Genetic drift causes evolution. Genetic drift itself is often caused by the need to survive in the given environment, that is, adaptive evolution, and at other times genetic drift comes about through change and spontaneous mutation. Humans must still be undergoing evolution, where evolution can be defined as "genetic drift."

A healthy child is ideally produced from two genomes, one from each parent, different enough so that there is little error when the two sets of chromosomes combine into a zygote. However, even with the over six billion people currently inhabiting the earth, reproduction through unique genomes is becoming more uncommon because of intermarriage.—That is, exogenous marriage is bringing peoples together into just one generic people. The human race is essentially becoming one giant family, where all intercourse is really incest, the result of which is genetic mutation. This problem cannot even be solved by each people keeping to itself, because even what little genetic variation there is within the system is wiped-clean by intermarriage, resulting in genetic drift within the separated communities, so instead of the human race evolving all together, hypothetically there would be several different species, all traced back to the h o m o sapiens. Of course, all this would take a long time, so it's likely there would be technology developed to ameliorate the problem of convergent genome structures. As Cerebral Stasis said, the question of ethics comes in insofar as genetic engineering and whatnot, because genetic engineering is very scary business.

Let's say that perhaps six million years go by, and still the human race hasn't degenerated into one giant inbred mob. This means that there was genetic mutation going on during those elapsed ten thousand years, because the genomes still remained different enough that reproduction could go on without really being incest.

Humans are the product of many, many years of evolution, and they still evolve even now; it's just so slow it's nearly unnoticeable. As someone brought up, the human physical structure hasn't really changed since h o m o erectus, the first upright man (though there has been change in other facets of the physical condition, such as size), but this change is relatively recent. The next major change may not be due for a long time. One noticeable genetic change happening even now is size. Many of my peers (being around sixteen or seventeen) are all around 185 cm (~6 ft), but our parents and grandparents and great-grandparents, loss of bone mass aside, are significantly shorter. Even taking into account the drugs dumped into the milk, enriched foods, and healthier diets, the height discrepancy is great enough to be attributed to the very genes of the offspring.

 

 

 

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The height difference you are noticing between your parents or grandparents is definately NOT "genetic drift" or evolution. You think that could happen in 2 generations? Highly unlikely. It is more likely that those "minor changes" you mention are things like tolerances to certain diseases or chemicals that we've produced. This is the extent of our "evolution" since homoerectus.

The height/size difference you are talking about is simply a result of people having DIFFERENT lives. There are a few schools of thought around this.

1. People, in the last 10-20 years have consumed more an more "growth chemicals/hormones" through our food supply. Those "special" grains or feeds that are given to cows and chickens to produce bigger chicken breasts. This could filter down to the people who eat that meat. For example, there was a study that showed girls hit puberty earlier when exposed to growth hormones from beef.

2. People are eating healthier and standard of living is improving. Getting the proper vitamins and minerals and eating balanced diets. The other side of it is also people eating bigger portions... generating a fat population.

 

 

 

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I disagree completely... and I'm surely not the only one...
Why do people believe in evolution? Now there's a real question... Is it because three or four guys a few hundred years ago thought it up?
Perhaps, Perhaps not.

In reality, evolution is just an idea of what "might" have happened. It has not been proven and will likely never be proven... just like the theory of creation...

people can believe what they want to believe and that's great, but they shouldn't try to force their beliefs on others as fact...

but anyway...

I have to agree that there is indeed "de-volution." People are getting dumber and dumber... I think we peaked in the 18 or 1900s...
Thanks for that bit of truth...
nice theories about evolution...

and I also agree with what was said in response to the height change discussion... interesting stuff...

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Of course, GH and other hormones ample in the food and milk supply in many industrialised countries has a lot to do with the height discrepancy between generations. Here's an example, however, how height was affected in the opposite direction through genetic drift. The Pygmy people are famous for their tendency towards a smaller size. This size is surely not accounted for because they don't drink the same milk or eat the same foods as perhaps you or I would eat or drink; rather, the size difference is accounted for because their island is very small and therefore it has only capacity enough to support a small system of life. Rather than few people living on the island, their bodies adapted over time to become shorter. The smaller size enables them to consume less food and resources of the island to survive.

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Human will involve into mutants with special supa human ability... just like the x-men ... nah... just jk..

This may sound stupid, wat most of my fren thinks that human may eventually evolve to monkeys....

