Researchers Say Data From an Island in Quebec Proves Humans Are Still Evolving
nautil.us
nautil.us
There's absolutely no discussion of cultural impact whatsoever as a cause; these islanders were not cut off from the rest of the world; they speak French for goodness sake!
Despite this omission, there's much talk of cultural changes on the island now that tourism is a big thing, so it's on the radar of the journalist.
I just don't understand how you can jump to 'groundbreaking change in genetic theory' from 'birth dates changed'.
I'm not even that against the proposal -- if I look at what selective breeding can do in say dogs, it makes sense to me that environment would encourage rapid genetic changes at times. Fine; but this article neither proves that genetic changes are the cause here, nor even attempts to provide an environmental explanation that could cause such a shift.
I get the goal of writing a story-style magazine science article. I've read my fair share, and executed well, they can make for an enjoyable read.
But this article feels like 50% uninspired travel diary...
Exactly. Could have done with something half the length (and twice as informative).
It's still absolutely the case... it's just that the fitness function has changed. Now evolution isn't testing to see who can outrun a wooly mammoth or sabre-tooth tiger, or survive without food for 27 straight days, or to see who has the strongest immune system. Now it's testing to see who can navigate their way through high-school, get into a good college, choose a valuable major, get a degree, and get a job making beau-coup money. Since it is still the case that those with more money (on average) have more reproductive opportunities, get better medical care, live longer, etc.
All of that said, let's not ignore that the physical stuff still matters as well. Unless a lot has changed in the 20 some odd years since I was in high-school, the jocks on the football team are still getting laid more than most guys. And being bigger and stronger and more physically fit is still correlated with success in the worlds of business and politics. I don't have the reference handy, but I'm pretty sure I've seen studies showing that taller men are more likely to be elected in political races. And having political power, again, tends to lead to more reproductive success, etc.
But I still don't think that any of that would lead one to think that "evolution has stopped". Even if you step back to only focus on what you describe as "the lower educated, lower income" people, there's still competition for reproductive success within that group. If nothing else, sexual selection is still a factor, even if survival selection isn't as much a factor.
Another thing to consider is the "red queen" theory that human evolution and the evolution of pathogens are locked into a (more or less) permanent "arms race". I don't know that anybody knows for sure that that theory is true, but if it has merit, that's another reason to believe that we are still evolving on some level.
The alternative is to actively promote reproduction of the successful... which sounds, quite rightly, like eugenics. It's a nasty paradox.
[1] https://www.youtube.com/watch?v=d43gKl9xIME [2] https://en.wikipedia.org/wiki/Quiverfull
That may be, but evolution doesn't answer to our conscious desires and ideas of social good or progress. It really is just "the blind watchmaker". What we evolve into isn't "good" or "bad", it just "is". Or at least that's the way I look at it.
That's nice. Financially secure people tend to have way less children then the working class/poor. Remember, viable offspring is that which lives long enough to reproduce.
That's a fair point, but then we also have to ask "do they have fitter children in turn"? Sexual selection would suggest that more fit individuals seek out and mate with other more fit individuals, as each tries to maximize the fitness of the vessel carrying their genes. If that's the case, I wonder what the effect of that is, carried over multiple generations. I haven't spent a lot of time thinking about this, and I really don't have an answer, but it's worth pondering.
Remember, viable offspring is that which lives long enough to reproduce.
Just living long enough isn't enough, you also have to be able to attract a mate to reproduce with. I suspect it is the case that in modern times, sexual selection is more of a factor in human evolution than survival selection.
Nonetheless, you guys do make a good point about the wealthy/educated having less children. We humans have complicated things by creating things like birth control and by evolving our thinking minds which (in theory) allow us to override the imperative of our "selfish" genes. :-)
e: i think i meant to say birth control (evolutionarily) negatively affects those with more social power
We should be able to find other species populations that exhibit the same relationship between infant mortality and frequency of birth.
