Tuesday, 17 April 2012

Eliza and Stumpy - A Case Study

With a little bit of prompting from Jessica of Discover Albia, I decided to try my hand at analyzing the genes of Eliza and Stumpy mentioned in my previous post. Unfortunately I don't know a whole lot about Creatures genetics, but I found the experience fascinating and hope to continue to learn more.

The first creature I took a look at was Eliza. Eliza does not walk, interact with, or pick up other objects. I wasn't sure what was causing Eliza's paralysis, but a look at her genetics seems to indicate a problem with the Decision and Concept Lobes in her brain. Using D-DNA Analyzer, I found this mutated gene in her Decision Lobe:  

120 Emb B MutDup Lobe #= 6 State Rule: state PLUS type0 MINUS type1 0 <end> <end>, WTA= 1

The "0" in red indicates the mutation in Eiza's Decision Lobe. The healthy gene in Eliza's mother looks like this:

120 Emb B MutDup Lobe #= 6 State Rule: state PLUS type0 MINUS type1 <end> <end> <end>, WTA= 1 

Unfortunately I do not understand fully what this mutation means. However, it seems that this gene relates to how a creature makes decisions. The "type0" and "type1" segments refer to the two types of dendrites that a creature can process. Here is a quote from The Creatures Developer Resource that explains this concept much better:

"The type 0 dendrites link from decision lobe cells to the 128 concept lobe cells indicate that that particular decision is good if those particular concepts are active. This means that if the concepts become active then the norn will be more likely to choose that decision over other decisions.

The type 1 dendrites link from decision lobe cells to the 128 concept lobe cells indicate that that particular decision is bad if those particular concepts are active. This means that if the concepts become active then the norn will be less likely to choose that decision over other decisions."

From what I can gather from my remarkably limited knowledge, this gene affects how Eliza is able to make decisions. The code adds and subtracts the total amount of dendrites from her current state so that she can select the best action to take. However, the extra "0" in the code seems to be affecting her ability to do so. This can be seen in-game by taking a look at the Science Kit:

All of Eliza's decisions are constantly stuck in the exact same location, which I presume interferes with her ability to select any one action over another. Again, I am not certain if my presumptions are accurate or correct by any means, but this is my theory based on what I have seen so far. She also has a mutation in the Concept Lobe which looks like this: 

122 Emb B Mut Lobe #= 8 State Rule: anded0 <end> <end> <end> <end> 0 <end> <end>, WTA= 0

Unfortunately I was unable to find much information on how the Concept Lobe functions, and I'm not sure if the "0" is applied to the calculation or if it is ignored as it is placed after several end statements. However, the "anded0" statements refers to the type 0 dendrites. It is explained from the Creatures Developer Resource as such: "If all type 0 dendrites are firing then this will be the value of the sum of these dendrites. If any of the type 0 dendrites are not firing then this value will be 0."

Because the type 0 dendrites indicate whether a decision is good, the "0" in the code (if it is being calculated) may be affecting the brain's ability to calculate the value of "anded0" and thus Eliza's ability to determine whether any action is good. However, if what I understand from reading Discover Albia is correct, then the state value rule should end once reaching an end statement, ignoring any variables that occur afterwards. If this is the case, then the "0" would be ignored and this mutation wouldn't be affecting Eliza. So in conclusion, I really don't know what this mutation is doing, if anything.

The second creature I'd like to take a look at is the grendel Stumpy.

Stumpy had an interesting mutation that caused him to run in fear whenever he saw another creature. Closer inspection indicates that he has a severe problem with his fight-or-flight genes located in Reactions:

336 Emb B MutDupCut 1*Collapsase + 1*Fear => 1*Anger + 1*<NONE>; half-life = 32.

Collapsase is Stumpy's "flight" chemical. Collapsase converts a creature's anger into fear, which activates the flight response and causes him to run. The chemical for "fight" is called Turnase, which similarly converts fear into anger and stimulates the creature's fight response. The problem here is that Stumpy's Collapsase gene is converting fear into anger, instead of the other way around.

The second problem is that this isn't a mutation with the Collapsase gene, it's actually a mutation with the Turnase gene. Stumpy's gene should look like this:

336 Emb B MutDupCut 1*Turnase + 1*Fear => 1*Anger + 1*<NONE>; half-life = 32.

Because of this, Stumpy does not have the gene that should stimulate his fight response. In addition, Stumpy's second Collapsase gene is actually working correctly, so he may actually be simultaneously converting anger into fear and vice versa. I'm not sure if both Collapsase genes are active, or if one is overriding the other, however. But because grendels, (or at least this breed of grendel) generally feel anger when seeing another creature, that anger creates fear for Stumpy. He is constantly both angry and fearful while in the presence of other creatures, which activates his flight response.

In related news, I have moved Stumpy and Winter into a new, unpopulated world. Almost immediately the two grendels kiss-popped, and I am looking forward to taking a look into the genetics of Stumpy's children.



  1. That's very interesting! I thought that a 0 after the other state variable rules would have no effect, especially because it's not like it's being added or multiplied to the value. That screenshot shows it perfectly, though: Every decision is equally as important (or unimportant)!

    Is she able to experience reward and punishment?

    The second mutation should have no bearing: Once a state variable rule hits a value of end, everything beyond it is ignored. Having a variable beyond the first end tag mutated has been pretty common for me: As you probably know, though, it's usually pretty obvious when a brain lobe mutation has an effect!

    Stumpy's mutation is also pretty interesting: It certainly explains his inclination to run away! He looks a bit terrified about becoming a father... Now is the right time to run away! Ha ha!

    1. Ah, that's what I thought about the second mutation, but I wasn't completely sure. Thank you for the clarification!

      And Eliza is able to experience reward and punishment, though it doesn't seem to affect her ability to make decisions at all. Also I believe you may have been right about her life-force jump being a bug, (or an oversight/false observation on my part). I have been unable to re-create it in any form, and the COBs don't seem to be the problem either. Ah well.

      I've discovered another unfortunate side effect of her mutations. If Eliza falls asleep, she is unable to wake up again. (Fortunately I have an export file of her before she fell asleep.)

      Poor Stumpy, things just keep getting worse for him! His son, Fig, actually has a mutation similar to your Dwyvach, who feels fear when boredom levels increase too much. Instead of fear, though, Fig sets off his Overcrowdedness drive, causing him to run away! The funny part is that his boredom increases very rapidly when left alone, so the easiest way to make sure he doesn't feel overcrowded is to actually keep him around other creatures. Including Stumpy.

      Oops, sorry for the long reply! It seems I may be getting a bit carried away!

  2. I just did a study to determine which of Eliza's brain mutations is responsible for her problems.


    It's the Decision Lobe mutation.

    1. Ah, thank you for taking a look Ettina! I had wanted to do a similar test to confirm, but was unable to due to some issues with the Genetics kit not liking my version of Creatures. So that really helps! :)

    2. Yes, I had the same problem. I ended up overwriting 'gren.gen' with the genome of my choice and letting the grendel mother make my norns for me.