy from wood than it is from an equivalent amount of free atmospheric gases.

While yes muscle is fantastically inefficient as a method of storing energy, it is a very rich source of energy once the effort of constructing it has been accomplished. That's why carnivores require less volume of food than herbivores - muscle (protein and fat) has a much higher energy level than vegetables (cellulose and sugars). I think I'm wandering a little off topic here, so I'll stop this now.

I'm perfectly willing to concede that I'm arguing from half-remembered and misunderstood schoolboy science classes from a decade ago

[Numsgil]

Well now I'm curious.  Let me see if I can dig out my old bio book and look this up.

[shvarz]

Nums, at some point I gave you a metabolsim scheme that had the real biological costs of building different molecules in the body, the energy obtained when splitting them, their relative density and mass.  Look through older messages or through PMs.  I'll take a look at my home computer to see if I saved the file somewhere.

And BTW, Nums is right about muscle being the last reserve.  First goes glycogen, then fat, then muscles.  The main problem with using muscles for energy is that it produces a lot of amines, which need to be coverted to urea and expelled from the body, which is very costly.  So the end gain in energy is pretty small.

[Zinc Avenger]

Shvarz, I bow to your superior knowledge, consider me corrected and one step closer to perfection.

[Numsgil]

BTW shvarz, I looked but couldn't find any PM from you like that (although there are alot to look through).

[shvarz]

Oops, I forgot to look for it.  I'll do it tonight.

BTW, the search is now working!!!

So, here are a couple of discussions about energy and relative sizes of different molecules in a body:

http://www.darwinbots.com/Forum/index.php?showtopic=190&
http://www.darwinbots.com/Forum/index.php?showtopic=98&