What, if anything, happened during the Neolithic?

First published 20121020 / Last updated 20121028

Bread is one of the most typical products of agriculture, and, somehow, bread is agriculture. Like many other people, I assumed that bread is a neolithic invention. In reality, “bread” and other innovations, appeared gradually over time, and well before the Neolithic. All the necessary pre-inventions must have been available: containers to harvest seeds, fire, grinding and cooking, which, by the way, are themselves not “simple inventions”. The same applies to crop agriculture, for which a number of pre-inventions are necessary: tools, some form of soil preparation (note 1), the recognition that plants grow from seed, that seeds need water to germinate and to grow, that they need protecting and, maybe, that they grow faster near human settlements, especially near refuse and animal droppings (fertiliser). Bread predates agriculture, but it is probably the increased demand for bread and other food  that has been driving the expansion of crop agriculture, rather than the invention of agriculture permitting an unprecedented population explosion (Note 2).        

According to my my little database of inventions, the domestication (note 3) of the main cereals took place around 10000 BP (note 4)  for millet (Lu et al

One of the colorful illustrations of the paper by Zheng,  Yan, Qin and Jin (2012) showing the diversification of  American mtDNA lineages. According to the authors, the star-like pattern is typical of fast expansions, which the authors quantified, eventually reaching the conclusion that the growth took place after the last glacial maximum but before the Neolithic. The figure is given here mostly for its aesthetic side!

2009), wheat (Eckardt, 2010) and barley (Badr et al 2000, Dai et al 2012) while rice was domesticated later, around 7000 BP (Lawler 2009). The dates are, of course, indicative, but it is generally agreed (Toussaint-Samat 1997, Zohary et al 2012) that cultivated cereals appeared 9 000 to 11 000 BP in the Middle East.

An article published in 2004 in Nature by Piperno et al showed that barley, and possibly wheat, were routinely ground (note 5) at the Ohalo II site (Israel) about 12000 years before the advent of agriculture as we understand it. This would be 22000 BP, during the Palaeolithic, 9000 to 10000 years before the domestication of the main cereals during the Neolithic.  The article also mentions that a special alignment of burnt stones covered by ash suggests the presence of a hearth-like structure used as a simple oven: ten thousand years before the invention of agriculture, humans were thus baking some form of bread at Ohalo. The implication is that wild wheat seeds would be harvested, ground, maybe fermented, mixed with water and possibly a leavening agent such as yeast, and eventually spread directly onto the heated burnt stones mentioned by Piperno (Note 6). The resulting griddle cakes would have been very different from what today we know as “bread”, but we would probably have liked them!

There are good reasons for cooking cereals, as the amount of available energy increases in comparison with the raw, unprocessed grain and the food is more easily digested. It is interesting to note that the forerunner to cooking cereals (i.e. boiling with water) may have been roasting; this had the advantage of removing grain from spikelets and eliminating glumes. For cooking proper, earthenware cooking vessels were needed, but the first evidence of pots that would resist heating dates from 10 000 or 9 000 BP (Mureybet, Syria, not far from the Ohalo sites) and bread is thus older by ten centuries.

Jacob (1954) remains a classic on the history of bread. He wrote that bread is first known from ancient Egypt, and this is actually where the first proper ovens were discovered (from about 6 000 BP). Jacob stresses that barley was not very suitable for this bread, and that this is one of the reasons why barley has been worth less than wheat, starting in early times (note 7.) Jacob’s view is that during the period before “bread”, barley was used to prepare roasted flat cakes, which is indeed what we see at Ohalo. Jacob quotes Plinius’ opinion that, during most of their history, Romans used gruel, not bread (pulte non pane; note 8). Undoubtedly, this applies not only to Romans. It remains that bread did bring a change: it is durable (it can be stored over long periods of time), it is nutritious (the available energy content is greater that that of the unprocessed grain) and it is light (it can easily be carried in a bag).

Artist’s reconstruction of one of the grain storage structures described by Kujit and Finlayson (2009) in Jordan, showing upright stones supporting larger beams, with smaller wood and reeds above, and finally covered by a thick coating of mud. The suspended floor sloped at 7° and served to protect stored foods from high levels of moisture and rodents (Illustration by E. Carlson).

