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Permalink Reply by Heather Spoonheim on February 9, 2012 at 1:01am

Trisomy is an example of genetic information being expanded.  When one has 3 of a particular chromosome rather tan 2, they have a 50% increase of information at that juncture.  Trisomy is not always deleterious, and therefore can be passed along.  Look up XYY syndrome, argument from ignorance refuted, irrefutably.

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Permalink Reply by archaeopteryx on February 9, 2012 at 10:29am

Stuart - As we know, evolution occurs via miniscule genetic mutations that either add to an organism's survival rate, or do not. When they do not, the altered organism usually doesn't live long enough to pass on his mutation. When the mutation is advantageous, the mutation is more likely to be passed on. This process takes place over millions of years, and we know it as natural selection.

BUT, there's also artificial selection, that takes place far more quickly, quickly enough that we can actually see the results. The most perfect example would be that of the evolution of a timber wolf 13-15,000 years ago, into today's tea-cup chihuahua, orchestrated, not by Nature (or "god"), but by Man. Nature works the same way, it just takes longer.

See what your creationist has to say about that.

pax vobiscum,
archaeopteryx
www.in-His-own-image.com

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Permalink Reply by Nelson on February 9, 2012 at 12:16pm

I'm afraid I have to reply to this simply so that people don't read your post and become misinformed.

1. Evolution occurs via miniscule genetic mutations...

Well, evolution occurs in many ways. There's natural selection, sexual selection, genetic drift. Furthermore, not all natural selection is the responsibility of mutations. There's also errors in recombination.

2. ...that either add to an organism's survival rate, or do not.

Except most mutations are actually neutral, they neither add to or detract from an organism's survival rate. (Note that regarding the set of significant mutations, most are harmful.)

3. When they do not, the altered organism usually doesn't live long enough to pass on his mutation.

This just isn't true. Natural selection is a differential statistical process, not a zero sum process. Once that's understood it should become clear that harmful mutations may persist in a population for many, many years. The key thing is that "harmful" mutations reduce an organism's reproductive fitness. Yes, some mutations are so harmful that they don't even allow an organism to survive to sexual maturity or to mate once they become sexually mature so that the harmful mutation can't be passed on. But most "harmful" mutations are only harmful in the sense of not being beneficial or neutral, in the sense of not lending themselves to the organism's reproductive fitness in the way that a beneficial mutation would. It's about being not as good, not about being incompatible with the survival of the organism or even to the population of the organism possessing the mutation.

4. When the mutation is advantageous, the mutation is more likely to be passed on. This process takes place over millions of years, and we know it as natural selection.

Again, this just isn't true. Much evolution takes place over short timescales and is quite detectable and noticeable within a human lifetime, often within a scientist's doctoral program. There is no end to the examples of this.

5. BUT, there's also artificial selection, that takes place far more quickly, quickly enough that we can actually see the results. The most perfect example would be that of the evolution of a timber wolf 13-15,000 years ago

Obviously, in light of the correction in point 4, this is inaccurate as well since, as explained, evolution is quite detectable over short timescales. But I just wanted to comment on the dating of the domestication of the dog. The latest fossils have pushed those dates back to double what you quote. We've found a 26,000 year old dog fossil and, just recently, the fossil skull of a wolf-dog showing obvious signs of domestication dating to 33,000 years ago.

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Permalink Reply by archaeopteryx on February 9, 2012 at 12:51pm

Well, at least I spelled my name right - or did I?

pax vobiscum,
archaeopteryx
www.in-His-own-image.com

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Permalink Reply by B Davis on February 9, 2012 at 6:17pm

Acting as if humanity could witness evolution happening right in front of their eyes is nuts.  First and foremost, evolution is defined as the variation of allelic(gene trait) frequencies in a population over time, not a singular organism.  What people tend to forget, or actually never learn or comprehend, is that evolution has no end goal, no plan, no desire to be better than the prior generation.  Because of this specific reason, it would be an impossibility to act as if one could observe some visible mutation as a direct result of evolution.  Natural selection does not choose the best genetic traits for a population, instead it chooses good enough for whatever function being performed.  However, if you choose to do some research, look up horizontal gene transfers in bacteria.  There are quite a few examples of punctuated equilibrium and what can cause the pace of evolution to vary.  Remember people, Earth is roughly 4.6 billion years old, evolution is literally in NO HURRY!

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Permalink Reply by Dave G on February 9, 2012 at 6:30pm

Actually, we can observe evolution in a human lifetime. Maybe not measured in minutes and seccnds, but definitely measured in years and decades. A perfect example is the bacteria that evolved to metabolize citrates. It took a couple decades to happoen, but it was observed, recorded and tracked. They even kept samples of different generations over the years which allowed them to go back and roughly place when the various mutations necessary first appeared.

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