I was doing some worldbuilding and I began to run into a roadblock concerning giving my races distinct visual...

I was doing some worldbuilding and I began to run into a roadblock concerning giving my races distinct visual appearances and cultures.
How long does it take for separate individual populations to become visually distinct from each other? In short, how long does it take a population to "racialize" due to environmental and social pressures while isolated from other populations. Obviously a cultural shift can happen in less than a generation, but how long does it take for obvious visual characteristics to emerge in a pre-industrial hunter gatherer society?

Other urls found in this thread:

sciencemag.org/news/2015/04/how-europeans-evolved-white-skin
scientificamerican.com/article/when-incest-is-best-kissi/
nature.com/nature/journal/v512/n7513/full/nature13408.html?foxtrotcallback=true
twitter.com/SFWRedditVideos

Probably about 1,000 years at least.

You can start getting a few distinct features pretty quickly. Nose shapes, for example, could diverge amongst separated small groups just by random chance, rather than any evolutionary pressure. But things like the Asian double eyelid would take a long time.

Introduce drastics events like mass death and thing could start to change rather rapidly. If most males die off from tribe B (which is separated from tribe A for some reason), and by a freak occurence most of the few survivors of tribe B are redheads, then you'll see tribe B very quickly becoming visually distinct from tribe A.

Why did people first start cooking food?

Common theory is that they just put it next to the fire to thaw it out and that's where cooking originated

Thawing food in africa?

Africa has different climates in it.

Well, no. It probably would have been a thing after humans had moved to colder climates and spread out from there

But using fire to cook came before humans

Well then it was whatever hominids moved out of africa before them then

sciencemag.org/news/2015/04/how-europeans-evolved-white-skin

With magic, only a mere moment!

Assuming you have generation change each 20-25 years AND migration is taking place, you need somewhere between 5 to 8k years and ability to move over land that is/will be diverse itself.
Best case scenario - hunters entering Alaska via landbridge that is now Bering Strait.

And you can still quite easily trace similarities between Siberian tribes and Indians, getting gradually less prominent and obvious the more south you go.

Ever occured to you stupid shitheads that climate changed "a bit" in past 600k years? In that period we had Mindel, Riss and Wurm glacial period, along with inter-glacial ones.
They don't teach about ice age in American schools or something?

Depends on selection. Dogs, for instance, can have new breeds created quickly IF YOU SELECT FOR IT.

If you are just talking passive, it takes a long time. But if you have pressure for one particular phenotype, you can make it pretty fast.

Given that the average white American looks distinct from the average white Englishperson, apparently somewhere less than 250 years.

However, the more dramatic the visual distinction, the longer it will take.

You know stabilisation of desired traits is achieved with use of inbreeding and often leads to emergence of undesirable traits on the flip side, right?
They are funny of they are something as trivial as the tail getting all spinny, but they also do tend to affect mental capabilities pretty hard.

Your point being? Do you actually think the whole earth is covered in ice during glacial periods? Even at the peak of an ice age africa free of ice with the exception of places with high altitude

>Given that the average white American looks distinct from the average white Englishperson, apparently somewhere less than 250 years.

There has been quite a lot of interbreeding in the US, to the point where "ethnically pure" features are rarer than mixed features.

For example, I am the descendants of Scots-Irish settlers, mixed with Comanche and French Huguenot, and I have brown hair, a widows peak, and yet apparently look extremely Slavic.

My girlfriend is mixed Mexican, Irish, and Black American, but her name is Lasalle.

This is normal shit in America.

mixing with inferior races may have become common enough to be considered normal, but it's still degenerate and decent people will rightly look askance at you for it

>Fire scared away predators
>Upright apes figured that out
>Coincidentally, scavenged meat put near a fire made it safer to eat
>Suddenly meat goes from social currency to full-time food source

Homo ergaster is the earliest species known to have definitely used fire.

You're right, we should all just fuck our first cousins like the enlightened European master race. At least in Appalachia they have the excuse of "literally nobody lives in fucking Appalachia."

>and decent people will rightly look askance at you for it

We literally do not care what y'all think.

