How is modern life impacting human evolution?

Factual Questions
41

This part is already happening and has been continually in flux in the US since its inception. it was not long ago (within the living memory of our grandparents and great grandparents) that the Irish and Italians were not considered ‘white’ and some older Americans still hold some racially based prejudices at least with regard to Italian Americans. Nowadays, marrying an Italian American is a non-event. Not notable at all. 100 years ago? Yeah, that would have been a minor scandal for many/most well-heeled families.

The definition changes to meet the needs of the era (cultural if not genetic evolution!) and has changed within even our lifetimes. Sure, it’s correlated with melanin content but not as strictly as people might think. The definition is not about melanin content (which I find amusing that people still think is relevant) but what our society decides is convenient. Actually, this is coming up now that we have genetic sequencing.

There are a lot of people who get sequenced, hoping/expecting to show they are of primarily Scandinavian stock (which is apparently as ‘white’ as it gets to them) and being dismayed to discover they have ancestry from undesirable countries. How easily their skin burns has nothing to do with the state of ‘whiteness’ in their minds.

42

Education is negatively correlated with how many kids you have, generally more educated people have fewer kids. This is bad for obvious and multiple reasons.

In general there is a sense that more dysfunctional people don’t really plan for life, which means they don’t do family planning, which means they also in general have more kids. Natural selection is rewarding dysfunction at this point.

Also on a national level, wealth is negatively correlated with fertility. Luckily as a nation grows in wealth and education they have fewer kids, but the nations that are unable to reach a per capita income of $5000 or so a year still have very high reproduction rates.

Articles like this say its a problem, but hopefully not as bad as it sounds.

43

Are you linking lack of education with poverty?

Is “dysfunctional” the same as not having access to birth control?

I should also point out that people with extensive educations also tend to start reproducing later in life, when infertility is more of a problem for both women and men.

Biologically, women and men should be having kids in their 20’s, but modern society sends the message that for success you should spend those years getting an education and building a career instead of spending time and resources on offspring. This does have something to do with why the more educated and more well off people have fewer kids.

44

Regarding mixing of ethnicities I often wondered… for example, a child of a European and a Chinese person “looks Chinese” to those of us who grew up mostly surrounded by white people. Does the reverse hold - do such children “look white” to people of Chinese heritage? Or is “white” a blank slate, so to speak, on which other characteristics are added?

(When Meghan and Harry dating/getting married hit the news, I did not even realize she was black (or considered black) until it became a media “thing”. I assumed a lot of people in Hollywood took advantage of tanning beds.)

The thing about education and intelligence is it’s erratic. My parents both went to prestigious universities on scholarships; my aunts and uncles are quite unremarkable. (My step-mother several times made some snide remarks about one uncle being a pig farmer…) Most of the apparently fairly high intelligence people in the world are not noted from coming from a family of brilliant people, but seem to pop up from the general average population.

As for fertility rates - do this with any of the people you know the details about -

My grandmother had 3 children, including my father. Those children had 8 grandchildren. Those 8 grandchildren had 7 great-grandchildren.

My other grandmother, the child of a family of 7, had 2 children. Including me, there are 2 grandchildren, and zero great-grandchildren.

One of my wife’s grandmothers had 2 children. Those 2 had 4 grandchildren, including my wife. Those 4 had 4 greatgrandchildren.

On the other side, her grandmother had 4 children. They had 3 grandchildren, including my wife, then 4 great-grandchildren.

The numbers for steady reproduction are 2 children, 4 grandchildren, 8 great-grandchildren. In my circle of family and friends, AFAIK, few are keeping up in the current generation. It’s only immigration that keeps Canada’s population growing. But it’s a trend all over the First World, and seeping into the emerging economies too.

The linked article tries to point out that yes, high school dropouts have more children, but they are only 10% of the population so more children are offspring of better-educated parents. The obvious question is - to what extent is education reflective of intellectual capability, and to what extent does that rely on genetics? You can start huge debates about those questions, but no doubt some part of education is environment and opportunity.

The other objection I have to the article, is evolution is not about quantities, it’s about differential reproduction - whether those slightly greater level of children in the uneducated then continue to have excess children. Compounding over several centuries, that will mean that the offspring of today’s uneducated will start to dominate - all else being equal. But rarely are social conditions all else equal over centuries, and rarely still are the children of uneducated uniformly uneducated (or the educated’s children always well-educated). Even in medieval times, there was some social mixing going on. HG Well’s dystopia of Morlocks and Eloi separating into distinct groups is extremely unlikely.

45

This is a ill-posed question.