The most interesting observation that I derive from the paper by Piperno et al is that when humans “decided to launch the neolithic revolution”, some of the fundamental innovations that were needed for the “invention” of agriculture were already to hand.  There is bread technology, but there are others. For instance,  sophisticated grain storage structures (Kujit and Finlayson, 2009), were invented before agriculture. Cooking pots were available too, as mentioned above. Ceramics as well (note 9). It has been argued too (Craig et al 2011) that, when agriculture arrived at higher latitudes in Europe, people did not change their eating habits, i.e. outputs of agriculture seamlessly fitted into existing food habits. 

Bread was indeed a powerful justification for the invention of agriculture. But was bread a necessity? In other words, was something happening that led humans to increase the production of bread, by dramatically expanding the use of known technologies.  

Craig et al mention that farming drove rapid global demographic expansion of human populations (1), although reasons for its success are harder to decipher from archaeological evidence. This is a common opinion: thanks to agriculture (both crop and livestock production), population was able to markedly increase. Mazoyer and Roudard (1998) note that, between 10 000 and 5 000 BP, human population increased tenfold, from 5 to 50 million; between 9 500 and 9 000 BP, small villages (0.2–0.3 ha) were replaced by large villages (2–3 ha) and, in general, many changes took place in living patterns. 

The prevailing opinion seems to be that agriculture pushed population. My opinion is that it is more likely that population expansion pulled agriculture, that humans were  “forced” into the Neolithic revolution. A recent paper by Zheng et al (2012) argues that, possibly driven by favourable climatic conditions, major population expansions started after the last glacial maximum, but before the Neolithic!  In another recent paper Dietrich et al (2012) describe the huge celebrations that took place at Göbekli Tepe, which  must have placed stress on the economic production of hunter-gatherer groups. Maybe in response to the demand, new food sources and processing techniques were explored.  Experts do not agree on the function of Göbekli Tepe (cf Banning 2011), but it is certain that the structure is huge,  and the celebrations were huge too. Both the construction of the building and the coordination of the festivals required coordination, which may have been religious.

In the previous version of this post (Gommes  2004), I suggested that competition for natural resources may have become acute and that hotspots (Gommes

Range wars in a Lucky Luke comic. Source: http://www.dupuis.com/catalogue/FR/al/650/des_barbeles_sur_la_prairie.html. The French comic  was the basis for the TV series “Of barbed wire on the meadow” (http://www.youtube.com/watch?v=YZ0pKZwfCUU)

et al 2004) of environmental degradation appeared, which in turn led to a drop in productivity. The papers by Zheng et al and Dietrich et al lend support to this hypothesis.  With increasing demand for food accompanied by local overexploitation of resources, the time (and the energy) spent in collecting food increased (larger distances had to be travelled); the old food production system became unsustainable, and humans were actually forced into the neolithic revolution, as the pressure of environmental changes, population density and shortage of labour became excessive. Interestingly, there is some evidence (Stevens and Fuller 2012) in Britain that farming arrived around 4000 cal BC, but that it did not last very long. Instead, between  3300 and 1500 BC Britons reverted to pastoralism. The article mentions that This loss of interest in arable farming was accompanied by a decline in population. Again, it is not obvious whether population is driving cropping or the other way round, but the article could mean that when agriculture was no longer needed because of the population decline, humans became herders again!  Apparently, the great megalithic monuments were built around that time (note 10).  

The passage from hunting and gathering to a new system was a relatively obvious and fast one, though not necessarily easy. In other words, the food production system may have become unsustainable, but the society as a whole adapted to the new situation by resorting to exploitation of accumulated innovations.

I very much believe in the role, and even the necessity of “disasters” (extreme events) to force humans to make greater use of marginal technologies, thereby turning them into “innovations” (Haberle and Chepstow-Lusty 2000. Also see this post). A priori, what is an innovation, or which innovations are important, is difficult to say. Cipolla (2003) confirms this, in a completely different context: innovations, when they first appear, are less important for their immediate advantages than for their potential to stimulate future developments, and that this second, intangible, attribute is always extremely difficult to value.

The chain extending from “neutral” innovations through environmental and societal stresses to the eventual adoption of innovations is one of the basic mechanisms of sustainability. In the same way as hotspots are characterized by an accumulation of environmental and societal stresses, an accumulation of innovations is required to precipitate development into a new direction.

