size traits

[Tad Carlucci]

They've hinted at Size becoming a breedable trait for some time now, if I recall. The issue would be how to fairly convert from the present random Size to a genetically-based Size. As to other new traits .. there's been a number such suggested on these forums. And they've gone through adding traits, already (Whiskers and Whisker Shape). Don't know if it went as they intended, initially, but it seems to be running fine now.

When looking at truly random systems, one needs to beware of the pitfalls. First, given enough samples, there SHOULD be various-length runs which SHOULD appear deterministic. For example, there is most likely someone out there who has Bengal Snows which always give Males, or Russian Whites which only give Toys. That person might think, correctly, looking at their limited data, that masculinity and snowiness are somehow linked; but they'd be wrong. The other issue is that, being humans, we're predisposed to seeing patterns where none exist. We'll ignore inconvenient data, even when it's quite common, if that's what we need to do to see our patterns.

If I were implementing Size, I'd use a poly-genetic system. Size, in real life, is not one gene. It's a whole pile of genes which control various parts (think: head size, vertebra size, thigh length, etc) and which, when added up, produce "size". This produces a range of sizes which will tend to be distributed on a Bell Curve.

Human Eye color is much the same, where some alleles control cornea shape, viscosity, melanin levels, etc. I've seen the Human Eye Color chart you posted. I've also seen examples it can't explain, and I've seen other almost-working models. None that I've seen, however, do more than cover sub-sets of Human populations. My personal feeling is Human Eye Color is a combination of poly-genetic alleles combined with co-dominants, with a good deal of linkage thrown in.

The most common example of co-dominance is Human Blood Type: A B AB and O. It's small, simple, well understood, and easy to learn.

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BTW. Eye color is not a color. The only color in Human eyes is Brown (melanin) ranging in darkness. The "color" you see is light refracting through the cornea and fluid, and back-scatter from the melanin in the fluid. Brown eyes people have have low (or high, I forget which) melanin .. there is little refraction or back-scatter so what you're seeing is actually the brown color all Human iris have.