Reproduction vs Mutations

Gameplay
1

What if the player didn’t automatically enter the editor every time they reproduced?

I was reading about sexual reproduction in unicellular organisms, and I saw that certain eukaryotes can transfer DNA without actually reproducing. The same occurs in bacteria (conjugation).

At the same time, organisms reproduce quite a lot and do not evolve every single time, especially in asexual reproduction. But in the current concept if microbes reproduced quickly it would also mean super fast evolution rates.

My idea is, what if we make it so that each time you reproduce, there’s a chance that you will mutate. Mutating means entering the editor. The chance of mutating is summative, so if you fail it increases until you succeed and then its reset.

When starting a new game, the player can choose under “Mutation Rate” how likely they are to mutate with each reproduction. They can set it at 100%, which is the current concept, and it would lead to quick evolution. Or they could set it lower (default would be something like 25%).

This would also mean that we could allow the player to mutate without reproducing. In observed sexual reproduction in microbes, two microbes meet and exchange DNA (aka “have sex”) across their membranes and then part. In Thrive we would allow microbes to do this if they evolve sexual reproduction. The player would swim their microbe to another microbe and engage in the DNA transfer, and there would be a 25% chance that he would enter the editor and if he did he would spawn back in with an evolved organism, but with no reproduction having taken place.

Another example would be in transformation, where a cell absorbs some DNA and integrates it into its own DNA. We can represent this in game by having a small chance to mutate if you ever consume some floating DNA.

2

Isn’t it a bit unrealistic to allow the player to edit their cell when they exhange dna with another cell or pick it up from the environment? Shouldn’t they instead be just given the choice to pick whether they want to incorporate the floating dna to their cell causing some specific effect and with swapping dna with other cells they would be given a list of bits of dna that they could take?

Not always getting the editor is probably not very fun. I don’t think this should be implemented as the purpose of the editor is to allow the player to directly make changes that would have occurred over millions of years and many, many generations. So even if a cell mutated only once every 1000 splits the player should still get the editor each time. Also it would only serve to make the game slower and more grindy. I don’t think the player should have to split their cell (reproduce) more than 10 times before getting to multicellular, otherwise a single playthrough of thrive would take a really long time, and I don’t think we should aim for grand strategy length games.

3

Actually surprisingly no, bacteria and some eukaryotes too are able to uptake DNA and add it to their genome. During this process or the process of exchanging DNA with another cell (called conjugation), mistakes can be made in copying or stitching the DNA and that’s what leads to mutations.

Also yeah, now that I think more about it I think it’s better if the player enters the editor every time by default. I’d still suggest we keep the it as an option in the starting settings though, because I think the alternative could provide for some interesting gameplay (But the default would be 100%).

This raises the question though, what effect do we want conjugation to have? The ideas I have are:

  • Grants a chance to unlock an organelle or agent (same as when you assimilate floating DNA).
  • Takes you to the editor.
4

Or we could give some penalty for not doing it, like random mutations with a high chance of moving organelles randomly, a small chance of having a random organelle deleted, and a teeny tiny chance of having an organelle added, because i feel generous (from the ones you have unlocked ofc, i’m not THAT generous).
The chance of a mutation happening should probably increase with the cell’s complexity, so as to not have a small cell crippled beyond repair because it had its only vacuole deleted by RNGod.

5

Could you clarify what you mean by this? Not doing what?

If you mean to make assimilating DNA and conjugation have a chance of causing neutral or negative mutations instead of just unlocking new organelles that’s an interesting idea.

6

I meant if you dont conjugate for a long time you get mostly malign mutations, having conjugation be some sort of genetic material restoration, similar to what ciliates do https://en.wikipedia.org/wiki/Ciliate

7

Hm, that’s an interesting idea, but even though it’s realistic I don’t think it’s a good idea to implement because I think we should avoid penalizing the player for not conjugating, especially since many players may not evolve sexual reproduction until multicellular. I think it’s better to simply reward them for conjugating.

8

Asexual reproduction has the benefit of being more “stable” genetically. On the flip side of that anything that can kill one cell can probably kill off most of the species in one swoop.
So random mutations I think should be limited to actual replication or the fireball in the sky, via UV radiation (lessened in deep waters).
I think rewarding them for conjugating, and leaving them alone when they don’t, is probably the best way to go about it.
It would suck if a newbie to the game couldn’t figure out why their little bundle of DNA is deforming negatively.

