The sheep and goat breeding process started from 9000 to 8000 BC in southwestern Asia. The site of the early Neolithic in Aşıklı Höyüku in central Turkey retains early archaeological evidence of this transformation, such as age and sex removal and the use of fenced spaces within the settlement. Human caprine management strategies have developed at this site over a period of 1000 years, but changes in the scale of practice are difficult to measure. The fertilizer and the hidden layers in Aşıklı Höyüku are highly enriched by the values of soluble sodium, chlorine, nitrate and nitrate nitrogen isotopes, a pattern that humans and animals mostly attribute to urination. Here we present an innovative mass balance approach in the interpretation of these unusual geochemical patterns that allow us to quantify the increase in the management of goat hair over a period of 1000 years, which should be applicable to other arid countries.
It is believed that the conversion from hunting and harvesting to breeding and breeding occurred between 9000 and 6500 BC in southwestern Asia, during the neolithic period before pottery. Human caprine management (sheep and goats), together with pigs and finally stock, is one of the first manifestations of socioeconomic change in southwestern Asia (1–3), with the addition of grain and legumes. Aşıklı Höyük (4–6) in Eastern Central Anatolia (Fig. 1, insert) keeps early evidence for manipulation of sheep and goats in humans according to 8450 BCE7. 8) and local evolution of these practices over the next 1000 years (about 8450 to 7450 BC).
Aşıklı Höyük is located on the extended part of the Melendiz River, where in the late Pleistocene swamps deposits developed a rich soils suitable for plant breeding (9). The settlement has become permanent in just a few generations (6). Local process of wheat domesticization (10), and residents have experimented with the propagation of honey from earlier (7). The first human occupations in Aşıklı Höyüku (Level 5) were located directly on the natural main stream of alluvium (6). Until the last period (Level 2), the area covered an area of approximately 57,000 m2 and rose to ~ 16 m above the floodplain of the Melendiz River. Erosion by river meandrage and 30 years of archaeological excavations (4. 5) created exceptional vertical and lateral exposures of deep archaeological layers and natural algae (Figure 1). Levels 5 and 4 range ca. 10.400 to 10.000 calibrated years before the present time (cal BP) (mid to late 9th millennium BC), level 3 extends from 10,000 to 9700 cal BP (late 9th to early 8th millennium BC), and level 2 extends from 9700 to 9300 cal BP (early) by the middle of the 8th millennium BC) (8). From the originally wide and varied diet in Level 5, reliance on people on caprines and cultivated grains and legumes has gradually increased from Level 4 to 2 (7. 10. 11).
The oldest occupation at Aşıklı Höyüku at Level 5 may not have been completely over, and buildings and other buildings were relatively fragile. The residences were oval semi-underground structures built of wicker and pile and separated from one another on the outside surfaces where there were layers of waste called middens, small enclosures and working areas (6). Level 4 contains buildings of a similar design, but the walls are made of sunny sands and are more massive. Architectural transition from oval semi-urban buildings to overhead quadrilateral buildings takes place within level 3, with significant growth of discovered deposits and surrounding areas. Level 2 shows a marked consolidation and filling up the architectural space on the hummingbird, when the animal houses disappear from the top of the hill, but the overall dependence on goat's meat has continued to grow. The internal and external space within the settlement was approximately the same in Levels 5 and 4, but moved to a larger internal space during Level 2 when multiple works were done in indoor or high flat roofs of residential buildings. The building grouping also became present during Level 2, with narrow streets that separated the dense architecture. Construction clusters created neighborhoods, and almost every neighborhood had its own hidden area (12).
Most of the landfill consists of buildings and construction residues, predominantly muddy and plaster, and middens (6. 8). Middens and small dumps contain a variety of sediments with animal bones, primary and burned plant material, carrots and mortar, pus, wood ash and a rich assortment of opiates and other artifacts. Middens at level 2 appear as (and) well-limited, heavy waste concentrations, called "communal middens," where a wide range of activities such as meat, animal and work burial, and (ii) dispersed waste disposal areas existed. Landfills and hidden sites are at least concentrated in levels 4 and 5, where they are mostly located in the depressions of abandoned half-timbered buildings (13). The rate of waste accumulation rose to the younger levels as the community increased in size and scope of building mudbrick stone.
Place Aşıklı Höyük provides a rare opportunity to examine the developmental subtlety of the first stages of the homemade process in one place[([([([(14) but look at and (7. 8. 15. 16)], Human caprine management is marked by architectural remains of floats and coral fences (6); micromorphological evidence of concentrated primary fertilizer that the animals are gazelle13), often within recognizable enclosures; Zooarheological evidence of selective removal of young male goats before the age of 6 to 7 months (7); and phytolithic, macrobotan and isotopic evidence of on-farm animal feed (10. 17. 18). The practice of keeping sheep and goats in captivity has started at a very small extent at level 5, and archaeological evidence shows that it has grown over time. The economic dependence of caprine population in relation to other sources of meat has increased from about 26% of all animal remains at levels 5 to 92% in later stages of level 2 (7. 16). Pathology of joints suggests that animals were excessively closed during periods that represent levels 5 to 3, and less during time 2 (17). Increased rates of joint pathology suggest that animals are in most cases written. Outer citizenship did not begin in the later series (Level 2), but mostly from April to November, as the region experiences heavy snow in the winter months. Night penning was probably practiced at all times due to the prevalence of leopards, bears and wolves in that area (7) and near or completely absent dog guard.
