Evolution

[ydoaPs]

through all of human history we havn't seemed to evolve. is that because we are a sentient species?

[J'Dona]

Certainly humans have evolved; just look at the changes in human physical features between different areas on the planet, over only a short time since the first humans moved out of Africa. People might not be evolving toward anything particularly adapted to one area now that travel across the world is widespread, but they're still evolving. It's just not been very long.

 

I'm confused though, why would sentience necessarily stop that?

[ydoaPs]

that is just genetic varience. just different shaped eyes, different shades of the same skin pigmentation, and the placement of fat.

 

sentience would change things because we decide what we want to do. we use more than instincts.

[JaKiri]

that is just genetic varience. just different shaped eyes' date=' different shades of the same skin pigmentation, and the placement of fat.

 

sentience would change things because we decide what we want to do. we use more than instincts.[/quote']

 

Are you using some kind of bizarro definition of evolution?

[ydoaPs]

how have we evolved at all in history?

[JaKiri]

how have we evolved at all in history?

 

By changing in traits, both internal and external?

[ydoaPs]

specifically. "by changing traits" is a lame answer that doesn't say anything

[Skye]

The eyes, pgmentation and fat you mentioned previously?

[ydoaPs]

that isn't evolution, we have had those traits thoughout all of history. try again.

[Skye]

Well ok, for evolution to have occured what must happen, in your opinion?

[ydoaPs]

there has to be a change in the species

[LucidDreamer]

I would agree with yourdadonapogos that we have physically evolved very little in the course of human history. But human history spans no more than about 6,000 years, which is a very short time compared to the eons that life has been evolving on earth.

 

I would also argue that although man has not physically evolved much in the last 6000 years he has in fact evolved more than any other organism in the history of earth in that time. Before man and civilization the only way a species could pass the information that it had accumulated for millions of years about how to survive was through its genes. Since language was developed and writing was invented the amount of information that is passed down through the human species has become almost unfathomable.

 

We are no longer constrained as other organisms are to the information in the genes. We are no longer restricted to one form of existence that takes millions of years to remake. Our existence is no longer dependent upon the whims of nature. We fly higher than any bird, dive deeper than any marine animal, and run faster than any land animal. The burden of evolution has been taken off the shoulders of natural selection and placed on the beams of libraries and the infrastructure of the Internet. With a huge and ever increasing population with limitless combinations of alleles and modern medicine to ensure that most combinations survive there will be little natural physical evolution that is not orchestrated by our own hands.

[Skye]

And assuming that the races we have today didn't exist at some point in the past, doesn't that mean there's been change?

[ydoaPs]

See, i was right. It was sentience

[JaKiri]

See, i was right. It was sentience

 

No you weren't, he said precisely the opposite to you. The fact that the justification was the same is hardly supporting your cause.

 

Can you please define what exactly you would class as evolution, or changes to the species? Recent examples of evolution, for instance, would be growing immunity to certain forms of illnesses. Does this not count in your eyes? What about the other changes that have been mentioned?

[LucidDreamer]

90% of an augument is in the definitions. I'm afraid this argument will go nowhere because evolution is such a broad term. Lets start with a definition then restate the question. Lets define evolution as the change of a species to the extent that they are no longer able to procreate with the original and with a DNA change of 1%(about the same amount of difference in DNA between humans and chimpanzees). If there was no genetic engineering and no separation into isolated groups for long periods of time would man evolve into a new species in 2 million years according to this definition. Lets also pretend that his civilization grows and experiences no major disasters with no major depletions of population.

[Radical Edward]

One aspect of evolution is change in allele proportions within the population. This has definitely changed, for example the rise of sicke cell anaemia in malaryial areas of africa. note also that human history is very short, evolution takes place on much longer timescales, and is the result of selection due to the environment. the thing about humans is that we control the environment, so there is much less in the way of selection pressures on us, since we can do things on historical rather than evolutionary timescales now. One example of this is the appendix. prior to surgery and antibiotics, appendicitis was pretty much 100% lethal. this would have selected for people with different shaped/absent appendices, however surgery has removed this selection pressure.

[Radical Edward]

Lets define evolution as the change of a species to the extent that they are no longer able to procreate with the original and with a DNA change of 1%(about the same amount of difference in DNA between humans and chimpanzees).

 

what is your justification for this? are you saying that Homo sapiens are the same species as H. neanderthalis or H. erectus?

[Skye]

This thread better not be about why we haven't speciated since we last speciated.

[Sayonara]

/obligatory "This thread is stupid" comment

 

 

Plenty has changed in humans over the millenia, but to answer this - at the very least - "all of human history" needs to be defined.

[J'Dona]

Lets define evolution as the change of a species to the extent that they are no longer able to procreate with the original and with a DNA change of 1%(about the same amount of difference in DNA between humans and chimpanzees).

Interestingly enough, they think that humans and chimpanzees can procreate. It's just that nobody will, although there have been rumours: http://www.rotten.com/library/cryptozoology/humanzee/

 

If they did, then they'd produce a human-chimpanzee hybrid, thus leading to another form of evolution by introducing a new species.

[admiral_ju00]

But human history spans no more than about 6' date='000 years,

[/quote']

 

6,000 years?

 

Check your dates pls.

 

Our existence is no longer dependent upon the whims of nature.

 

You think so? Why?

 

We fly higher than any bird' date=' dive deeper than any marine animal, and run faster than any land animal.[/quote']

 

These help, but do not use them as the sole predicament of evolution and it's forces.

 

The burden of evolution has been taken off the shoulders of natural selection

 

To a degree, yes, but Natural Selection is still at play, every day and all around you.

[JaKiri]

If they did' date=' then they'd produce a human-chimpanzee hybrid, thus leading to another form of evolution by introducing a new species.[/quote']

 

Hybrids are sterile..?

[J'Dona]

Erm, yeah... I noticed that after I found the link and posted it. :/ I forgot to change the post...

[LucidDreamer]

My requirements for evolution were chosen so there would be no argument over whether that degree of change actually constituted a new species. To answer radical edward, I did not pick the amount of difference between Homo sapiens and Neanderthal man because its anyone’s guess as to whether Homo sapiens and Neanderthal man could produce viable offspring and I don’t believe we have the genetic code from them.

 

"6,000 years?

 

Check your dates pls."

 

Ok, I did. Recent evidence shows the most ancient writings to be from around 3100-3300 BC. Doesn't seem like enough to quibble about and I really don’t disagree with the rest of your post.

 

Yes the frequency of alleles has shifted some in human history. But will this fluctuation actually bring about the creation of a new species in time. If you took a man from 40,000 years ago and dressed him up in a suit and put him on wallstreet, noone would look twice.