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Farmers created the crops we know by saving seeds. Saving seeds is intrinsically as old as agriculture itself, because saving seeds was the hallmark of what made what the humans were doing to be agriculture.

Now, hybrid corn has been sold for about 90 years. Hybrid corn strains almost always out-perform their inbred parents due to hybrid vigor, so farmers have always preferred the hybrid versions once they were available. (It is interesting to note that modern inbred strains dramatically out-perform the initial hybrid strains due to the overall improvement in the genetics of corn.)

There were commercial seed producers before then, but the farmers generally didn't see much benefit from using their products. Using someone else's seeds meant a high risk of reduced production because the genetics of those other seeds was not tuned to the farmer's fields. Saving and reusing the best of their crop as seed the following year was so very easy and ensured consistent or improved production from year to year as the genetics of the crop adapted to the micro-environments of the fields.

Lately, more farmers have been making efforts to save their own seed. They're realizing it gives them more control as well as helps specialize their crops to the land they work, both aspects that were lost under the influence of the large seed vendors.

Is natural selection an algorithm that is "looking for" humans?

Nope. We are just a happy accident in the history of life.

That inheritance improves the odds slightly was not in question. The point was that there are other unaccounted forces (survival, environmental changes, luck) working against the unaccounted filtering effect, such that you cannot assume progress just because a filtering effect exists.

Given that the evidence supports the fact that this is in fact what happened, that assumption is more than justified.

Do you believe that 3.1 Gbs of human genome is filler? If true, you should be able to irradiate and randomly mutate somewhere around 99% of a human's DNA sequence with no ill effect.

See, this is where your simplified version gets you into trouble. Genes are added to genomes all the time, from gene copying mistakes to interspecies breeding to bacterial gene interchange to endogenous retroviruses. Entire chromosomes are sometimes duplicated. Random events are adding genetic material all the time, and natural selection is winnowing out the non-working combinations.

You assumed that humans evolved from chimpanzees, extrapolated that rate to the past, and found it reasonable that humans evolved from chimpanzees and fish. That's circular reasoning.

Nope. I demonstrated that, if evolutionary theory is true, the rate of change as demonstrated by our closest living relatives is consistent with the amount of time that change had to have happened, which is precisely what you are denying.

Can you support the assumed human mutation rate with a measured human mutation rate?

Sure. Start here:

The average mutation rate was estimated to be ~2.5 × 108 mutations per nucleotide site or 175 mutations per diploid genome per generation

6 million years divided by an average generation time(20 years for humans, 15 for chimpanzees, so 17.5 average for both species) gives us 342,857 generations. This yields 59,999,975 mutations.

Can we reverse engineer all those intermediate organisms? (Can't do that now, but should be possible if evolution is true!)

Can we extrapolate the likely form and location of the intermediate organisms? Sure. That's how we discovered Tiktaalik, for example. The researchers worked from an understanding of the development of the tetrapods and the population distribution in the fossil records and predicted that they would find a proto-tetrapod in Devonian strata in Canada. And they did. As for whether they can be recreated exactly, then no, and there is no reason to expect it to be possible at all. We can compare related organisms to determine which genes were likely conserved or developed independently. That can get us in the ballpark(which is why we can infer a lot about intermediate species), but recreating an entire extinct genome is likely never going to be possible.

Filters always remove information. At best, with an analog signal carrying digital encoded information, you can remove the noise without harming the information.

Hey, you are almost there! Congrats!

Filters can be a part of an overall creative process

Bingo! That's what I was saying!

A random string generator has the potential to "write" a novel.

Indeed. And I have generated the first paragraph of "Romeo & Julliette" using one that starts with a small string of random gibberish and uses random mutations and selection to generate it. Of course, the couplet is just a model used to represent a theoretical genome which is fit to survive in a particular environment.

Having solved that simpler problem, does

Heirloom stuff has lost much of its nutritional value because it's too imbred. As for what our bodies are optimized for, it's certainly nothing you can find on a farm or in a grocery store. 10,000 years of agriculture have allowed us to artificially select desirable traits in plants, which does the same thing as genetic engineering. Here is an article trying to reverse engineer the genetic modifications that took the tomato from a 1 g fruit to a 1000 g fruit.

Gene transfer happens in nature anyway, much like the experiments done by the LHC occur in the upper atmosphere routinely. That is why you cannot find the plant we modified into the tomato (or any crop), the genes from the artificial version we've cultivated have contaminated the natural version we started with, until neither resemble what a pre-agricultural human would have eaten.

i agree with you that the post above is not insightful; however, i will disagree that humans have a higher mutation rate than e.coli. humans have much more accurate error correction machinery than bacteria.

http://www.genetics.org/cgi/content/full/156/1/297

however, the previous post is not insightful for a multitude of reasons. the crucial error is that the anonymous coward is not taking into account various evolutionary forces. the citrate mutation could have appeared and disappeared by chance (genetic drift) multiple times if the citrate metabolism gene did not confer enough of an advantage (generally it has to be s > 1/N, where s is the advantage and N is the population). so the simple arithmetic while adorable, is deeply ignorant. to edify, get this from your library...

http://www.amazon.com/Population-Genetics-John-H-Gillespie/dp/0801880084/

http://www.genetics.org/cgi/content/abstract/176/3/1759 [genetics.org]

You may also be interested in a more detailed explanation which includes some examples of beneficial mutations and not-so-beneficial mutations as well.

As to Dawkin's actual quote in the Blind Watchmaker, he repeats the usual line about how micro evolution over time can lead to macro evolution given enough time while at the same time referring to the contradiction that we find in the problem posed by the Cambrian Explosion.

Credits: I am quoting portions from www.anointed-one.net

I also happen to think that as we investigate more and more pairs of close species, we will find this is not at all an uncommon pattern. There are lots of hybrids out there in nature, and you can be sure that genes make it across "species boundaries" with some regularity for quite a while.

One final note to destroy my credibility. Is anyone surpised that people had sex with chimps? (Okay, proto-humans with proto-chimps) We are a couple of horny species. I don't know too much about chimp sexual habits, but we humans sure are a kinky bunch to boot.

She's his wife.

+3 Informative, but sadly, -3 Incorrect. Lionel Sharples Penrose, the geneticist, was Roger Penrose's father.

L.S. Penrose was Roger Penrose's father.

This is one of the really amazong stories to come out of modern genetics. There is an excellent book (for all people not just scientists) called The Seven Daughters of Eve which guides you thorugh the basics of the science. (The title despite its religious overtone is really about the 7 women that 95% of all Europeans can trace their ancestry to).

There are also technical papers (there are tons but these are good places to start) here and here (this one discusses the long unknown origins of Pacific Islanders which was one of the early successes of this technique).

This study is an incredible combination of biologic science and social science, which could has the possibility to answer questions that are not able to be answered by traditional archaelogy and anthropology. It is quite amazing to think that our ancestry has been preserved, not in rock and artifact, but in our own living bodies.