Zooarheological, palaeobotanical and architectural data from Aşıklı Höyüka therefore show that human management strategies for capers have experienced significant evolution over the 1000-year period. However, from these conventional archaeological data, it is very difficult to measure the scale of practice. In this study, we have developed a new and independent test for the initial reconstruction and changes in the time-scale storage bases based on the chemical composition of soluble salts in archeological sediments, especially urine salts as substitutes for the field of human metabolic activity. Micromorphological examination and Fourier's infrared spectroscopy of medium and structural materials revealed the presence of numerous salts, including nitrile crystals (NaNO).3), an odd mineral that is usually found in extremely dry, salty environments (19) Rich Na+ and NO3– (Fig. 2 and Fig. S1). This mineralistic strangeness first encouraged us to investigate the soluble salt (Na+Cl–, NE3–, SO42-, K+, Ca2+and Mg2+) and isotopic nitrogen composition that could explain the presence of nitrates.
Here, we describe the above-described approach to the interpretation of the geochemical composition of the archaeological description and its implications for the early domestication of animals. The soluble salt composition weighs more than 100 samples as a function of material type, position in humans and ages (Table S1). For the purpose of this paper, we mainly focus on the patterns it displays[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]which in archeological layers achieve unusually high levels which are only partially explained by sources such as precipitation, wood ash and natural sediments built into building materials. In addition, we analyze nitrogen isotopes to identify the source of soluble nitrogen.
Our key finding is that the urine – from equidae and humans in combination – gives the best explanation for the unusual mineralogical composition and composition of salt. We present a simple mass balance model that provides limitations on the scale of change in the number of caps and people who have lived for more than 1000 years of uninterrupted occupation.
Soluble salt concentrations
We analyzed the soluble salts of 113 samples (see Methods) from three excavated areas: 4GH or "deep probe" on the north side of the slope, area 2JK (or "west wall") toward the Melendiz River, and, finally, the "Southern Transet" side (Fig. 1). generally,[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–](expressed as mean value  in moles × 1000 kg-1 ± 1σ SD) vary greatly in sediments in Aşıklı Höyüku, from very low levels in natural, nearheologic alluvium below place to size (on average over time) in overhead archaeological layers. Of all the examined material types, general hidden samples (n = 51) contains the most[On[On[Na[Na+](4.44 ± 4.80),[Cl[Cl[Cl[Cl–](6.86 ± 9.58), i[NOT[NO[NE[NO3–](3.73 ± 8.32) (Figure S2 and Table S2). Samples rich in dung and compacted dungn = 9) also show an elevated[On[On[Na[Na+](1.47 ± 2.08) i[Cl[Cl[Cl[Cl–](1.61 ± 2.51) but much lower[NOT[NO[NE[NO3–](0.105 ± 0.280) compared to the average in general. Samples from the alley between buildings at level 2 (n = 9) contain relatively high levels of all three ions. Building waste consisting of brick, gypsum and floor materials (n = 9) contain concentrations of soluble salts ranging from ~ 2 to 50 x less than the samples with general and scanned specimens (Table S2). Finally, the samples inside and below the hearth can not be chemically distinct from wild wild species. Hidden patterns, which consist of material from the general hidden, wild species, and the alley, also show significant spatial heterogeneity [1σ relative SD (RSD) of >200% of the mean in some cases] across horizontal units (here as example uses level 2) in[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]content (table S2 and image S3).
By contrast, natural aluvium below level 5 in the western part (area 2JK, n = 8) and 4GH (n = 13) (Figures 1 and 3) contain the lowest salt concentrations in relation to all classes of archaeological material.[On[On[Na[Na+]from the podarheological aluvium in the 4GH area (0.459 ± 0.167) and the area of 2JK (0.198 ± 0.125) is about 3 to 10 × smaller than the ones found in the fireplaces, the fertilizing and construction residues and ~ 15 to 20 × less than the alley generally concealed samples.[Cl[Cl[Cl[Cl–]and[NOT[NO[NE[NO3–]they are still lower compared to the archeological material for the factor of 2 to 60 × or from 3 to 400 × (Table S2). Salt concentrations in the natural alluvium below the embankment are also much more homogeneous than those in archaeological layers (1σ RSD <150% mean) (Table S2).
[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]broadly, vertically and sideways, within archaeological levels, in accordance with the spatial division of activities in the settlement. For example, in 3rd degree refuse[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]vertically vary by about 5 times between fine vertical layers in the 4GH area (Figure 3). Side by side, variability in[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]within Stage 2 may also differ in order of magnitude from generally much lower values in 2JK samples dominated by residential buildings to higher levels in areas where garbage is dominated by 4GH and southern transits (Fig. S3). As an example,[NOT[NO[NE[NO3–]in the 4GH area shows a mean value of 9.77 ± 6.85, ~ 20 to 45 × greater than that of 2JK (0.522 ± 1.04) and south transsex (0.204 ± 0.316).
On a rough scale, the averages of[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]Increase vertically through time from level 5 to 2 (figure 4). There is an increase of 5 to 10x[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]from Levels 5 to 4 and 10 to 1000x increases from Levels 5 to 3 (Figure 4).