The concept of ‘white’ is itself an import from the West. In most cultures around the world, you are part of the local ethnic group or not.

So, a child of mixed heritage will not look ‘white’ but will look ‘not Chinese’. Likewise, such a child will look ‘not Korean’ in Korea. And the guess would be one parent was likely of European descent. Likewise a mixed-heritage child of Korean and Vietnamese parents would also look ‘not Korean’ in Korea. Actually, even ethnically ‘pure’ Koreans may be told they don’t ‘look’ Korean. Note the remark would not be about not looking ‘Asian’ but not looking ‘Korean’. The idea of a pan-Asian ‘race’ is again an import from elsewhere.

Note that this is true even in the US, though it has evolved (heh) over the years and is prevalent to a lesser degree than in the past. For example, one may have once been accused of looking a bit swarthy. Maybe been asked if one had Jewish ancestors (actually - this still happens today). Or Greek ancestors. Or maybe Native American ancestry. Based solely on appearance and sometimes with negative connotations.

It’s not a blank slate because people have not settled on a fixed definition for it for more than a few decades (and even then with plenty of caveats and exceptions).

46

Even this is not always true - my kids are half-Chinese. Usually white people can tell my daughter is half-Asian (although they don’t often guess correctly about whether that half is Chinese or Korean or…). My son, on the other hand , in the absence of any other clues* is assumed to be South American by almost everyone who is not Asian.

* Like if my husband is with him or the context of knowing his last name.

47

Thanks. That was explicitly what I was asking, is the difference as obvious to other ethnicities? (hence, specifying “Chinese” not Asian.)

Indeed, “passing as white” was usually done by the children of ex-slaves by pretending to be of Spanish descent, and indeed there are (un)subtle differences between European ethnicities. However, distinction is in the eye of the beholder. Anthony Quinn, for example, has been assortedly cast as everything from northern European to assorted Mediterranean and Middle East ethnicities and assorted Native Americans.

The other issue would be, the “melting pot” of North America attracts more and more immigrants for more diverse countries, the variety of the genetic base becomes wider. This raises the question as to whether “hybrid vigor” is a real thing or a myth. Certainly, the widest variety of human genes is in Africa (and gets less differentiated as the groups migrated further out) so adding African genes to the population mix is one of the more healthy things for genetic diversity. And in evolutionary pressure situations, variety is always better to help adaptation.

You have to wonder with more isolated ethnicities, whether “looks like” is due to the area being initially settled by a very small group and everyone is descended from that group, with a minimum of newcomers. However, given the back-and-forth movements of history, genetic mixing has no doubt been a very common thing.

48

Perhaps but we have to be careful of ‘just-so’ stories with evolution (genetic or cultural). For example, there are ethnic Koreans in Japan who have lived there for several generations and could not be told apart without some digging but still there are some who would claim they can be told apart at a glance, partly to justify their sometimes poor treatment.

Tribalism is going to play a large part, whether or not out of norm phenotypic characteristics are involved. Some people will be ‘our’ people even if they look ‘funny’. And others will not be ‘our’ people because they look funny.

49

What about the increase of new ways of communicating? Will that have any effect on the human species long-term? People on the autism spectrum or with other social disorders (or extreme introverts) may have often found it hard to find a mate in the past. But with online dating, texting, email, social media, etc., it’s becoming easier for people that lack a neurotypical communication ability to meet a potential mate and ultimately reproduce.

Could this make us more asocial as a species over time? Could “neurotypical” humans become a minority, or at least less common?

50

Isaac Asimov imagined this in a few of his robot stories. The Robots of Dawn imagines a society where people pretty much live alone surrounded by robots who tend to their needs; maybe only occasionally get together to reproduce. Presumably, this is based on Asimov’s roughly less gregarious tendencies.

it occurs to me that slowly Siri and Alexa are working their way toward this sort of service - basically being your personal Jeeves. it’s only a matter of time before someone has a “The Face Book” or “Hot or Not” app where you rate members of the opposite sex on appearance (or other characteristics) and your personal assistant’s AI evaluate potential partners on appearance, negotiate with their AI assistant, will find tonight’s hookup for you, rent the room, arrange the Ubers, etc.

As for evolutionary tendencies - to what extent facility with communications helps reproduction, who knows? Reminds me of the trope that with more people selecting mates themselves, replacing arranged and socially coerced marriages, that people would start to get prettier. The corollary being that maybe men will become more handsome, but men are not that selective about the appearance of their mate when it comes time for one night of reproduction. Particularly when alcohol is involved.