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[LegoLord]

The offspring should still be sterile.  And you said it yourself:Normally such pairings are impossible.  This means that the Geep is an exception.  It's not entirely chromosomes, mind.  There are plants with chromosome numbers close or equal to several animals.  But animals and plants don't breed.

It's down to compatibility of the genes, not the number.

[MuonDecay]

The sun will last 10 billion years

well, you bolster that with another tinier sun! - Jupiter.
You might squeek 11 billion years or so. However I doubt we will be a similiar form in 10 billion years.

Humans have stopped evolving.  We'll look the same.

I had to tell myself not to nitpick two times before but I eventually gave in D:

Evolution never stops. For any species. Ever. Mutations are occurring as we speak, redheads are on the decline, etc.

[Footkerchief]

redheads are on the decline, etc.

I believe that part's an urban legend.

[Balathustrius]

Evolution never stops. ...redheads are on the decline, etc.

I hope you're not implying that redheads are unevolved.   

 

[Footkerchief]

Scientists really need to figure out how to link redheadedness to the X chromosome such that we can have scads of redhead women without all the goofy looking redhead guys.

[Muno syoan]

Redheads are repositories of two recessive alleles. If a person has a single dominant allele (e.g. light brown), red will not appear. As the gene pool homogenyzes, they become statistically less likely to crop up (this is an oversimplification).
From a biological perspective, evolution is not advancement. It means a change during transcription of DNA. Sometimes (very infrequently) these produces a trait which increases an organisms' capacity to survive. Usually, it kills them. Handily, life has had a long time to get it right.

[Baughn]

Evolution also optimizes only for what actually causes more offspring, not for what is an "improvement" in our terms. For example...

Right now, the ideal human would probably have a lot lower brain mass (brain's really expensive, guys), appear to function more or less normally, but want to donate massive amounts of sperm to sperm banks. And then die at the age of thirty or so.

Would that be an improvement? Evolution'd think so, if evolution could think.

[Belteshazzar]

At this point children would have to be manufactured instead of born to those who had severe or uncommon alterations. Now I doubt that baseline humanity would disappear assuming they weren't killed or or forced to ascend/integrate (the opinions of certain transhumanists on this matter frankly worry me at times.)

Also... yes we do need more good looking redheads, for greater genetic diversity! and stuff. I also suspect that natural blonds no longer have a selective edge due to preponderance of 'bottle blonds'. Hmm I wonder if japan will lead the way by just inventing blue haired people, along with catfolk, and robots.

[LegoLord]

The sun will last 10 billion years

well, you bolster that with another tinier sun! - Jupiter.
You might squeek 11 billion years or so. However I doubt we will be a similiar form in 10 billion years.

Humans have stopped evolving.  We'll look the same.

I had to tell myself not to nitpick two times before but I eventually gave in D:

Evolution never stops. For any species. Ever. Mutations are occurring as we speak, redheads are on the decline, etc.

No, it does.  Our genes, at this point, are irrelevant to our survival.  Evolution is not something that happens automatically; for a change to occur, there has to be a need for the change, and then the mutation happens.  Are these mutations of which you speak particularly benificial to survival?  Most likely not.  Most mutations have absolutely no effect whatsoever, normally occuring in only one cell of an already developed body and the cell is rejected.

[Kardos]

LegoLord, can you please start providing links to prove your theories?  Or to at least support them.  Because most everything you say sounds like self biased opinion.  As in, you don't believe something can work this way, so you suddenly sprout a bunch of true or false facts to support your opinion. 
I wouldn't go so far as to say human evolution has stopped.  With the advent of hyper communication, there's no telling what effect it will have on the neural aspects of our bodies.  And other physical mutations still occur in society today.  Albeit, many of these mutations occur due to human pollution.  However, the cause is fairly irrelevant.  Just because something changed one way as apposed to another doesn't mean the change is irrelevant to evolution.  Keep in mind though, mutations are a short term classification, evolution is a hindsight classification.  Meaning its fairly impossible to say evolution in humans has stopped, unless of course you've been 4 thousand years into the future to tell us otherwise, and another four thousand beyond that to reconfirm your position. 

EditEdit: http://en.wikipedia.org/wiki/Human_evolution  This here.  The evolution of the human species began about 2 million years ago.  The evolution of the Homo Sapien species began about 45,000 years ago.  The average existence of each preceding humanoid species before evolving or dieing out is about 400,000 years.  So to say that human evolution has stopped with only 15% of our potential evolutionary time frame over puts you in the same boat as every other human centric fanatic, be it dictator spouting purity of the races or a religious man stating god, whichever god it may be, created us in his/her/its image.