We have solubilized NO3– out of 51 midden samples for δ15N analysis (Table S1). Twenty-one hidden sample and all except one basal natural alluvial pattern [table S1, AHJQ-818-2 (IIIB)] there was not enough material (table S1) for the analysis of the isotopes after the curing. All hidden samples returned δ15Nsoluble value [expressed as the population mean (μ), followed by the range] +13.2 per mil (,), + 5.8 to + 17.7. Among them, samples of general concealed (n = 41), the hidden divisions with the domination of manure (n = 3) and alleys (n = 7) returned the most δ15Nsoluble (+ 13.2 ‰, +5.8 to +17.7 +, + 14.2 ‰, +9.5 to +17.1 and, and + 12.4 ‰, +9.1 to +17, 2 ‰, respectively). Building waste (n = 4) shows a narrower and lower range than δ15Nsoluble (+9.0, +7.0 to + 11.2 ‰), as well as fires (n = 8; +8.2, +5.5 to +12.0 ‰). Nearheological Modern / Pleistocene Flood Sediments (n 3) outside the humus, which was sampled to represent natural aluvium, gave a significantly lower value δ15Nsoluble values (+5.4, +2.3 to +7.8 ‰).
Modeling of soluble salt sources
Sources of soluble salts. The rich soluble salts found in almost all archaeological layers in Aşıklı Höyüku are most likely to have more natural and anthropogenic sources, and our goal is to isolate the anthropogenic (human and animal) salt component that can not be explained by other sources by building a simple mass balance model. Total salt concentration I (CTot I) (S4A) at any level in Aşıklı Höyük can be divided into those salts inherited from parental alluvial material (Cinherited I) by incorporating construction materials, salts of added anthropogenic (humans and animals in captivity) during ~ 1000-year occupation of humus (Canthropogenic I), and those that were subsequently added by rain (Cpostdepositional I) in a period of 10,000 years, so
(1)where C is the concentration of chemical species I expressed in molars per cubic meter in each component.
Cinherited I consists of building and construction residues that are probably (at least initially) made up of the surrounding natural aluvium. The construction component of construction waste (CTot cd I) humock can be estimated based on the chemical composition of the local, nearheological aluvium. Excavations between 2015 and 2017 in Aşıklı Höyüku reached a distance of 1 to 2 m below the ground floor at a wide area, revealing undisturbed floodplain sediments set before the first occupation of the site. These sediments are dominated by layered sludge and mud with smaller sand and diatomaceous earth. Our analysis reveals that the salt content is Cinherited I the alluvial material is uniformly low, averaging 11, 29 and 294 × less in soluble Na+Cl–and NO3–in relation to archeological waste (all considered samples). Namely, the aluvium is extremely low in salt soluble form (S4B). This difference is easily seen in great contrast between these elements through archeological / natural aluvial contact in the part of the 4GH region (Figure 3). In our calculations we suppose[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]is equal to the average value of the natural building waste (table S2 to S5). These concentrations, with moles per kilogram units, are converted into our working concentrations (CTot cd I) over a cubic meter multiplying by the density of construction waste (Table S6), as determined in this study, and a fraction consisting of worn construction materials (see Supplementary Material for Explanation of Acceptable Value). We do not use the values of brick and mortar concentrations measured for this study since many of them, especially at later levels, were generated from recycled mills, which is probably the reason for their high salt solubility (S2), and thus do not point to the legacy , local natural material.
Canthropogenic I includes herbal substance, bone and wooden ashes. We can calculate the contribution of these components Canthropogenic I for a particular chemical type I using their individual salt concentrations, their density and their partial contribution to the total amount of salt. The first two terms can be estimated from the literature (see Supplementary Materials), and the third is defined in this study (see Supplementary Materials). Wood ash, bones and plants are the main SO sources42-, PO43-, Ca2+, Mg2+, K+and CO32-, but less contribute[On[On[Na[Na+](~ 63%),[Cl[Cl[Cl[Cl–](<0.1%), i[NOT[NO[NE[NO3–](~ 6.6%) of inventories at the site (table S3 to S5). Fragments of the bones are separated by dry sieving, and the decomposed plant material in the micrometer scale should contain a small amount of soluble salt. As such, they are not taken into account when calculating the mass balance. Wooden Ash (Cash I) is a major potential soluble salt partner because it accounts for ~ 25% of waste wastes (see Supplementary Materials). Wood combustion creates alkaline ash containing K+, lime and other nutrients20). Using average combustion temperature (21) of general wood ash (of wood and bark) which falls within the range of those identified from wood species near Aşıklı Höyük (22–24), the average content of soluble salt obtained from wooden ash (Table S3 to S5) can be calculated (21. 25. 26).
Postdeposic sources (Cpostdepositional I) salts are delivered with rain and aerosols containing different concentrations of dissolved substances depending on the ocean and atmospheric circulation (27. 28). The growth of industrial age in sulfur oxides and nitrogen oxides in atmospheric waters should have little impact due to the short history of industrialization. In order to best present 10,000 years of deposited rainfall on site, we used contemporary values from unwashed locations in continental interiors around the world to Cpostdepositional I (also Crain I) (28). Total rainfall in total soluble salt species (CTo train I) is calculated based on the assumption of exponential drop precipitation / groundwater salt, modeled on the soil chlorine data presented by Sandvig and Phillips (29). Additional variables are occupation time, depth intervals of different archaeological levels, annual rainfall and presumed runoff ratio.
Estimates for Crain I are obtained from the literature as well as the annual precipitation rate (R) 0.4 years-1 (tables S3 to S5). We have chosen a conservative rainfall (α) ratio of 0.1 as this is the average for most sand / sands horizons on low slopes. Further materials are examined in more detail on the pattern of runoff time and rainfall depth.