To be clear: do rich and successful people have more children than poor ones? Someone has any source on that?
Two thoughts on that:
1. They almost certainly have more opportunity for mating. But they may not always take advantage of that opportunity (especially since they may have child-less sex through various birth control measures)
2. It isn't just a question of the number of children, it's also a question of the fitness of their children. If "fit attracts fit" then the most fit females tend to pair up with the most fit males, and their children average out as more fit than others.
But now we're back to the idea that we no longer know exactly what "fit" means in this world. I guess the answer is "it's complicated". But I still don't see any reason in any of that, to think that no evolution occurs.
What we are currently selecting for is people who have lots of kids and let society pay for their upbringing.
We're still evolving, even if it's not in a way that would make us better at surviving in the plains/tundra/forest/jungle anymore. It may make us worse at those things (as a species), but better in our new environment (urban, factories, offices).
The definition of 'fittest' is not set in stone.
You can't look at a population today and identify which individuals are the fittest in evolutionary terms. It's not possible to state with precision that someone who has e.g. more sex or more children or is taller or richer or poorer or better spoken or more sociopathic is more likely to succeed.
Rather, fitness is something that can only be defined in reverse, because today's population is full of individuals with ancestors who have survived and reproduced, and so on all the way back.
As Neal Stephenson puts it: "Like every other creature on the face of the earth, Godfrey was, by birthright, a stupendous badass, albeit in the somewhat narrow technical sense that he could trace his ancestry back up a long line of slightly less highly evolved stupendous badasses to that first self-replicating gizmo---which, given the number and variety of its descendants, might justifiably be described as the most stupendous badass of all time. Everyone and everything that wasn't a stupendous badass was dead."
It really shouldn't be (astonishing, that is). As major social, political and educational structures that were, at least in some cases and locations, largely exempt from the greater political upheavals and wars, they should be considered a first choice to search for a lot of data that has to do with human history.
No? I thought that humans used to be all lactose intolerant, and that the ability to digest lactose was a rather recent mutation that's for example more spread in Europa than in East Asia.
To me that's a perfect example of modern humans still evolving genetically.
[2] http://www.amazon.com/Mind-Cosmos-Materialist-Neo-Darwinian-...
[3] http://www.amazon.com/What-Darwin-Wrong-Jerry-Fodor/dp/03126...
We completely screwed natural selection, so I guess bad genes will be creeping into the population for a long time, things like cancer, malformations and genetic related diseases will be blooming like crazy in the next centuries.
Let's hope medicine keeps up with it.
Almost all diseases that happen after a species' reproductive age is very difficult to select out either in a positive or negative way unless it happens to be strongly genetically linked (either through sharing genes or being very close on a chromosome) to a different positive or negative trait. Even then in the long run the survival of that trait will be dominated by its independent characteristics.
The way to flip this around is that you could also look at the "survival" of the disease, disorder, etc. Not that we WANT these to survive, but they either will or won't. If a disease causes death 100% of the time at age 2 and provides no other benefits in the carrier / recessive trait it tends not to last in the gene pool for very long.
Well that's not entirely true. I think humans evolved (and still evolve) on a tribal level. So an individual's traits that strengthen the tribe are also good for the survival of the tribe since one's entire gene pool would be wiped if the neighboring tribe killed all of you, even if the individual is post-reproductive age. I find that most people never talk about evolution on a tribal level like this.
So once genetic desease reaches a problematic threshold (where medicine can not offset it), I'm pretty sure people will begin to talk about their families health history earlier in the mating ritual.
Or test (and select) their embryos if the bad trait was passed on. Or at some point modify them. Which both will lower the spread of bad genes.
it's too simple to regard evolution as something that happens merely on an individual level. e.g. it was always possible that the strongest and smartest human will get killed by a group of physically and intellectually weaker people. does that mean we stopped evolving back then? no, we evolved social behavior, like many animals before us, i guess...