Are Americans still evolving?

[hfojvt]

According to a 1983 Biology textbook, "Darwin's explanation of evolutionary change in terms of natural selection depends on five basic assumption:

1. Many more individuals are born in each generation than will survive and reproduce..."

Clearly that is not true for America. In 1939 of every 100,000 people born, 92,435 made it to the age of 20 (which is certainly long enough to reproduce) and 86,650 made it to the age of 40. In 2002 of every 100,000 Americans born 98,672 made it to age 20 and 96,419 made it to the age of 40.

So 86 to 96.4% of the population is living long enough to reproduce, although some will not for biological, economic and social reasons. That defies the first assumption.

The 3rd assumption: "3. Individuals with certain characteristics have a better chance of surviving and reproducing than individuals with other characteristics."

That also seems not to apply. We survive winter cold and summer heat and disease, not because of our biology, but because of our technology and knowledge. Same thing with food, we obtain it economically, not biologically. Thus, social, economic and technological evolution seem to be more important than biological for humans at this point in history, but the rules and processes for that "evolution" are different.

[clydefrand]

1. Don't you think the below statement is a "prediction"??

In 2002 of every 100,000 Americans born 98,672 made it to age 20 and 96,419 made it to the age of 40.


I expect those born in 2002 will be fighting this f---king war in Iraq when they get to be 20! And most of them won't make it to 40 because they'll be killed by car bombs.

[hfojvt]

3. I am assuming they count it backwards

Thus the statistic for 2002 includes people born in 1982. 98.6% of them are still alive, and 20% of people born in 1910 are still alive. Otherwise it should be asterisked * as a projection.

[SpiralHawk]

2. Evolving? Ewwwww - that is, like, so 80s

Get with the program. You are either with (generic entity) or you are against (generic entity).

It's that primal. Get yourself an extreme zeitgiest makeover

[hfojvt]

5. well, 1980 is when I graduated from HS

and it has been down-hill for a while now. Losing more hair and more teeth and more hope every year, but I still have a fair amount of each.

A make-over seems so superficial, even an extreme one using surgery is only changing the outside. What you are talking about is a conversion, or re-programming, or re-conditioning. Just another trip to room 101.

[TahitiNut]

4. "surviving and reproducing"

Survival - (Un)natural selection in favor (greater representation in the gene pool) of "pro-life" as opposed to "pro-choice"?

Reproduction - (Un)natural selection in favor of (greater representation in the gene pool) Tom Cruise look-alikes as opposed to Albert Einstein look-alikes?

:scared: :scared: :scared: :scared:

Evolution occurs over eons, not centuries.

[dkofos]

6. The majority (that aren't too religious) will most likely evolve.

The truly religious are stuck in the 12th century.

[batsauce]

8. I still say the key is reproduction.

Even if you don't like their politics, if they produce more children they win the evolution game. Evolution is much less about "survival of the fittest" than "survival of the fecund"



fe·cund ( P ) Pronunciation Key (fknd, fknd)
adj.
Capable of producing offspring or vegetation; fruitful

[TahitiNut]

10. So, you're saying it's a fecal matter, huh?

:evilgrin:

[batsauce]

7. An Old SciFi story...

had it that since people with the ambition and intelligence to go to college have less children, we are evolving into a dumber species.

(I think it was Pohl)

So even if everyone survives, you don't win the evolution game unless you reproduce.

Clearly, if evolution means anything, When one group starts having fewer chldren, we are evolving away from that genotype. Not that college actually represents a smarter group, but as a group it certainly doesn't produce the number of children per capita as other groups.

This theory, which I believe is taught as scientific fact in Kansas schools relies on 3 assumptions:

1. Evolution actually works. (just because a preponderance of authorities believe something is true does not always make it true.)
2. Whatever makes up the college crowd is genetically based.
3. That the smaller number of actual births results in a smaller number of reproducing children. For instance, even though Bush has only two children, he still wins the evolution game if his two kids survive and he sends all your kids to war. In that case we would be evolving into Homo Bushes.

Isaac Asmimov also had a theory on evolutionary outcomes, but it didn't involve college students.

[hfojvt]

9. not sure about the reference to Kansas schools

but that fits in with what I call "reverse eugenics". Not even talking about college, if you look at the number of children produced by those who were in the honor society versus those who were not.

I think that "intelligence" has more to do with how much you study and how much you value learning than it does with genes, but the group having more children were not known to be studious or very compassionate either. So, it may be socially based, but the next generation does not seem to have a very good environment.

[BillZBubb]

11. Yes, Americans are still evolving.

But, what is happening is beneath the surface and in the genetic variation.

As you pointed out, our technology (and culture) makes many of the classic selection mechanisms insignificant. Therefore, there is no driving environmental factor to cull out specific traits. Virtually all non-lethal traits survive. But, this means the genetic possibilities are increasing. So, the genotype is evolving.

What is needed to see evidence of evolutionary change in the species would be a long period of isolation of a group of individuals without the benefit of a high level of technology. Until that happens, phenotypes won't change noticably.

Perhaps one day a group of humans will colonize another planet and then be cut off from Earth for a few millenia. That might produce some interesting evolutionary changes.