What happened during the early Neolithic? Driven by unknown forces (favourable climate?) human populations started expanding and unsustainably exploiting their environment.  They had no option but resort to technology they had known for a long time and turn a hobby into a job, i.e. they invented agriculture… and crops and livestock must have started competing soon!  The story of Cain and Abel has always puzzled me: why would God prefer the sheperd to the farmer? Because he was obviously a meat-eating or a meat-eaters’ god. The story may have been the first rehearsal for range wars (note 11).

There is probably a lot of truth to this statement... Source: http://www.huffingtonpost.com/2013/04/05/beer-facts-trivia_n_3016246.html

There is probably a lot of truth to this statement… Source: http://www.huffingtonpost.com/2013/04/05/beer-facts-trivia_n_3016246.html


Note 1. Ploughing is a sophisticated form of land preparation; it is not indispensible, as demonstrated by the growing appeal of no-tillage and low-tillage. Land preparation also includes elimination of previous years’ plant residues (including weeds) to bare the soil and to eliminate competing plants.

Note 2. An early version of this post was published as Gommes, 2004. The original short paper can be downloaded here.

Note 3. A domesticated crop is a crop in which selection by man has developed some desirable traits, including mostly  larger and heavier grains than in the wild species, as well as “a non shattering rachis”, i.e. the plant does not spontaneously drop the seeds (grain) once they mature. Instead, they remain attached to the spike and need a human intervention (i.e. threshing) to separate from the plant.

Note 4. BP stands for “before present” or, sometimes “before physics”. The reference date is 1950. See wikipedia.

Note 5. Grinders and pounders have been known from the upper Palaeolithic (between 45000 and 18000 BP); they were used for pigments and medicines of mineral, plant and animal origin. Toussaint-Samat lists the first grain mills as being from around 13000 BP, but Piperno and her colleagues recovered starch from the stones; they were indeed millstones.

Note 6. Mixing a cereal with yeast and water is also the receipe for beer! There is a close link between the histories of bread  and beer. This has been addressed  for instance by Toussaint-Samat (1997).

Note 7. There are, in fact, several passages in the Bible where barley is sold at half or one-third the price of wheat (2K 7:1, 16, 18).

Source: http://www.etimo.it/?term=polenta&find=Cerca

Note 8. “Pulte”, a word which we find also in “polenta”. See this link for the history of polenta.

Note 9. Jeunesse (2008) wrote a short but dense article about prehistoric innovation. He stresses the fact that many inventions that we regard as “innovations” have actually been around for centuries before their use exploses, often for poorly understood reasons.

Note 10. Göbekli Tepe too was built by pastoralists/hunters. One wonders if the construction of those  major structures, which required huge labour inputs, could possibly have been built by crop farmers. Crop farming is much more location bound than herding. It seems actually unlikely that crop farmers could have abandoned their farms over long periods of time to go and help built Göbekli Tepe or Stonehenge. Somehow, one might even imagine that the large investment in metaphysics was not compatible with cropping! There are other examples: during the Little Ice Age, Norse populations in Greenland  invested a lot of energy in building wooden churches… instead of protecting themselves against Eskimos (McGOvern, 1981).

Note 11. I cannot help thinking of the famous (and probably apocryphal) quote “Let them eat cake.” When told, during the French revolution, that the people of Paris were rioting because there was no bread, the queen is alleged to have said “Let them eat cake”. When I apply this to the current post, we probably have a period when hunter gatherers were eating cake during huge popular celebrations… until they ran out of food and increased the production of bread!


Banning EB 2011 So Fair a House: Göbekli Tepe and the Identification of Temples in the Pre-Pottery Neolithic of the Near East. Current Anthropology 52(5): 619-660

Badr A, Müller K, Schäfer-Pregl A, El Rabey H,Effgen S, Ibrahim HH, Pozzi C,Rohde W, Salamini F 2000 On the Origin and Domestication History of Barley (Hordeum vulgare)  Biol. Evol. 17(4):499–510

Craig OE, Steele VJ, Fischer A, Hartz S, Andersen SH, Donohoef P, Glykou A, Saul H, Jones DM, Koch E, Heron CP 2011 Ancient lipids reveal continuity in culinary practices across the transition to agriculture in Northern Europe. PNAS 108(44):17910–17915 and and http://www.sciencedaily.com/releases/2011/10/111024153407.htm

Cipolla CM 2003 Vele e cannoni. Bologna, Italy: Il Mulino. 174p. Translated from Guns and sails in the early phase of European expansion, 1400–1700. London: Wm Collins & Sons % Co.