Not even him, but you really must be dense.
Lack of ice doesn't mean it was already 40 Celcius. So while Africa wasn't covered in ice (we wouldn't recover so easily from an ice age reaching that deep toward equator), it was considerably colder, especially during Mindel glaciation (the biggest one). This is the one that allowed formation of glaciers on Mt. Kilimanjaro - it was cold enough that a mountain so close to equator could generate glaciers from snowfall. And each 1 cm of thickness of glacier means a residue of snow 110 cm thick and not thawing for entire year.
So go fucking educate yourself, rather than asking what's the possible point.

Are you high on your own farts or something? Re-read the chain of replies you dumb motherfucker.

>one of the westminster dog show "prettiest" winners, an afgan, drowned in its own water bowl because afgans are so fucking stupid.

>hybrid vigor is bad
go fuck yer mum

Hybrid vigour is a myth

race is a myth

>hybrid vigor is a consistent phenomenon
Mate, people of "mixed racial background" have about an 18% higher rate of mental illness. Things aren't always that simple when it comes to shit like genetics when you're dealing with recessive genes hidden for generations and other bullshit.

Well ya see the mglooktook tribe set up a fire on a cold night and were having dinner around it when that dipshit tlork dropped his haunch of meat into the fire, they realized that shit didnt smell too bad and poked it out with a stick,brushed it off and ate it anyway.

>made it safer to eat
Did they use their water-basin microscopes to see that the Tiny Demons were killed by the heat?

He's right tho.

You realize you have just contradicted yourself?
>definite chance
>Oh no, it isn't that easy
So you, the number is most likely bullshit.

Maybe some very broad distinctions can be made within 1,000 years, but I really don't think we can get to our present-day diversity without at least 10,000 years.

How so? What's the relation between glaciers forming on the Kilimanjaro and thawing food in africa?

>What's the relation between being so cold glaciers could form and the fact food could be frozen
Are you genuinely stupid, or just trying too hard?

Accident. While bushfires killed some animals, humans started to salvage the burnt corpses. Than humans started to protect small portions of these bushfires. Through this they learned how to start the fires.
Thats at least another theory.

>For example, I am the descendants of Scots-Irish settlers, mixed with Comanche and French Huguenot, and I have brown hair, a widows peak, and yet apparently look extremely Slavic.
I think the biggest and best study when it comes to America is Amish population. They've literally started from a group of 300-350 people and breed ONLY within that group. While this gave them enough congregation members to avoid outright inbreeding and once in a while a new member (note the use of singular form) was added to the pool, they've started with extreme genetic bottleneck. And it just happens they have a high chance for certain metabolitic diseases that are genetical in nature and are normally very rare. Not because of inbreeding defects as such, but because the initial population was extremely small, so in few generations almost all members were genetic carriers of those ailments, despite there might be just single carrier in the initial group.
In general, small, isolated or self-isolating groups are fantastic source of data about genetical diseases and their passage in population, especially if given population has a tradition of listing their descendants (usually related with small population and as a mean to avoid inbreeding, like Icelanders and their extensive family trees)

Dont fight. Even now in deserts the night can get very cold at night that you need fire.
Besides humans might used fire for protection against animals. A campfire will scare away animals in the night. If you need heat, human will more likely wear leather.

Oh, so I guess africa was hit by an ice age less than two thousand years ago. Because that's when some of Kilimanjaro glaciers formed.

There are eight (!!!) major theories about the importance and reasons why fire was implemented in the first place, only two are contradicting with another theory and they are all considered valid by modern anthropology.
We literally have no means to prove any of them as "the one".

Oh, so you are genuinely stupid.
Good to know.

I agree with this. 1000 sounds too short for a distinct feature past all have red hair or are shorter.

It depends on three factors:
- starting genetic pool (mostly size of it)
- presence of "desirable" (in sense of the existing pressure) features in starting pool
- environmental pressure as such
And despite it sounds like a crazy value, 1k years is a perfectly valid time lenght for numerous features to emerge.

The stronger the pressure and smaller starting group, the faster things will snowball. Add to that "explosive" growth (so a 2+5 families being a norm) and you can speed things up even more.

