There are weeds that gradually came to resemble the crop they infested. When they were recognizably different from the crop species, people pulled them up or separated out their seeds – automatically selecting for weeds that loo0ked more and more like the original crop. Some of the traits acquired are those we actually desire in a crop plant, such as larger seeds that don’t drop off spontaneously – and so in some cases, a weed became a new crop.
Rye probably started out a a weed in wheat and barley fields. It was originally a perennial, but that didn’t work very well in cultivated fields, so it evolved into an annual, like wheat and barley. It was hardier than wheat, and tolerated poorer soils, so it eventually became the main crop east of the Rhine and north of Hungary.
Oats has a similar origin: it does best in areas with cool, wet summers, like Scotland.
It seems to me that there may be some social parallels: bandits turning into governments, alchemists into chemists, Galenic doctors into almost-scientific medicine.
West Hunter 
Mancur Olson’s Stationary Bandits:
http://www.jstor.org/stable/2938736
Maybe Christianity. Originally a tiny Jewish cult, its leader executed for insurrection by the local Roman procurator, it eventually became the new, official civic religion of the Empire. We can see the weeding process, in the sidelining of the Gnostic Gospels and the excommunication of heretics like Marcion of Sinope and Pelagius.
If rye hides out in a field of wheat until it has become so frequent that it can assert it’s own identity, that means that the rye was a natural variant and that the wheat was a established domesticated crop. So the analogy with chemists and alchemists is inapt. That would imply that the existing crop would be real chemists and that the intruder would be a ‘natural’ alchemist.
The story about rye and wheat ‘explains’ how rye comes to be domesticated by assuming that wheat already has been. But in the alchemist-chemist example presumably you want to know where the real chemists have come from not an occasional alchemist.
The same objection holds for bandits and government. If a bandit can impersonate a government that’s one thing, but it doesn’t explain where all those governments came from.
Alchemy was not all that unscientific originally. We know today that lead cannot be converted into gold because both are elements. But substances in nature don’t come labeled “element”, “compound” or “mixture”. Thus water was believed to be an element but turned out to be a compound. Air was believed to be an element but turned out to be a mixture. The conversion of lead into gold is phenomenally no more remarkable than say the conversion of sodium and chlorine into salt. So the interest of someone like Newton in alchemical research wasn’t at the time that unscientific.
To be sure there was some mystical strain in some of the alchemical tradition but a lot of alchemy was just empirical chemical research conducted without any good theoretical understanding.
Over time a lot of empirical facts about chemical transformations were learned. Alchemy gradually evolved into chemistry.
Green Gold – Blackadder – BBC
This is more likely to be a path followed by infectious microbes, now that we have antibiotics to attack the ones that standout. Virulent pathogens get suppressed, chronic pathogens that look like human cells or organelles are ignored. So they cause a different pattern of disease … more cancer, less diarrhea or pneumonia.
Man, that’s horrifying. Morbidity uber alles. I had a short story idea the other day about a chemical scientist for a deodorant company discovering that people don’t ever actually wash their armpits. The idea being that the bacteria in the armpits lead us to believe we have washed, our brain tells us it happened, but video shows nothing. I wasn’t sure where to take it though. Might be fun.
Rock into actual music. http://en.wikipedia.org/wiki/Symphonic_Music_of_Yes
It could be worse. Just think about symphonic hip-hop…
The future of classical music (according to Futurama) is already here.
LOL! Der Untergang des Abendlandes!
By the way, there’s no diversity (I mean, “good” diversity) among the seated people…
Other than size and scale, I don’t see any meaningful difference between bandits and government.
Mobile bandits have an incentive to skin the sheep. Stationary bandits have incentive to feed and shear the sheep. Otherwise yeah, basically continuous.
Poa annua (annual meadow grass) is a major weed problem in many golf course putting greens, except at the golf courses like Pebble Beach where the greens are all poa annua.
Bermuda Grass is a weed, unless your lawn is entirely Bermuda Grass. Which makes a pretty good lawn, especially if you have kids – built-in cushioning.
Turkey Red wheat was brought to Kansas in the 1870s by Mennonites from the Ukraine. Because Turkey Red has an extensive root system it can tolerate poor soils and swiftly it became the primary wheat variety planted throughout the Central Plains.
Turkey Red was replaced in the mid-1940′s by higher-yielding cultivars derived from crossing with a dwarf wheat from Japan. Hybrids can only grow with fertilizer and to around only two feet tall. Because of the short height, hybrids don’t shade out weeds, so farmers need to apply herbicides as well as fertiliser. (and because of genetic homogeneity, pesticides and fungicides too).
Turkey Red is much taller, thereby shading out weeds.
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off on a tangent – Rich Hall (who may be unpopular in US, I have no idea) does sort of off-beat anthro progs about the US. What struck me looking at photos, from the dust-bowl exodus to California, were the strong cheekbones and symmetrical faces – were they the descendants of the bringers of Turkey Red?
The Mennonites were not Ukrainian at all, they were Germans who had remained very endogamous.
What about one human population that finds itself surrounded by another, e.g. Neanderthals and ‘moderns’ in Europe 40,000 years ago.
A developing example is likely the Palmer Amaranth. It is edible and highly nutritious. It is extremely agressive, drought resistant, fast growing, produces huge amounts of seed, and has developed natural resistance to glyphosate (roundup). We have little choice but to start breeding it as a crop. It already dominates soybean and cotton fields on several continents.
Interesting. I just spent an hour looking at this invasive weed that has made its way from the south to Indiana. Nowhere did the USDA site say that it was edible and nutritious.
Wikipedia does
The leaves, stems and seeds of Palmer amaranth, like those of other amaranths, are edible and highly nutritious
So, after another few centuries of human cultivation in the sense of compulsory state education the remaining wild human variants will have been weeded out, and the cultivated persons will no longer be able to distinguish between governments and bandits?
Rye probably started out a a weed in wheat and barley fields. It was originally a perennial, but that didn’t work very well in cultivated fields, so it evolved into an annual
Interesting. Has anyone tried to breed or genetically modify rye back into a perennial?