Dai F, Nevo E, Wu D, Comadran J, Zhou M, Qiu L, Chen Z, Beiles A, Chen G, Zhanga G 2012 Tibet is one of the centers of domestication of cultivated barley. PNAS 109(42):16969–16973

Dietrich O, Heun M, Notroff J, Schmidt K, Zarnkow M 2012 The role of cult and feasting in the emergence of Neolithic communities. New evidence from Göbekli Tepe, south-eastern Turkey Antiquity 86(333):674–695. Also see this link to Dienekes’ blog.

Eckardt NA 2010 Evolution of domestic bread wheat The Plant Cell 22: 993

Gommes R 2004 Bread – innovation, serendipity, necessity – via hotspots of environmental degradation, gruel and sustainability. European Society of Agronomy Newsletter, 25: 43-44

Gommes R, du Guerny J, Glantz MH & Hsu, L-N 2004 Climate and HIV/AIDS: A hotspots analysis for Early Warning Rapid Response Systems. UNDP/FAO/NCAR, South-East Asia HIV and Development Programme, UNDP, Bangkok. 24p. Download it from here.

Haberle SG & Chepstow-Lusty A 2000 Can climate influence cultural development? A view through time. Environment and History, 6: 349–369

Jacob HE 1954 Sechstausend Jahre Brot. Hamburg, Germany: Rowohlt Verlag. 502p

Jeunesse C 2008 Une théorie de l’invention préhistorique. La Recherche 418:46-50. Also: http://www.larecherche.fr/content/recherche/article?id=23045

Kuijt I, Finlayson B 2009 Evidence for food storage and predomestication granaries 11,000 years ago in the Jordan Valley. PNAS 106(27):10966–10970

Lawler A 2009 Millet on the move. Science, 325:942-943. According to recent findings, it seems that millet used to be a much more import crop than rice in ancient China

Lu H, Zhang J, Liu K,  Wu N,  Li Y,  Zhou K, Ye M,  Zhang T,  Zhang H,  Yang X,  Shen L, Xu D, Li Q  2009 Earliest domestication of common millet (Panicum miliaceum) in East Asia extended to 10,000 years ago. PNAS 106(18): 7367–7372. Downloadable from http://www.pnas.org/content/106/18/7367

Mazoyer M, Roudart L 1998 Histoire des agricultures du monde, du néolithique à la crise contemporraine. Paris: Editions du Seuil. 545p

McGovern TH 1981 The economics of extinction in Norse Greenland pp 404-430 in Wigley TML, Ingram MJ, Farmer G 1981 (editors) Climate and History, Studies in past climates and their impacts on man, Cambridge University Press 532 pp  Republished 2011

Piperno DR, Weiss E, Holst I, Nadel D 2004 Processing of wild cereal grains in the upper Palaeolithic revealed by starch grain analysis. Nature, 430: 670–673

Stevens CJ, Fuller DQ 2012 Did Neolithic farming fail? The case for a Bronze Age agricultural revolution in the British Isles. Antiquity 86(333):707-722. http://www.antiquity.ac.uk/ant/086/ant0860707.htm

Toussaint-Samat M 1997 Histoire naturelle et morale de la nourriture. Paris: Larousse. 958p

Zheng HX, Yan S, Qin ZD, Jin L 2012 MtDNA analysis of global populations support that major population expansions began before Neolithic Time. Nature Scientific Reports. 8 pp. http://www.nature.com/srep/2012/121018/srep00745/full/srep00745.html and http://www.sciencedaily.com/releases/2012/10/121018130834.htm

Zohary D, Hopf M, Weiss E 2012 Domestication of Plants in the Old World: The origin and spread of domesticated plants in Southwest Asia, Europe, and the Mediterranean Basin (4th edition)Oxford Univ. Press, 243 pp + appendix with illustrations.

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11 years ago

Excellent texte. J’aime beaucoup la “néo-paléontologie”, qui redessine tout, que ce soit les dinosaures ou nos ancêtres, de façon beaucoup plus détaillée et bien plus cohérente que l’historio-paléontologie “politique” de Napoléon III et consort.