By that time this modeling assumes Cinherited I = CTot cd I. Canthropogenic I = CPeak ash I and Cpostdepositional I = CTo train I, With the estimates for all the terms in our mass balance equation we can calculate the remaining soluble salts within the humus that are not explained by our known sources (Cresidue I)
This adds to the contribution of all these precipitous and well-known postdeposic components (CTot cd I + CPeak ash I + CTo train I) and is deducted from the total salt inventory (CTot I) (Figure S4A) to calculate part of the unexplained salt (Cresidue I(Fig. S4C) according to the precipitation and post-epoxy components described so far. Using the average, we find that Cresidue I is negligible for four soluble salts (SO42-, Ca2+, K+and Mg2+) because this can be reasonably explained by inlets from atmospheric and anthropogenic sources
By contrast, the average soluble[NOT[NO[NE[NO3–].[On[On[Na[Na+], i[Cl[Cl[Cl[Cl–]archeological layers do not describe almost atmospheric or anthropogenic sources
We can express proportions Cresidue I to CTot I partly as a percentage. Substituting
for species I in all precipitation and known postdepositive terms in Jed. 2, calculate that%the residue of Na = ~ 25%,%the residue of Cl = ~ 95%, i
= ~ 88% (based on average samples of municipalities / fertilizer and various samples from all levels, which means that certain levels may have a higher or lower level)residue I). The above calculations are used to determine the contribution of each component CTot I in cubic meters per cubic meter. The sensitivity of the model results to uncertainties in the various components of the mass balance model is described in Section S11.
Urine contribution?. Proportions On+ (12%), no3– (27%) and Cl– (61%) Cresidue I Derived from our calculations have a strong resemblance to the most abundant ingredients, NE3– (derived from total N), Na+and Cl–, human and goat urine (S4D and S3 to S5) (30. 31), especially if nitrate concentrations are corrected for the evaporation of ammonia. Increased δ15Nsoluble The values (+ 13.2 +, + 5.8 to + 17.7 ‰) of the hidden samples are unusual and provide critical evidence for the origin of urinary origin N in wastewaters in Aşıklı Höyük. It is known that nitrates and other salts accumulate in dry soil soils below the root depletion depth of most plants but δ15N values of these nitrates range from 0 to + 10 ‰, too small to calculate higher values recorded in Aşıklı Höyük (32. 33). Moreover, salt concentrations in Aşıklı Höyüku differ significantly in the tiniest measure of tens of centimeters from bed to bed, as opposed to a smoother reduction in the concentration of salt with depth under natural soils (32. 33). High δ15N-values can naturally develop in soils in the aquatic body by denitrifying the bacterial reduction of NO3– (34. 35), but there is no evidence of a chemical reduction of well-drained and dry sediments that form an integral part.
High δ15Nsoluble values> 10 document are well documented at places where animal waste and their degradation products are concentrated (36). For example, the highest biogenic δ15Ever-recorded values (> + 49) were found in the Antarctic Penguins (37); elevated δ15N levels ranging from +7,4 to +13 ‰ are limited to the ground and nearby ponds in the ponds (38). Sessions on which industrial fodder wings are found provide numerous examples of the impact of animal waste on ground chemistry under the fenced spaces, well-studied for local groundwater contamination (39. 40). There are great similarities between highs[NOT[NO[NE[NO3–]and δ15Nsoluble values in rejected Aşıklı Höyük compared to reported data from five modern39–41). Atmospheric rain and N2 fixation, fertilizer, natural soil, waste water and waste of animal waste are presented in the feed class system δ15N ranges from -15 to +2, -5 to +12 ‰, +2 to +9 ‰, +5 to + 19 ‰ or +7 to +26 ((Figure 5) (39–43). Animal waste is the largest δ15N values, the effect of the ammonia vaporization process discussed below. Range δ15Nsoluble values from Aşıklı Höyüka are closest to the mean value of animal waste, but also within the total range of human sewage (Figure 5).
The number of soluble salts in modern pastries also recalls the vertical patterns observed in Aşıklı Höyük. Fogg et al, (40) documented at a depth of ~ 20 m,[Cl[Cl[Cl[Cl–]and[NOT[NO[NE[NO3–]under modern dairies in California they range between ~ 100 and ~ 1000 parts per million (ppm), which is significantly more than just 1 to 50 ppm in natural soils outside the diet area. Similarly,[Cl[Cl[Cl[Cl–]and[NOT[NO[NE[NO3–]of midden, with bark bears and alleys in Aşıklı Höyük range from ~ 1 to ~ 28,000 ppm (mean, ~ 1800 ppm) but only from ~ 1 to ~ 250 ppm (mean, ~ 36 ppm) in natural below the place.
In short, we conclude that in samples of common hidden, hidden game and alley, Cresidue I ≈ Curine I. based on a strong similarity in salt geochemistry and δ15Nsoluble values between layers of modern educational facilities and those in Aşıklı Höyük.
Both human and sheep feces also contain all the salts discussed so far. However, manure is not considered in our mass balance calculation nor in our model used to estimate the population of the organism. One of the reasons for this is that> 99% of total chlorine and> 80% of total sodium output for sheep in urine (44). As such, it is unlikely that the mud contributed more than 20% of the total Cl– and Na+, Nitrogen is greatly changed in sheep's milk and urine, and can contribute up to 50% of total nitrogen (45). However, the forms of nitrogen found in the balm are less soluble than those of the urine and can reduce the contribution of the soluble manure NO3– (45). This may explain why all concentrations of salts in the fertilizer prevailing samples are lower than generally concealed, especially if the pus in these layers is not in the original deposition site (Fig. S2). The last, the most[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–]are found in samples that do not have evidence of a macroscopic manure. For these reasons, we see the bouncer as a minor contribution to our Na+Cl–and NO3– the total amounts and exclude the feces in our calculations.