Indeed. The fossils or sign are too thin to make one theory the real one. Its mostly guessing.

What a nice, compelling counter argument, with a terrific reaction image. Thanks for teaching me that snow on a high altitude location means a whole continent was cold enough that food needed thawing.

But 1k sounds only good for very isolated population.

>Because that's when some of Kilimanjaro glaciers formed.

North western and southern/eastern Africa have significant mountain ranges and highlands and at higher altitudes, alpine climates. Barely gets about 75 even at the hottest parts of the year.

It's not all tropical desert, plains, and jungle.

>You're right, we should all just fuck our first cousins like the enlightened European master race.
I don't think it is really anything close to common here.

But yeah, feel free to take a hint from the enlightened European master race :^)
Some studies seem to indicate that the sweet spot is third to fourth cousin, if you are looking for reproductive success. ( scientificamerican.com/article/when-incest-is-best-kissi/ )

That's why I mentioned the importance of small initial group, which by default means isolation.

Sigh... I'm going to regret this.
Look, you fucking high school drop-out. Get a fucking map of Africa. Find Kilimanjaro on it. Find equator then, it should be right south of it ("below"). Equator is by default the place with highest temperatures, due to the angle between the planet axis and nearest star. In our case - between Earth's axis of rotation and Sun.
Now, what temperature do you need to get snow? Water freezes at 0 Celcius degrees. Snow theoretically can form at 2 Celcius. But as already noted, to form a glacier, you need snow to lie down without melting (simpler words for you) all year round. That means a yearly temperature NOT rising above 0.
Now altitude helps here a lot, since with each 100 meters above sea level, the temperature drops by 0.2 Celcius (usually 0.15). Mt. Kilimanjaro is above 5.5k meters (5.510 to be precise), but surrounding area is at 600 meters above sea level, giving difference of 4900 meters. To simplify things even more, let's just assume 4000 meters of difference. 4000/100*0.15 = 6 degrees and for 0.2 drop of temperature it's 8. Let's take average of 7.
So between the heigh where glacier starts and rest of the area is placed there is a difference of 7 degrees, Celcius.
Thus, by simple equation, when it's 0 degrees at the area with glacier, the flatlands around have 7 degrees Celcius. And this is the absolute minimum situation for the glacier to grow at all. Minimum. The most optimal temperature for glacier growth is at -1.3 Celcius. That would mean the temperature "down below" would be around 6 degrees Celcius

Shall I continue, or you see how fucking chill it was around Kilimanjaro when the fucking glaciers formed?
And this is extremely simplified equation and logic pattern, so your half-dead brain can follow.

This shit is literally taught in elementry school. How early you stopped your education exactly?

>This shit is literally taught in elementry school. How early you stopped your education exactly?

not this shit on my /tg

REEEEEEEEEEEEEEEEEEEEEEEEEE

Yeah I've never been able to really process it myself. It's either:
> Look at me outing myself as an ignorant hateful biggot/racist on the internet.
Or
> Look at me posting this garbage, it's so funny that people are going to be mad at this awful statement of bigotry/racism.
Either way you're showing yourself to be an asshole for no real gain. Why not just choke on your own horrendous existence and die in a hole instead?

The current discussion in anthropology regarding the various phenotypes of humans and their attributes centers on what admixture of archaic humans make up their genome. Modern humans haven't been in their various regions long enough to have such extreme differences in phenotype selected for. however, the archaic humans (Neanderthal, denisovan, heidelbergensis, and probably others that haven't been isolated or identified yet) had been in those regions long enough.

nature.com/nature/journal/v512/n7513/full/nature13408.html?foxtrotcallback=true

So the various phenotypes or races of human living in the world today are more a product of what combination of archaic humans make up their ancestry than how long the current version of human has lived in those regions.

Current estimates are minimum 20k years to start seeing a phenotype region selected difference without migration, introgression of foreign DNA, or abrupt mutation. In reality, its closer to 80-100k years to see significant racial differences. Modern humans just haven't been in their respective regions long enough to create such a broad spectrum of phenotypes.

Hence why the current discussion is surrounding what archaic Homo sapiens make up their ancestry.