Du temps de la Bible, les graines d’épeautre étaient *germées*, avant d’être broyée et cuites et pain.

Le gluten ; la protéine du blé, est relativement indigestible. Au mieux les intestins apprennent à la tolérer. Il parait que la raison principale pour laquelle la pâte à pain doit être pétrie et re-pétrie pendant des heures, est que l’allongement continuel de la pâte pendant le pétrissage étire/déroule les molécules de gluten, ce qui favorise leur rupture et donc favorise grandement leur assimilation finale.

L’invention de la meule flottante a allongé la durée de vie des humains parce qu’elle permettait aux mangeurs de pain de garder leurs dents plus longtemps. Avant, de minuscules éclats de meule étaient mélangés à la farine et usaient prématurément les dents.

C’est très intéressant la réflexion sur le fait que le pain se conserve. J’ai vu du pain de campagne se conserver deux semaines sans efforts… Du pain compact et fumé devait probablement se conserver deux mois ou plus. À comparer avec les baguettes de “pain” français que les industriels nous refilent à présent, qui tiennent moins de 24 heures… Sans parler des “meules” modernes qui tournent à très grande vitesse et éclatent les grains par choc, en générant brièvement de hautes températures qui modifient la chimie de la farine.

C’est très intéressant de supposer que l’agriculture s’est développée pour répondre à la croissance démographique et pas le contraire. Tout comme les champs de blé se sont développés “en Wallonie” pour répondre aux besoins de l’armée romaine, avec à la clé l’invention de la première moissonneuse.

Il est inévitable que Göbekli Tepe était religieusement fondé puisque à l’époque *tout* était religieusement fondé. Petit au grand, tout endroit avait son culte, son ou ses prêtres… Un ami se passionne pour le Cambodge et ses habitants et apprend à vivre avec les gens. *Tout* ce qu’il font, ou ne font pas, est articulé autour de pseudo-raisonnements superstitieux. La “religion” est d’une certaine façon les superstitions de l’élite. Elle sont plus générales, plus intellectuelles… éventuellement imposées au peuple qui n’y comprend pas tout…

Je le sens bien, que le néolithique a été drivé par les besoins démographiques. Mais notre actuelle démence démographique, elle va engendrer quoi ? Des pays qui ne sont plus qu’une grande ville et on plante du blé sur les toits ? Cela entraîne quel ordre social ? J’ai un ami qui a des brevets dans les toitures vertes. ‘Faut que je lui envoie ton article… Une autre réponse, que tu donnes ailleurs, sont ces pays qui achètent de la terre cultivable dans d’autres pays. Du néocolonialisme, plus pour des minerais précieux ou des essences rares mais… juste pour pouvoir planter du blé ou du maïs et avoir à manger…

La médecine moderne a une influence non négligeable sur la question. Avant, tu étais peu ou prou obligé d’acheter les denrées issues d’un lieu, aux personnes qui habitent le lieu. Et de les respecter, pour que la situation soit durable. Parce que, tu ne pouvais pas occuper le lieu toi-même, parce que tu ne lui étais pas adapté. Exemple tarte à la crème : chaque région d’Afrique a ses variantes propres de la malaria. Une personne née dans une certaine région, développé une réponse immunitaire mais uniquement contre les variantes locales de la malaria. Si elle voyage, elle se retrouve fragile face aux autres variantes, des autres endroits. Donc chacun tend à rester chez soi. Si tu vas chercher misère à des gens trop éloignés, les “esprits” qui hantent les lieux vont te vider de ton tonus vital…

11 years ago
Reply to  Eric

Merci, Eric!

Deux petits commentaires

1. Tu dis “Du temps de la Bible, les graines d’épeautre étaient *germées*, avant d’être broyée et cuites et pain.”

Pas que du temps de la bible… Il y a beaucoup de peuples qui germent les céréales avant de les consommer. C’est d’ailleurs un lien avec la bière (l’orge et le malt)! Souvent aussi, on germe ET on fermente les grains. Les Ghanéens fermentent le mais (qui s’appelle chez eux Guinea corn) avant d’en faire du cake (qui s’appelle, comme de juste “corn cake”). C’est horrible comme goût, mais supportable, comme un mélange de vinaigre et de pain moisi. Les Ethiopiens fermentent le teff avant de faire la injera. Le gout se rapproche de celui (enfin, de l’odeur) d’une lavette à vaisselle non lavée pendant deux semaines (= fermentation butyrique). Au début, je faisais un effort pour ne pas vexer la personne qui m’offrait à manger… et j’avais l’estomac retourné pendant deux jours. Après, j’ai mangé des patates!