Closed system?. In the next section of this paper, our calculation of the number of organisms required for production, through urination, Cthe residue of Na. Cthe residue of Cl, i
it is based on the assumption that the humble geochemistry has acted as an enclosed sedimentation system; ie, did not get lost nor lost to Na+Cl–and NO3– postdepositionally. Our model calculations explicitly confirm that the dam in Aşıklı Höyüku was not a perfectly closed system of rainfall infiltration over the past 10,000 years. However, it should have been considerably less permeable than the vast majority of open spaces. Levels 2 and 3 covering the humus contain many plastered floors or other hardened work surfaces that would prevent or greatly reduce the rainfall overtaking. Indirect evidences of limited perchloration include very high quality of bone collagen preservation in Levels 2 and 3 used in paleo-DNA studies and 14C dating (17). The state of macroscopic organic conservation is even better in lower levels of level 4 and level 5 based on observations in the field.
Another potential disorder of the closed system is the loss of salt by rinsing through the base. This option faces lower[On[On[Na[Na+].[Cl[Cl[Cl[Cl–], i[NOT[NO[NE[NO3–], for approximately two orders of magnitude (average 111 ×) in natural alluvium and a sudden increase of soluble salts above the contact between aluvium and overhead archaeological layers. These patterns are consistent with modeling and observation of climatic conditions in the southwestern United States, similar to Aşıklı Höyük. The depths of rainfall in these conditions are mostly limited to the upper surfaces of 2 to 3 m of soil profile and fall rapidly below 4 m (29). In Aşıklı Höyüku, depths of 0 to 4 m drop almost entirely on Level 2, so we can expect a small modification of primary anthropogenic geochemical patterns in Levels 3 to 5 and lower post-precipitation drops and rinse. In addition, the values recorded in other studies show elemental concentrations in the fattening and natural areas (40) similar to those in Aşıklı Höyük. Ignoring potential closed system losses makes our estimates of required urine fluxes conservative (i.e., minimum). Physical erosion of the Aşıklı Höyük mound over the past ~10,000 years may seem like a violation of the closed system assumption, but erosion only introduces uncertainty in our estimates of total numbers of organisms, which relies on the assumption that the shape of the now partially eroded mound was originally circular.
Last, ammonia volatilization of nitrogenous compounds is probably a key process that would result in loss of total NO3− and thus an underestimation of urination rates. Some N-rich compounds are lost after urination due to the process of ammonia volatilization:
1) (NH2)2CO + 2H2O → (NH4)2CO3
2) (NH4)2CO3 + 2H+ → 2NH4+ + CO2 + H2ON
3) NH4+ + OH− → NH3 + H2ON
The higher proportion of nitrogen in liquid waste represents a combination of not only nitrate but also nitrite, urea, and uric acid concentrations. The amount lost depends on air temperature, percentage of soil moisture, soil porosity, plant uptake, relative humidity, and precipitation (46–50). Reynolds and Wolf (46) and Whitehead and Raistrick (50) both show an approximate loss of ~45% of urinary nitrogen in the form of ammonia under the climatic conditions of modern-day Turkey, which we adopt for our calculation of the corrected concentration of nitrate in urine (
Modeling of urination rates and Neolithic organisms
We can now turn to estimating the density (Dorg and) of organisms per square meter for each archaeological Level (5 to 2) and the total number of organisms (Norg and) for the entire tell, required to produce the calculated values of Cresidual Na. Cresidual Cl, i
, Calculation of soluble[Na[Na[Na[Na+].[Cl[Cl[Cl[Cl−], i[NO[NO[NO[NO3−]produced by a single human and/or caprine assumes averages (Curin and) for these ions in urine of both groups taken from the literature[([([([(31. 51–55) and see tables S3 to S5 for full references], sedimentation rate, runoff fraction, urination rate, and fraction of time spent on the mound. We can then estimate the population density (Dorg and, in organisms per square meter) necessary to produce Costatak and
(5)where α is the unitless runoff ratio, INR is the urination rate (in liters per year), Γ is the sedimentation rate (in meters per year) (8), and Curin and is the concentration of the salt species in the organism’s urine in moles per liter (tables S3 to S5). The sedimentation rate is determined in two different ways: (i) using a constant sedimentation rate throughout the entire mound and (ii) using dated level boundaries to define a sedimentation rate for each archaeological level[seetablesS3toS5forvaluesand([seetablesS3toS5forvaluesand([seetablesS3toS5forvaluesand([seetablesS3toS5forvaluesand(8) for dates and explanations], Equation 5 yields estimates of increasing organism densities upward through the tell (Fig. 6, A and B, and tables S3 to S5), using both variable and constant sedimentation rates. Natural alluvium and Level 5 have comparably low-average[Na[Na[Na[Na+].[Cl[Cl[Cl[Cl−], i[NO[NO[NO[NO3−](Fig. 4), suggesting that human/animal populations were initially very low, near background for preoccupation use of the area. Dorg Na estimates are also near background for Level 4, but Dorg Cl and
increased to ~0.01 to 0.025 organisms per square meter in Level 4, and all three salt-derived organism densities jumped sharply to ~0.05 to 0.10 organisms per square meter in Level 3 (Fig. 6, A and B). Level 2 densities are comparable, slightly higher (in the case of Dorg Na) or slightly lower (in the case of Dorg Cl and
) than Level 3. These estimates match closely with the changes in relative abundance of caprines in the vertebrate faunal assemblages averaged by level from Aşıklı Höyük (Fig. 6C) (7).