9

What if conjugation simply grants the player more evolution points next time they enter the editor? Also i like the idea of having the option to not enter the editor every time you split

10

I have been thinking about methods of implementing gene transfer in Thrive in a balanced and fun, but also plausible way. I dont know if I am happy with everything I came up with but I’m putting this out here for discussion material.

Types of gene transfer:
As with many aspects of biology, there are many ways cells could potentially transfer genetic material. While I would prefer to have atleast two varieties of transfer for cells to choose from, one method alone could be suitable for this stage of Thrive. A player could potentially select their preferred method within the behavior tab of the editor, or alternatively the methods could be adapted by placing specialized parts on the cell. This method would only be achieveable once per generation to prevent abuse. Among these options, there would be a selection for having no transferal method which would serve as the default adaptation.

Conjugation:
Probably the most well known method of transfer and commonly known as horizontal gene transfer. This is where two cells simply adhere to eachother or form a bridge with pili to transfer genes. In Thrive, I imagine this process to be somewhat hard to achieve, but often rewarding. By pressing the assigned key, the player would enter a transferal mode where they extend a specialized pilus in order to hook onto the pilus extended by another microbe. Once connected the two microbes would need to remain for a short time in order to complete the transfer, otherwise they can cancel the transfer should the need arise at the cost of gaining nothing. During transfer, cells will find it difficult to move effectively, and will be left defenseless should a predator come.

Transformation:
A somewhat lesser known process, transformation is when a cell picks up and integrates loose genetic material into itself. In Thrive, this would allow players to obtain genetic information from the remains of dead cells. However, due to the damaged nature of these genes, the player would only have a small chance of obtaining anything of benefit from this unlike from proper genetic transfer. This method could be adapted as a passive chnage to a player’s engulfment mode where they would abosrb less compounds in exchange for a chance of genetic material. Cells with thick walls would also be incapable of this method. Alternatively, this could be it’s own seperate mode being activated by the same key as horizontal gene transfer.

Auxospore formation:
Actually a method of sexual reproduction, auxospores are formed by the fusion of two cells in order to transfer genes which is seen in diatoms on earth. In Thrive, Forming an auxospore could be done by seeking out another cell when both you and the other are ready to divide, and then merging into each other using the transferal mode bringing the player to the editor. This could be a much safer method than conjugation, however the player would need to be ready for reproduction before starting the process.

Rewards:
Obviously there is a purpose for genetic transfer and while it is rather straight forward in nature, how shall it be in Thrive?

Random free organelles:
One potential reward is obtaining a single free cell part to in the editor which can be used or ignored, the random organelle would be related to the cell you transfered with.

MP discount:
A discount on the cost of parts related to the cell you transfered with, this would allow for more flexibility and less reliance of chance than the above method.

Increased MP:
A flat increase in MP when entering the editor. A rather uncreative but suitable reward for genetic transfer. Would do exactly as advertised, and personally, is my least favorite.

Part discovery:
Should we ever choose to implement unlockable parts, one method of unlocking them could be initiating transfer with a natural cell that possesses the part.

The one issue that bothers me the most about this, is a proper cost to the boon of increased freedom in the editor. I can’t quite come up with anything appropriate other than a high MP cost for adapting the abilities. We could potentially make the processes resource intensive to utilize but that in itself could be undesirable.

11

I haven’t been super keen on the mutations. I like the idea of it just being like a free organelle function that you can optionally use, to give more depth to the microbe stage. But I don’t think this should be major, prioritized feature.

1 Like
12

Commenting here in accordance to my thoughts in the exploration thread regarding lateral gene transfer and in light of recent discussion for a mechanism for discounts: Exploration

I think for the purposes of the Microbe stage, it’s good enough to represent lateral genetic transfer through the mechanism of transformation. I’m using Nick Lane’s “The Vital Question” as a source of information here, where he says that especially for prokaryotes, lateral genetic transfer literarily is almost like a buffet where prokaryotes are able to take up important environmental adaptations like a trip to the groceries. This leads to prokaryotes being incentivized to being even more simple and energy efficient, having only enough genetic material to be able to rapidly uptake said adaptations.

With this in mind, it can be made so that a player finds genetic information (clumps of DNA) floating around the environment they can take up for a discount applied on their next editor trip. This can also incentivize exploration, as commented in the previous thread. And as I said above, this mechanism can serve to be a good enough representation of genetic transfer for the purposes of the stage.