[LegoLord]

Everything I say is stuff from Eyewitness: Evolution, my Honors/IB Biology class, and some history courses.  And no, we aren't evolving.  Whether someone survives to reproduce is dependent almost entirely on modern medicine.  The Black Plague would have little impact on modern society; If you aren't immune, we'd soon have a way to treat it with antibiotics (I think we actually do).  Sure, there is evidence of there still being change, but whether or not it survives to the next generation does not depend on what the gene does; it depends almost entirely on human preferences.  So these changes in human genetics are completely random.  You don't evolve that way.  It's like Pure Science - research done entirely for the purpose of collecting knowledge, without any focused purpose.  We don't get what we need from it; most major discoveries from it were luck.  The genes we have now are sufficient to get us modern technology that helps us survive, just as modern needs focus research into things we need rather than getting a lot of random things that may or may not help.

Basically, evolution has gotten us as far as it needs to get us; what happens now is the "pure science" of evolution, which gets us nowhere given how long a process evolution takes.

[Zironic]

Scientists have proven average brain mass has increased over the years. Which is bad and good is many ways mysterious.

[numerobis]

Evolution is not something that happens automatically; for a change to occur, there has to be a need for the change, and then the mutation happens.

Evolution is something that happens automatically.  The mutations and recombinations happen, the former because accidents happen during mitosis, the latter because sex is fun.  Most of them end up killing us from cancer, making us miscarry, and the such.  But some stick around.

The effects on reproductive success are pretty slight due to modern medicine where modern medicine is widely available -- almost everybody in Europe, all but the poor in the US, and a handful of people in Zimbabwe.  That still leaves a lot of people who have health care not much more advanced than what we had 100 years ago.  Plus, even in the rich areas, there's diseases, allergies, and so on that can kill you.  There's mate selection.  There's genetic screening (if you know your children have a 25% chance of being born with a terrible genetic disease, you might decide not to have a kid, and instead adopt).

[Squirrelloid]

Humans are most definitely continuing to evolve.

Consider the pre-requisites for natural selection:
1) Not all offspring which are born survive (check!)
2) There is variation amongst offspring (check!)
3) Differences between offspring lead to differential survival (check!)
4) Differences between offspring are inheritable (check!)

The only one of those that might possibly need convincing is Variation -> differential survival.  For the sake of not meticulously researching this, consider the Darwin Awards.  Is it any wonder why brain size is increasing?  People still kill themselves off doing stupid things.  (See also suicide religious cults, etc...).

The number of things that are heritable is absolutely crazy, and generally not politically correct to talk about too loudly.  For example, *political party* is ~80% heritable.  That's crazy heritable - more so than height (which we know has genetic factors).  The logical conclusion is that behavior is partially predicated by genetic programming, which, while it interacts with environment, still plays a strong role in determining a lot of our attitudes.  Now, I'm not saying there is a gene for political party, or even multiple genes, but that there are behavioral genes which encourage attitudes that bias our likelihood of believing one ideology or another.  All of behavior is very relevant for a social organism, and as social change has been dramatic over even the last 200 years, I cannot believe evolution has stopped for us.

As such, its unsurprising that there are now a number of studies which document identical twins raised separately compared to another child each is raised with.  The identical twins are more similar in behavior despite being raised apart than the other child they are raised with.  Genetics apparently trumps environment enough times to be significantly noticeable and repeatable.

Basically, all the PC crap that behavior is 100% environment is wrong, it has to be wrong - we don't evolve large brains and the capacity for speech (a purely social innovation) without selective pressure to do so.  I highly recommend Steven Pinker's The Blank Slate: The modern denial of human nature for a not too out of date review and discussion of the primary literature on the subject of human behavior and its inheritance in an accessible style.  He concludes that a surprising 50-70% of behavior is genetic.  And since behavior most certainly has survival implications (ask any insurance company), i refer you to the pre-requisites for natural selection.

But that's not all.  Evolution is defined as the change in gene frequencies over time.  Consider change in frequency of something as simple as hair color or melanin content.  White americans have significantly fewer children than members of other racial groups in the US (notably latinos).  As race/skin color is most certainly genetic, that is evolution in action.  I believe that relationship holds internationally as well, both globally and in any country you care to mention.  (Ultimately, it may be because white people tend to be richer, and richer people have fewer children).

Yes, that means that winning the economy game means 'dominant' whites are losing the evolutionary game.  Oops.  (Evolutionary biologists, on average, also tend to not have many children.  Talk about not practicing what you preach!)

Basically, there's no way a population ever stops evolving.  Its simply not possible.  But for humans most of the interesting evolution is going on 'upstairs'.

[MuonDecay]

E.O. Wilson was horribly, brutally excoriated for suggesting those kinds of things. People accused him of giving fodder to eugenicists. In truth he had no idea his suggestions would spark such a debacle. He was merely reporting on findings he had found doing relatively isolated research.

He also suggested that in some ways humanity can be called a superorganism, if I remember right.