Last, we can use an average Costatak and (equal weighting of all four levels to avoid sampling biases) to calculate the average number of organisms that lived on the mound at any given moment over its ~1000-year duration by multiplying the produced average population density by the area (57,700 m2) of the tell
Equation 6 yields an estimate of, on average, 1790 ± 510 (1σ SD) organisms that lived and urinated on the mound per day for the ~1000-year duration of the occupation based on all three soluble salts of interest.
Since animal and human urine are geochemically indistinguishable, this estimate cannot distinguish between animals and humans living on the site. However, it is likely that only humans and caprines were dominant contributors of urine to the mound deposits. Small rodents invaded the settlement in small numbers in all periods based on the presence of their skeletal remains (7) and coprolites (10). Postoccupation burrowing by other rodent species also occurred, mainly blind mole rats of the genus Spalax, but the low density of tunnels indicates that the number of resident animals would have been few. Dogs may have existed in this region and period, but traces of their presence are minimal or absent in the four levels.
PERSPECTIVE AND CONCLUSIONS
An important but intractable question for archaeologists who study the forager-producer economic transition concerns the scale of human investment in animal management and the pace of its increases with time. This study uses urine salt inputs as a metabolic scale of the intensity of caprine management practices at Aşıklı Höyük by tracking, in relative terms, the growth of the community and its animals with each succeeding archaeological level.
Previous archaeological work at Aşıklı Höyük has shown that caprines were held captive and managed in small numbers inside the settlement from level 5 onward and that caprine management developed into a key part of the economy over the course of one millennium. What has been lacking, however, is reliable information about the scale of increase in biological (metabolic) activity on the mound, which we treat as a partial proxy of changing economic investments by the human inhabitants. Because some caprines were hunted rather than managed, especially in the earlier periods, independent evidence of the scope of captivity can be gleaned from the urine inputs from humans and livestock combined. At Aşıklı Höyük, the urine inputs greatly outstrip architectural evidence of human population density in each layer, as loosely indicated by the number of residential buildings (a topic of ongoing study) (56).
Five key outcomes of our study concern changes in human behavior as quantified by our new methodological approach. First, there are 5 to 10× increase in[Na[Na[Na[Na+].[Cl[Cl[Cl[Cl−], i[NO[NO[NO[NO3−]from levels 5 to 4 and 10 to 1000× increase from levels 5 to 3 at Aşıklı Höyük (Fig. 4). Second, urine inputs decline somewhat from levels 3 to 2, when higher architectural density and other data suggest that animal corrals were shifted to the mound periphery or areas of the mound that have yet to be excavated. Third, there is a marked spatial variation in urine inputs by humans and livestock in each layer, observations supported by micromorphological analyses of dung and midden (57). Middens and some alleyways must have been used as toilets by the humans. Animal urine accumulated not only wherever livestock were penned but also where humans used midden and dung as a binder in plasters and, probably more significantly, around fireplaces where humans recycled dung into fuel. The fourth outcome of the study is proof that simple techniques for determining abundances of major elements and δ15N values allow for the identification of urine as the dominant soluble salt contributor. The last outcome, also methodological, is that our approach can potentially be used to provide quantitative clues for animal management and/or human occupation in areas where there is a lack of other physical evidence (i.e., bones, dung layers, and major architecture). The analysis of urine salts as indications of metabolic activity in sites is only feasible; however, if chemical preservation in sediments is very good, such as in thickly stratified arid land tells with dense architectural features and in dry caves.
Returning to the larger questions posed by this research, the urine salt data demonstrate large increases in the scope and intensity of livestock keeping at Aşıklı Höyük over a span of 1000 years. The results contribute to evidence of a local (endemic) evolution of management practices. Aşıklı Höyük is located well outside (west of) the Fertile Crescent area, once believed to be the exclusive heartland of Neolithic emergence. Results such as ours demonstrate the existence of a much broader, diffuse network of societies involved in domestication processes and the evolution of Neolithic lifeways in Southwest Asia. The urine salt data put a scale to the evolutionary process at Aşıklı Höyük and thus represent a unique contribution in domestication research. Future studies involving estimates of human populations across archaeological levels will aid in distinguishing animal and human contributions to the soluble salt in archaeological deposits.
We analyzed 113 samples to develop a comprehensive spatial and temporal view of the soluble salt chemistry of the tell and areas surrounding Aşıklı Höyük. Fresh exposures on the north (area 4GH), west (area 2JK or “west section”), and south (southern transect) sides of the tell allowed us to sample laterally over tens of meters and vertically from the natural alluvium (24 samples) underlying the mound up through the major archaeological levels (89 samples; Figs. 1 and 3). Within the archaeological layers, general midden (n = 53), dung-dominated midden (n = 9), brick, mortar, and plaster (n = 7), hearths (n = 11), and alleyways (n = 9) were sampled (table S1).