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This discussion is biased towards *person* sapiens as the superior species.
When considering evolutionary theory, if you qualify a succesful race to be:
A succesful race that can reproduce the most (and most viable) offspring
then my money is with bacteria

First of all, thanks for bringing up such an interesting topic.
Sorry, but how is *person* sapiens the correct terminology for humans?
Some anthropologists call us h_o_m_o sapiens (both modern humans and anatomically modern humans - our immediate predecessor), while others assert that we modern humans are h_o_m_o sapiens sapiens.

I like your point. Our technology plays a major role in what defines us. A popular theory is that we basically overran any competition hundreds of thousands of years ago with the distinct advantage of better tools and use of fire, among other things. A side note: One of Michael Crichton's books (I think it was "Prey") points out that if we homogenize all our global cultural and intellectual facets then we doom ourselves, because it is diversity which protects us as a species. This danger leveraged with technology (eg the internet). It's an interesting read.

I think it's important to remember that evolutionary theory is based on struggle. That is how the representatives of genetic drift (thanks for pointing out the term, morosophos) are "selected" to survive and pass on their genes to the next generation, but only if they meet the requirements to survive. WIth technology to help us survive many environmental challenges, then this drift will not be quite so hindered.

But there are many ways to die (as a race), and mother nature can be a very real threat. But this doesnt really apply to the current thread - I mean how can people evolve and be "selected" to survive a massive meteor collision?

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first off, this is for everyone who said that evolution is a theory... and of course it is.... but hence he put Theory 1, 2 and 3 not fact 1, 2, and 3...

@jhsmurray The filter on the forums blocks the word H*O*M*O but that is what they meant.


Now to the subject,

Although evolution is a theory and is being worked on the become facts. I totally believe in it. I an agonistic, which basically means that i am kind of iffy about the existence of god, but in my terms even more so the fact that he does not have all of this great power to create earth and life, and emotions.

And i have not ever head of thinking such as your


thats not the exact quote but close enough

I have never heard of that and i think that it will never happen. But i could be wrong, i think that humans maybe some day will evolve into somthing greater than humans, maybe aliens, and we will leave this planet and let the normal humans start themselves over again then the theory's of aliens wont be an theory it'll be a fact muhahaha -joking-

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isnt theory one and three the same? but i think that we will evolve into something super-human, or super-natural, whichever. We are supernatural to apes so what we evolve into will be super-natural (human) to what we presently are. What causes evolution? is it just one mutation on someone who has babies, who has babies, and so on and so forth? cause that would take millions of years, so who knows? there may not even be another big change before we are all killed. well thats a theory. have fun with this topic everyone

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Now, all of you who comented evolution bring *person* sapiens as the only one who can evolve. All you thought of is evolution of yourself or how can you be stronger, faster, smarter.
Well i think that is not the point of evolution. I think that evolution is process that lasts from the begining of the universe. All of nature as it egzists now in our minds is what "evolved" from big bang.

So what do you think the next step is?

I think that we should divide our evolution in two ways.

1. Evolution that we can be part of. To be more precise, it is combining all of our knowlege into making US more powerfull (whatever it would me from mechanical implants, to Matrix enviroment)

2. Evolution that we dont want to be part of. End of the world!!! Who wants to be here when it happens? Nobody. Even the Pope it self would split if he would have a chance.

Both of these will happen sooner or later, and the point is not to be "afraid" of any version of events. When the time comes we will be ready.

Evolution is deeply connected to survival. From nature who wants to survive our exploatation, from us who want to survive in nature.

We are all tested on evolution every day and we don't even realize that.
Some samples:
1. How can we encounter an alien race when we hate each other beacouse of the color of our skin?
2. Imagine that Aliens really come here and that they are all gay that would be awsome...

Evolution is nothing more than giving the best from your self every day!!!

P.S.
And now my hosting is going to evolve a bit

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i think you may be correct in that we could devolve. I would hope that we are going to evolve a few more times. I dont know how but i would like to believe we will. Reality steps in though and i see us blowing the hell out of eachother in some war or something senseless because we cannot treat each other with respect. There will always be one idiot out there who is hellbent on taking over the world or someone who cannot just settle for what they have and want more. We are destroying the world and we all know it since we see the ice caps melting and we even know what is causing it. But are we truly doing anything about it? No! Until we actually stop using oil and go to something that is plentyfull and easy to produce we will continue killing ourselves. But nobody is taking any real action to stop it. I find it hard to believe that the United States and other countries with all it technological prowess cannot put in place an alternative to todays oil. I used to drive a car that got 58 miles a gallon. That car is now off the market and youd be lucky to find one that gets anything close to it now. Thats truly sad.

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