Quote from: CoinCube on September 26, 2016, 04:01:55 PM

Quote from: qwik2learn on September 26, 2016, 06:52:43 AM

they somehow had to ensure that their vision would be carried forward through countless generations that had to remain committed to planting, harvesting, culling and crossbreeding wild plants that put no food on their tables...
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Nearly all domesticated plants are believed to have appeared between 10,000 and 5,000 years ago, yet in the past 5,000 years, no plants have been domesticated that are nearly as valuable as the dozens that were "created" by the earliest farmers all around the world.
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As they grew, their seeds and grains became large enough to be easily seen and picked up and manipulated by human fingers. Simultaneously...

To domesticate a wild grass like rye or any wild grain or cereal (which was done time and again by our Neolithic forebears), two imposing hurdles must be cleared. These are the problems of "rachises" and "glumes"...

That adjustment was of extremely daunting complexity, perhaps more complex than the transformational process itself...

However it was done, it wasn't by crossbreeding...

The argument above seems to assume that a massive change in wild plants is required before they could provide any degree of nutrition to early man. However, is this really the case? The source below argues that even the wild ancestors of modern crops were eaten extensively by early man despite the difficulty in preparing them. If this is correct the wild grasses and grains did "put food on the table" just not nearly as much as their current domesticated descendants.

http://www.naturalhub.com/natural_food_guide_grains_beans_seeds.htm

Quote from: naturalhub.com

The human animal evolved to eat every animal or plant that wasn't actually toxic (and, after simple treatments, some that to greater or lesser degree were). Seeds are a rich store of energy, some have good protein levels, vitamins (especially vitamin E), minerals, and protective phytochemicals. Living as wild animals for the last million years or so, we ate every seed that was worth collecting, grass seed, legume (bean-like, pea -like, peanut and others), and any other seeds that were sustaining and productive, or big enough to be worth bothering with.
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No reasonable energy source was ignored, and wild seeds were no exception. Indeed, grindstones with adherent plant starch from before 160,000 years ago - when the first recognisably modern humans appear in the fossil record - may have been used to grind grass seeds [ref]. We, of course, ate every non-toxic seed (including tree seeds) present in the environment we had moved into. There are many plants with edible seeds in the various climatic zones of Africa, but relatively few have big enough seeds, or are productive enough, to be worth expending the energy which are nicer to eat, easier to store, and require no preparation.

Accessing the Nutrients in seeds

While grubs, meat, tubers, fish and plant foliage can be eaten raw, all these things are physically easier to eat cooked, or cause intestinal disturbance if they are not cooked. Seeds are no different.
While you 'could' eat whole rice grass seeds (for example) without parching them first, only about 25% of the proteins are able to be digested. Cook the whole seed, and about 65% of the protein is available. Grinding raw rice seeds would probably make more than 25% available, but equally, grinding and cooking would likely improve protein availablity beyond 65%. The cultural evolution of both grinding and cooking seeds brought evolutionary advantage in the form of greater access to protein - at least, for those tribal groups who had the technology.

Grass seeds, in particular, had to be heat 'parched' anyway, to get rid of the adherent woody 'chaff' covering the seed (later, with domestication, this chaff became easy to remove by beating). So a degree of 'cooking' was more necessary than a choice.

A few seeds have somewhat less protein digestability after cooking, but they are the exception. You would have to cook grass seeds at 200-280°C (392-536°F) to reduce rather than improve, their protein digestibility. Meat protein digestibility, in comparison, decreases when cooking is above only 100°C (212°F).

Seeds contain 'antinutrients' - substances such as saponins, tannins, 'protein splitting enzymes' inhibitors, and phytates. These compounds reduce the body's ability to access the nutrients in seeds. The type, and amount of anti-nutrient varies both with the species of plant, and with the local variety of the species (common beans, Phaseolus vulgaris, for example, have a wide range of phytic acid and tannin concentrations - with white seeded beans having least tannins-depending on the variety). Some have several different anti-nutrients, some have few, some have relatively a 'lot' of any one anti-nutrient, some have very little.