2. “Il est inévitable que Göbekli Tepe était religieusement fondé […] ”

Je suis bien d’accord que religion=pouvoir… il suffit de se souvenir de nos cours d’histoire et de lire lire la presse pour s’en rendre compte plus près de nous! Mais dans le cas de Göbekli Tepe, certains (Banning) ne sont pas entièrement convaincus!

11 years ago
Reply to  Eric

La question dents et meules. Il est bien connu que les dents étaient usées précocement par les éclats de pierre, mais il y avait tellement de causes de mortalité que je ne pense pas que cela a diminué de façon notable l’espérance de vie. De nombreuses populations se servent de leurs dents dans la vannerie, le travail des peaux… et cela use bien les incisives, mais les dents restent. Je ne parlent pas de ceux, statistiquement insignifiants qui vont “chercher la croissance avec les dents”!
Deux remarques anecdotiques: l’état des dents est un indicateur du statut social des squelettes chez les étrusques: la plebs avait les dents usées par les éclats, les riches perdaient leurs dents parce qu’ils mangeaient peu de choses dures… Les jeunes filles paysannes pouvaient se faire arracher des dents pour valoir plus pour leur mariage: économie de frais et d’ennuis pour le futur mari! Ce n’était pas la norme, mais j’ai lu que cela existait là où la dot était importante.

11 years ago

The star graphic certainly applies to “pre-inventions”! Perhaps it could be combined with the systems approach of Jared Diamond which is sort of too flat over time and can capture constellations of factors and inter-relations, but not so well slow processes.
You seem to adopt a more Boserupian approach and the quarrel with Malthus has gone on, but as the previous comment shows, it is all at the same time over a long period. I think there is a misunderstanding on the Neolithic ‘revolution’ linked to a misrepresentation of slow processes: there is no Eureka and producing the first Neolithic baguette. The inventions took place over 100-200 generations and quite a large area through observations, chance and transmission, advancing here, regressing there… How can one find traces of this?

You are very right in stressing how difficult the first ‘inventions’ were to make, to interrelate and build upon. Boserup who was a very remarkable person and had a profound influence somehow inherits a rather mechanistic approach from mid century economics which ignores the slow time over a long period… Before one reduced their mortality, slash and burn societies were quite stable: the possible population pressure was corrected by mortality and adjustments could be made on the areas slashed and burnt. In modern times population pressure led to out migration and environmental destruction…rather than innovation. But the difference is that the societies had no time to really invent or adjust! One can also imagine as you say, wheat grew nicely near the houses because of manure… and the grass was also used to light fires… some people would notice that the grains were roasted in the ash or lying on flat hot stones… One could also wonder if pastoralism is not similar to slash and burn: the herds graze and move on then return; and this could have slowed the development of agriculture.
So, the seeds of change operated very slowly, but are not visible to our eyes although the last few years one has begun to see certain things, and what we call the Neolithic revolution is when the situation was ripe enough for us to see it, like the aorist in ancient greek: le résultat present d’une action passée. Just like I have always argued that the dispersal of humans happened long before and am happy to see signs of confirmation. However, one could not see it, one could only see concentrations.

Anna Giulia
Anna Giulia
11 years ago

Thank you for this article.
I was fascinated by the theory of Levy-Strauss on the origin of cooking foods, by the aspect of the original maize, and by the redundant ploidy of wheat. There is general agreement that the cooking of food, as the domestication of plants and cattle, began in the Neolithic. The need for pottery, the analysis of archaeological remains and the findings of the molecular and population genetics suggest this period. However, even the most appealing features of this history have their dark side. The so called “domestication syndrome” includes more appealing organoleptic features, higher nutritional properties and (at least in animals) lesser aggressiveness, obtained at the price of a very low survival and reproductive potential, if the species is returned to the original wild conditions.
During the Neolithic the Homo sapiens was the only survival of all the species of Homo: had the different species domesticated each other? Is this the disquieting property of our species, or perhaps of the entire Genus, the ability not only to get slaves, but to modify them in order to induce the extinction of the less appreciated living beings?