Different user adding to this - Homo Sapiens Sapiens dates no more than 50k years aback. We, as a species, don't exist for long enough in ANY region for this to took effect

You do realise that, while that's some fine information you're providing, OP was talking about minor traits due to the oddities of genetics as seen in modern humans and not major physiological differences cause by evolutionary pressures?

What would you classify as minor? Skin tone? Eye color and shape? What about hair follicle cross section and therefore appearance?

Im talking about those "minor traits" you're referring to. The difference between an East Asian person (let's say Han ethnicity for example) and a West African (let's say Bantu ethnicity for example), is not because the modern versions of those phenotypes have been in those locations long enough, but because the admixture of archaic Homo sapiens that make up their respective genetic heritage is actually quite different.

Yes? That's what I was saying?
That OP seemed to be after the time frame for those oddities to surface not the time frame for environmental pressures to induce statistically significant shifts?
Anyway I do love me some genetics talk. Please go on.
Please?

>equator has the highest temperatures
Stopped reading there.

"How long does it take for separate individual populations to become visually distinct from each other? In short, how long does it take a population to "racialize" due to environmental and social pressures while isolated from other populations. "

Without the introgression of foreign DNA, migration, abrupt mutation, and without inbreeding (assuming said isolated population is large enough to be susatainable or grow without that risk), 20k+ years. More realistically, for one race to look significantly distinct from an appearance standpoint, we're talking 80-100k years. Again, without significant introgression of foreign DNA from another population, abrupt mutation, inbreeding issues, or migration (kinda ties into the first but also independent too).

With domesticating dogs from wolves, you see distinct changes in four generations. You see much the same in domestic foxes.

But he's right thou - again.
The area between equator and both tropics has the highest temperatures and in case of Africa it in fact gets hotter the close you get to equator.
It's like you try to nit-pick based on "world" argument, while not knowing about local variable. No wonder you can't co-relate ice ages and glacier formation with being cold in general.

Unnatural selection is very fast. Especially with animals that breed at age 2 and have multiple offspring per oregnancy. 5-10 generations for significant differences. Natural selection is very slow, when one, maybe two offspring per pregnancy at an average reproduction age of 18-28 depending on the region and culture.

>>tumblr
>>/qa/

>without abrupt mutation
>without inbreeding issues
>without migration

So right from the get-go we're throwing out the actual real-life scenarios that lead to the founding of separate human populations, and the emergence of distinct genotypes within those populations.

Most out-of-Africa founder groups experienced pretty extreme population bottlenecks, and most "visually distinct" populations became isolated due to migration. Abrupt mutation is also evident in these populations, as with the emergence and spread of blue eyes in Europe.

...

No, they just noticed that the ones who ate Cooked Meat got the shits and whatnot less often then the ones who didn't.

>For example, I am the descendants of Scots-Irish settlers, mixed with Comanche and French Huguenot, and I have brown hair, a widows peak, and yet apparently look extremely Slavic.
>My girlfriend is mixed Mexican, Irish, and Black American, but her name is Lasalle.

>Americans

About ten generations.

Geez. No secret really, "perfect purebreds" are always rife with tons of problems.

Since I've had a couple and a couple breeds, the ridiculous hip displasia of German Shepherds.

The fact that perfectly bread English Bulldogs are so fucked up, natural birthing is impossible due to being selected for the narrow hips that "hurr durr makes it a bulldog."

Just get mutts people, they'll do better and not break you with vet visits.

>>Americans

The entire point is that we're a bunch of mutts who often have names that are at odds with our actual ethnic lineages, and those lineages largely are irrelevant in our day to day lives.

Both us identify as "Americans," not as anything our ancestors were, nor do we care what our ethnic origins actually are - but we're also not ignorant of our ethnic origins.

Fun games to play here in Texas: "Are they Native American, or do they just have one Asian grandparent?"

That looks like a closeup of someone's ass from the thumbnail.

Create a series of dramatic magical events that shaped the racial diversity in your world and real-world evolutionary biology won't matter. If you want an utterly realistic world, making demi-human races probably won't work very well. This way, you also individualize your setting and make it uniquely your own.

>look at the filename