n interesting article I read recently has a number of scientists debating whether or not human evolution has stopped.  The article doesn't really go into much depth about it, but I will.

First off, I'm not even going to entertain the concept of non-evolution.  No one with a modicum of scientific knowledge believes that for an instant, unless they have so much religious indoctrination that they can't overcome it to see reality, in which case they are to be pitied, and hopefully kept away from children.

If you know better, but just can't overcome your need to continue clinging to whatever organized religion your parents raised you in, you may continue reading.  Most people are like this.  They realize the absurdity of the Adam and Eve Garden of Even creation myth, but aren't comfortable with the pure science of billions of years of evolution leading to humans, so they keep some vestige of creationism by saying that God created the universe and set things in motion, or created the processes that allow evolution, etc.  On the other hand, if you think the earth is 8000 years old and Noah's Ark is really up on some mountain somewhere, and dinosaur fossils were put in the ground by God to fool heathen scientists, you might as well just skip the rest, since it'll all go way over your head.

So has human evolution stopped?  

It's certainly possible, since as the article points out, much of natural selection (in humans) has been ended, with so little early death (compared to the good old days), and especially monogamy, and societal reasons for it. In animals, the dominant male might be the father of 50% of the young, since he'll claim as many females as he possibly can, by violence, if necessary.  Weaker females will die, or have fewer/no offspring, while stronger females will have lots, and raise their young to be strong and healthy, thus perpetuating the cycle.

For humans that happens a little bit, perhaps more in some of the more "backwards" cultures like Arabia, with multiple wives, and god knows what's going on with "savages", people living in mud huts and praying to rocks and such in various 3rd world portions of the globe, but it's not a common thing.  Humans are almost never truly monogamous (we like to fuck around on the side too much), but even with rock stars and athletes and other males that score aplenty, they don't tend to have *that* many children, and seldom does one man dominate the reproduction of multiple females.

One could argue that in our western world we're actually going backwards.  Who has the most kids?  Usually poor people, who can't afford to give them the best care/education/etc.  Hard to discuss that w/o sounding like a white supremacist though, raving about the black or brown menace.  After all, plenty of white trash women get knocked up at the drop of a welfare check, right?

More seriously, the dominant factor in human success now is technology and intelligence.  These, along with a minority (pun intended) who succeed financially through athletic ability.  However this doesn't often translate to the old fashioned evolutionary gain, which was achieved through sheer numbers.

In other words, in the old days of humans, and currently in most animals, the male with the best attributes of choice (generally strength, speed, size, etc in animals) gets to breed the most, and has the most offspring, thus passing on the most of his genes, and therefore having the largest effect on the future generations.  Weaker, smaller males don't get to breed much, if at all.  Therefore the tendency is generally for animals to grow ever faster, stronger, sleeker, and perhaps somewhat more intelligent, or at least to weed out the really stupid, since they'd not be clever enough to catch their own food or stay away from predators.

That's an oversimplification, since it ignores animals that are monogamous, others that have a social structure that might support weaker or dumber animals, species where females have more choice in who they mate with, but you get the picture.

In humans now the physically strongest don't necessarily get any special success.  How many ex-football stars in high school and college are working in gas stations, or coaching P.E., or in jail, etc.  Compared to that, weaker or smaller males often spend more time with their studies, and end up with much better educations and better jobs, and more money.  And individuals with both, physical strength and intelligence, are often the most successful, beating the slightly stronger but dumber males in sports, using their physical skills and good looks and confidence to beat the slightly smarter nerds in getting jobs or leadership roles.

But none of this necessarily translates into more offspring, or even offspring at all.  As I said a few paragraphs up, who has the most kids generally?  Poor people, where they have less intelligence to use birth control, more free time, less to occupy themselves with other than sitting around and watching TV and screwing, and more miserable lives, where they need to find some joy and often turn to drugs, drink, sex, etc.

However education and culture eradicates much of this, since even very poor children survive thanks to free food and medicine, and can often work their way up with education to be as or more successful than more fortunate kids. Humans today (in Western culture) are much more fluent in technology, more mobile, have better standards of living, and would likely appear much more intelligent than their great grandparents.  However they have identical genes.  Check back in 200 years, will everyone learn computer programming and interfacing in pre-school?  Will everyone know how to plot star coordinates to fly their ship across the Milky Way?  Will almost no one have any idea how to plant a field, or fix an engine, or make a fire, since we've got machines to do all of that?  There's no way to say.

This is all basically off topic though, since evolution isn't change in an existing organism.  It's change over generations, caused by environmental stresses, usually.  And social support in society more or less short circuits that, since the weak don't die off, and the strong don't have more offspring.  Humans of today are generally physically larger than those of 100 years ago, but that's not evolution, our genes haven't changed, that's just due to better nutrition in childhood allowing for more complete growth.  We also live much longer, but that's due to better nutrition, medical care, etc.  In countries with terrible economies, disease, hard working conditions, human size and mortality isn't any different than it was one hundred years ago.

Also arguments about whether there's still going to be human evolution or not are generally quite short sighted.  Humans have changed an incredible amount over the last 50,000 years.  Especially compared to other animals.  Since the time of the dinosaurs, 150 million years or more, sharks (and many other types of fish) have been basically the same as they are now, since the oceans are much less changing than the land, and they are perfectly-adapted to their environment now.

So has human evolution come to a stop?  It seems like a yes, at a glance, since we've totally circumvented natural selection with technology, and our mating and breeding patterns are so anti-evolutionary on top of that.  However I (and the authors of that article linked to at the top of the page) are concentrating almost entirely on western civilization, and in any event, our window of observation is so short. Humans have long generations and far fewer offspring than most other species, which leads to fewer evolutionary mutations, and when there are such changes, they take a very long time to spread widely.  If someone in Germany had a baby boy tomorrow with a mutation in his genes that allowed him to eat spoiled food with no ill effects, digesting bacteria effortlessly, and it was a dominant trait, one that would be passed on 100% of the time in his offspring, how long would it take before his genes passed on to the entire human race?  This is assuming the passing on occurs only naturally; and not from scientific aid.

I don't have any answer how long it would take, but certainly it would be hundreds of generations/thousands of years. If he didn't have offspring of his own, it wouldn't spread at all, if his kid(s) didn't have offspring it would die with them, etc.  It's a very beneficial adaptation, and 500 years ago it would be a huge benefit, and would spread quickly, since the man and his offspring would have a great survival advantage over other people.  Since today we don't have to worry about living while eating rotten food, and if we do eat some we can usually get medical treatment, it's not even that helpful of an adaptation.  (Which is why we're debating whether evolution has stopped or not.)

Also, our genetics are such a small portion of our adult package.  Animals don't learn much, (for the most part) they don't gain culture, they are just instinctual machines, perhaps learning some better techniques for catching prey, or avoiding predators, but nothing like the life time learning curve that humans go through. You could clone the same animal 10x and all 10 of them would likely grow up to have virtually identical lives and experiences, and the most successful of them would have the most offspring. If you did the same with a human, the 10 of them (assuming for this example they weren't living together and aware of each other) would probably grow up to live very different lives, with some much more successful than the others, but their "success" in life, which we generally measure in financial aspects, doesn't necessarily correlate to their "success" in passing on their genes.  As discussed above, one of the 10 could be a garbage man and have 3 wives and 9 kids over his life, while 3 others could become college professors and have 1 kid between them.

Basically the whole topic is very interesting, but almost impossible to quantify or even qualify, to get a definitive answer.  Check back in 2000 years and see how people are, compared to how they are now?

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