All samples were analyzed for their major element composition and δ15N values in the soluble salt fraction. To isolate the soluble salts, 5 to 20 g of each sample was passed through a 5-mm sieve to remove coarse charcoal and plant matter, bone, obsidian flakes, hackberry endocarps, and gravel. Samples were then heated in 20–40 ml of distilled water (Milli-Q) at 70°C for 24 hours. The supernatant was decanted and set aside for soluble salt elemental analysis. A separate portion of the supernatant was evaporated in a drying oven for 48 hours. The evaporated salt residues were used for nitrogen isotope analysis, and the results are expressed in the familiar per mil notation as δ15N =[([([([(Ruzorak/Rair) − 1]× 1000, where R = 15N/14N. Elemental analyses were conducted at the University of Arizona’s Laboratory for Emerging Contaminants housed in the Department of Soil, Water, and Environmental Science.
Anion concentrations were determined by ion chromatography on a Dionex ICS-1000 system with an anion exchange column (AG-22 + AS-22). Testing followed Method 4110 in Standard Methods for the Examination of Water and Wastewater, and the detection was completed using eluent conductivity and chemical suppression. Cations were analyzed using an Agilent 7700× ICP-MS (inductively coupled plasma mass spectrometry).
We calculated population means of[Na[Na[Na[Na+].[Cl[Cl[Cl[Cl−], i[NO[NO[NO[NO3−]in tell refuse to calculate population densities and numbers. Most of our sampling comes from middens, and the large sample size shows near log-normal to log-normal distributions (positive skew, due to the ~104 range in values), where the mean and median are different by ~2 to 20×, depending on the ion. Since it is likely that the larger salt concentrations are indicative of organism urination and that the lowest values are likely midden samples devoid of urine from humans and caprines and/or areas not involved with the corralling of animals, means (averages) are the optimal values to use for estimating organism populations through our mass balance model, as means favor higher values in positively skewed populations. In addition, for salt concentrations in wood ash, rainfall, construction debris, and urine, we adopted average values from the literature and/or our study, so our usage of means for midden samples follows this procedure. As a result, we also reported means for all sample types in Results. An alternative is to use population medians, which would statistically better represent the positively skewed populations ([NO[NO[NO[NO3−]). Use of medians generally yields ~2 to 4× lower paleo-organism estimates for Na+ and Cl− and up to ~20× for NO3− and shifts levels with currently (or close to) negative densities/populations farther negative. While this would not alter conclusions involving the relative changes in the scale of metabolic processes, it does introduce uncertainty in our absolute estimates. Tables S2 to S5 allow for the reader to better quantify changes in Costatak and. Dorg and, or Norg and using medians instead of means. Future application of our model, using self-determined salt concentrations of urine, rainfall, wood ash, etc. at the site may be improved by implementing medians for all components, especially if the sampled populations of the other salt contributors and urine are nonnormal.
Supplementary material for this article is available at http://advances.sciencemag.org/cgi/content/full/5/4/eaaw0038/DC1
Section S1. Density and constituent fraction determination for midden and construction debris
Section S2. Nitratine formation
Section S3. Wood ash ion concentrations and density
Section S4. Rainfall concentration and calculations
Section S5. Runoff fraction for rain
Section S6. Fraction of time spent on the site
Section S7. Ion concentrations in human and caprine urine
Section S8. Example calculation
Section S9. Calculation of sedimentation rates
Section S10. Heterogeneity of elemental concentrations across various samples
Section S11. Sensitivity of the mass balance model
Fig. S1. Infrared spectrum from a dung layer in midden (Level 3).
Fig. S2. Comparison of salt concentrations in various archaeological and nonarchaeological materials.
Fig. S3. Box and whisker plot of soluble salt concentrations (in moles × 1000 kg−1) across three sampling sections: area 4GH, area 2JK, and southern transect.
Fig. S4. Four pie diagrams displaying soluble salt percentages.
Table S1. Soluble salt chemistry and δ15Nsoluble of archaeological and nonarchaeological layers at Aşıklı Höyük.
Table S2. Statistical information of soluble salts based on material, spatial, and temporal setting.
Table S3. Mass balance and organism estimation model of sodium at Aşıklı Höyük.
Table S4. Mass balance and organism estimation model of chlorine at Aşıklı Höyük.
Table S5. Mass balance and organism estimation model of nitrate at Aşıklı Höyük.
Table S6. Density data from midden, construction material, and alluvium samples at Aşıklı Höyük.
This is an open-access article distributed under the terms of the Creative Commons Attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
REFERENCES AND NOTES
U. Esin, S. Harmankaya, Aşıklı, Neolithic in Turkey (Arkeoloji ve Sanat, 1999).
M. Özbaşaran, G. Duru, M. Uzdurum, Architecture of the early settlement and trends through the cultural sequence, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M. Özbaşaran, G. Duru, M. C. Stiner, Eds. (Ege Press, 2018), pp. 57–103.
J. Quade, M. C. Stiner, A. Copeland, A. E. Clark, M. Özbaşaran, Summary of carbon-14 dating of the cultural levels of Aşıklı Höyük, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M Özbaşaran, G Duru, M. C. Stiner, Eds. (Ege Press, 2018).
C. Kuzucuoğlu, J.-P. Dumoulin, S. Saulnier-Copard, Geomorphological and palaeoenvironmental setting of Aşıklı Höyük, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M. Özbaşaran, G. Duru, M. C. Stiner, Ed. (Ege Press, 2018).