Most, but not all, antinutrients are destroyed or reduced by cooking. Soaking and leaching are necessary to reduce some antinutrients, particulalry in some varieties of bean and other legumes. Soaking and sprouting seeds also reduces phytates. Soybeans, for example, contain a contain a 'tryptophane inhibiter' that interferes with the absorbtion of the amino acid 'tryptophane'. The inhibitor can be neutralized both by cooking and by sprouting (the sprouted root must be 3 to 4 inches long for this to be largely complete).

A very low percentage of the starches in some seeds 'resist' being digested ( up to 7% for wheat, and oats and 20% for baked beans) These undigested starches are fermented by the microflora of the colon, producing variable quantities of gas.

Guided by the practices of recent African gatherer-hunters, it seems likely our African ancestors mainly dealt with anti-nutritional factors by roasting the seeds. Sometimes they were soaked as well, either before or after roasting (and grinding). These are classic techniques that we use even today when preparing legumes; although westerners rarely roast any other than peanut seeds, and occasionally soya seeds.
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In parts of Australia, the aboriginal people regularly harvested wild grass seeds (chiefly a wild 'millet', Panicum spp.), and it is likely that given time, they would have domesticated them. Indigenous tribespeople of the grasslands of Southern South America gathered grass seeds for food, and even brought one species of brome grass into cultivation. In Mexico, one of the local 'panic grasses' (Panicum spp., a kind of 'millet') was collected, and ultimately, domesticated. Palaeanthropologists have found 19,000 year old stone mortars for grinding grain show that wild grains were not just parched, but processed, from at least since that time.[ref]
Saharan wild grass harvest There is a lovely cave art picture of women gathering wild grasses in the once productive Sahara region of Africa at the Paleologos site (www.paleologos.com).

Our ancestors probably parched the whole grains on ember-heated stones (this would have burnt off the adherent husks around the seed), and made a dough from the cooked flour (Tibetan people today eat a dough from roasted barley flour mixed with tea and yak butter and formed into a ball - tsampa). Such doughs laid on hot stones or embers would have made the first unleavened 'bread' . Or the roasted flour could perhaps have been mixed with water to make a thin 'porridge'.

We should remember that our ancestors 10,000 ago were just as smart as we are today. They lacked only formal education and the history of prior discovery that we have. They would have put considerable thought into their sources of food and later their crops as this was literally a matter of life and death. I agree that the process of converting wild plants into domesticated crops is dauntingly complex requiring drastic and multiple genetic changes. I am not yet convinced that it could not have been achieved by sustained and selective breeding over a 5,000 year window.

There is likewise no arguing the fact that nearly all modern domesticated plants appeared between 10,000 and 5,000 years ago and since then there have been few new staple crops. However, this could also be explained by the fact that perhaps it takes two to three thousand years of dedicated and selective breeding to achieve the large changes that we see. Such a process may be very labor intensive requiring detailed examination of each and every plant every single generation with decisions made regarding which plants to use the following generations. It would have to be sustained over generations and this level of vigilance would only occur if existence itself depended on it. Once success was achieved with a few crops it would be inefficient to repeat the process from scratch with new plants when better results would be achieved by building on past success for the reasons outlined in my post above.

Yes changing wild plants into their current highly optimized crops required modifications of entire suites of genes. Yes it would be very difficult to accomplish even today if we tried to repeat the feet. However, the time scales involved here are vastly different. For ancient man we are talking about multiple thousands of years to achieve results. That is a very different undertaking than trying to repeat that multi thousand year process in a year or two.

I don't even think it would take that long. Every year pick the seeds from your best crop, and next year plant those, and repeat the process. The people don't have to even be aware of the fact that over time the crop will change into something very different after a couple hundreds of years. They might not even notice the subtle changes, just like we don't noticed the difference in someone we've known for many years, until we see a picture of them from back in the day.