M. Ergun, M. Tengberg, G. Willcox, C. Douché, Plants of Aşıklı Höyük and changes through time: First archaeobotanical results from the 2010–14 excavation seasons, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M. Özbaşaran, G. Duru, M. C. Stiner, (Ege Press, 2018), pp. 191–217.
G. Duru, “Human-space, community-settlement interactions during the end of the 9th and the beginning of the 7th Mill cal BC: Aşıklı and Akarçaytepe,” thesis, Istanbul University Prehistory Department (2013).
S. M. Mentzer, Micromorphological analyses of anthropogenic materials and insights into tell formation processes at Aşıklı Höyük, 2008–2012 field seasons, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M. Özbaşaran, G. Duru, M. C. Stiner, Eds. (Ege Press, 2018).
M. Özbaşaran, G. Duru, M. C. Stiner, The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin (Ege Press, 2018).
H. Buitenhuis, J. Peters, N. Pöllath, M. C. Stiner, N. D. Munro, Ö. Saritaş, The faunal remains from levels 3 and 2 of Aşıklı Hoyuk: Evidence for emerging management practices, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M. Özbaşaran, G. Duru, M. C. Stiner, Eds. (Ege Press, 2018).
J. Peters, F. Neuberger, I. Wiechmann, M. Zimmermann, M. Balasse, N. Pöllath, Shaping the sheep: Human management and decision-making at Aşıklı Höyük, Central Anatolia, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M. Özbaşaran, G. Duru, M. C. Stiner, Eds. (Ege Press, 2018).
G. Tsartsidou, The microscopic record of Aşıklı Höyük: Phytolith analysis of material from the 2012–2016 field seasons, in The Early Settlement of Aşıklı Höyük: Essays in Honor of Ufuk Esin, M. Özbaşaran, G. Duru, M. C. Stiner, Eds. (Ege Press, 2018).
A. H. Colak, I. D. Rotherham, A review of the forest vegetation of Turkey: Its status past and present and its future conservation, in Biology and Environment: Proceedings of the Royal Irish Academy (Royal Irish Academy, 2006), pp. 343–354.
E. K. Berner, R. A. Berner, The Global Water Cycle (Prentice-Hall, 1987), 397 pp.
Z. Sharp, Principles of Stable Isotope Geochemistry (Person/Prentice Hall, 2007), 344 pp.
H. Jönsson, A. R. Stintzing, B. Vinnerås, E. Salomon, Guidelines on the Use of Urine and Faeces in Crop Production (EcoSanRes Programme, 2004).
H. Jönsson, A. Baky, U. Jeppsson, D. Hellström, E. Kärrman, Composition of urine, feaces, greywater and biowaste for utilisation in the URWARE model, in Urban Water Report (Urban Water, Chalmers University of Technology, 2005), 6.
G. Duru, “Central Anatolian Neolithic Architecture,” thesis, Istanbul Technical University (2005).
M. L. Schumacher, “Biomolecular and micromorphological analyses of suspected fecal deposits at Neolithic Aşıklı Höyük, Turkey,” thesis, Eberhard-Karls-Universität Tübingen (2018).
F. Mees, T. V. Tursina, Salt minerals in saline soils and salt crusts, in Interpretation of Micromorphological Features of Soils and Regoliths, G. Stoops, V. Marcelino, F. Mees, Eds. (Elsevier, 2010), pp. 289–321.
P. F. Krause, K. L. Flood, “Weather and climate extremes” (no. TEC-0099, Army Topographic Engineering Center, 1997).
M. I. Budyko, Climate and Life (Academic Press, 1974).
C. A. Hastorf, Gender, space, and food in prehistory, in Engendering Archaeology: Women and Prehistory, J. M. Gero, M. W. Conkey, Eds. (Blackwell, 1991), pp 132–159.
M. Özbek, Aşıklı Höyük Neolitik Çağ İnsanları, in VIII. Arkeometri Sonuçları Toplantısı (Ankara Üniversitesi Basımevi Müdürlüğü, 1993), pp. 201–212.
A. C. Guyton, Textbook of Medical Physiology (W.B. Saunders Co., 1986).
L. P. Sullivan, J. J. Grantham, Physiology of the Kidney (Lea & Febiger, 1982).
M. Wolgast, Rena vatten. Om tankar i kretslopp. Crenom HB, Uppsala, in Human Excreta for Plant Production, H. Heinonen-Tanski, C. V. Christine van Wijk-Sijbesma, (Bioresource Technology, 1993), vol. 96, pp. 403–411.
Acknowledgments: We thank M. K. Amistadi for assistance in running element composition analyses, D. Dettman and Z. Zhang for assistance with δ15N analyses, colleagues and students at Istanbul University for research support at Aşıklı Höyük, M. Potthoff for assistance with sample preparation, A. Hudson for laboratory assistance and many useful discussions, M. Walvoord for discussion of nitrogen isotopes, L. McGuire and E. Morin for discussion of runoff coefficients, and M. Kohn and two anonymous reviewers for constructive review comments. Funding: This project was funded by an Archaeology Program grant from the NSF to M.C.S. (BCS-1354138). Author contributions: All authors designed and directed the study, including the sampling strategy and sample collection, contributed to interpretations of the data, and provided comments and revisions on the manuscript. S.M.M. provided preliminary datasets. J.T.A. and J.Q. performed experiments and developed the computational framework and mass balance model. J.T.A., J.Q. and M.C.S. wrote the manuscript. Competing interests: This manuscript and its contents have not been published and is not under consideration for publication elsewhere. All authors declare that they have no competing interests. Data and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the authors.
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