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Wild lentil and chickpea harvest in Israel: bearing on the origins of Near Eastern farming
Journal of Archaeological Science 35 (2008) 3172–3177
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Wild lentil and chickpea harvest in Israel: bearing on the origins of Near Eastern farming Shahal Abbo a, *, Inbar Zezak a, Efrat Schwartz a, Simcha Lev-Yadun b, Zohar Kerem a, Avi Gopher c a
The Levi Eshkol School of Agriculture, The Hebrew University of Jerusalem, Rehovot 76100, Israel Department of Biology Education, Faculty of Science and Science Education, University of Haifa-Oranim, Tivon 36006, Israel c Sonia and Marco Nadler Institute of Archaeology, Tel-Aviv University, Ramat Aviv 69978, Israel b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 23 January 2008 Received in revised form 24 June 2008 Accepted 6 July 2008
Several small seeded plants were domesticated as grain crops in the Near East and other domestication centers. In this study we investigate the potential of small seeded wild lentils, and chickpea as a food source for hunters-gatherers. The yield potential and the return in terms of grams of seeds per hour of collection time were evaluated in several wild populations in Israel. The yield figures never exceeded 50 g/h, and in most cases were below 20 g/h. These data reaffirm Ladizinsky’s claim that wild lentils are unlikely to have been a staple resource for hunter-gatherers prior to plant domestication. The result presented herein may be significant vis-a-vis the role attributed to small seeded (‘inefficient’) plants in the Broad Spectrum hypothesis concerning late Paleolithic, pre-agricultural societies. It may also contribute to a more careful interpretation of plant remains recovered from pre-agricultural sites. Ó 2008 Elsevier Ltd. All rights reserved.
Keywords: The Broad Spectrum Revolution Legumes domestication Neolithic Revolution Wild legumes harvest
1. Introduction Understanding the processes of plant domestication in the Near East could benefit from systematic harvesting exercises of the wild taxa that were adopted as crop plants and their close relatives in natural ecosystems. Population structure and the potential yield of wild stands are highly relevant here since from the very early attempts that eventually resulted in domestication, plant–human interaction was largely dependent upon the biological features of the species involved (e.g., Abbo et al., 2005, 2008, in press; Jackson, 1996; Ladizinsky, 1979, 1987; Rindos, 1984; Zohary, 2004). Both cereals and legumes were adopted as grain crops in prehistoric times in several ancient agricultural centers, e.g., maize and beans in Central America, sorghum and cowpea in Africa (Harlan, 1992). For the Near East, the adoption of legumes and cereals is referred to as a simultaneous process, hence the ‘‘crop assemblage’’ concept (Zohary and Hopf, 2000, p. 242). This ancient and highly successful combination of cereals and legumes is considered as a natural choice due to the complementary nutrient contents of the two crop types (Zohary and Hopf, 2000, p. 92). Studies of plant domestication included considerable work on archaeobotanical assemblages from archaeological sites in the region (see summaries in Garrard, 1999; Zohary and Hopf, 2000; Nesbitt, 2002; and references therein), some archeoethnobotanical observations (e.g., Hillman, 1984; Hillman and Davies, 1990; Simms and * Corresponding author. Tel.: þ972 8 9489443; fax: þ972 8 9489899. E-mail address: [email protected] (S. Abbo). 0305-4403/$ – see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.jas.2008.07.004
Russell, 1997), series of controlled experiments including sowing (see papers in Anderson, 1992, 1999), harvesting and threshing of package plants, use wear analysis on stone tools from the relevant sites in search of evidence for the respective activities on the unearthed tools (e.g., Anderson, 1998; Yamada, 2000) and controlled collection exercises of wild relevant plants, mainly cereals but recently legumes too (Abbo et al., 2008). Cereals were at the focus of much of this research, including controlled field collection of the wild taxa, for understandable reasons, mainly their major role in world economy to this very day. Worthy of note are the pioneering wild wheat harvest of Harlan (1967) in eastern Turkey, Ladizinsky’s (1975) wild cereals collection in the Jordan Valley and the recent work of Kislev et al. (2004). Unlike the above, legumes domestication was rarely discussed in the context of the ecological conditions of their progenitors and cost/benefit considerations concerning their collection for the simple reason that until recently, no controlled wild legume collection data were available (Abbo et al., 2008). Several years ago we initiated a project aiming at better understanding Near Eastern grain legumes domestication. In this framework we studied domestication syndrome traits (Abbo et al., 2002), ancient agrotechnology (Abbo et al., 2003) and nutritional quality (Kerem et al., 2007) in chickpea. Our wild pea harvest was part of this effort (Abbo et al., 2008). Here we report and discuss controlled field collections of lentil and chickpea taxa. The goal of this work is to provide yield data from experimental harvests of two wild lentil species (Lens orientalis (Boiss.) Handel-Mazzeti and Lens odemensis Ladiz.) and one wild small seeded chickpea species (Cicer judaicum Boiss.) as a reference.
S. Abbo et al. / Journal of Archaeological Science 35 (2008) 3172–3177
Mean seed weight of wild lentil is mere 0.01 g or less (Ladizinsky, 1987). Thus far, the available data on wild lentil yield concern only mean number of seeds per plant (Ladizinsky, 1987) but no mean yield per time unit per collector. As to wild lentil collections conducted by the late C. Sperling in eastern Turkey, apparently the results were disappointing (in terms of the grain yield) and were not published (Gideon Ladizinsky, 2007, personal communication). Based on the mean number of lentil seeds per plant and their small mean seed weight, Ladizinsky (1987) concluded that wild lentils could not have been a staple food in pre-agricultural times. L. orientalis is the presumed wild progenitor of domesticated lentil (Ladizinsky, 1999), therefore its yield potential in the wild is highly relevant for the domestication issue, while L. odemensis is a closely related species with a similar seed size that was never domesticated. C. judaicum was chosen as a reference species since its seed size is similar to that of the two above lentil taxa (ca. 0.01 g/seed for Lens sp. and 0.02 g/seed for C. judaicum), its ecological affinities are quite similar to those of the two lentil species, but it was never domesticated. It is worth noting that the wild progenitor of domesticated chickpea (C. reticulatum Ladiz.) known only from southeastern Turkey has much larger seeds, ca. 0.11–0.15 g/seed, similar to the three Near Eastern wild pea taxa (ca. 0.1 g). The results of wild legumes experimental harvest may promote the discussion of the incentives underlying the ancient human choice that led to specific crop domestication. While engaged in the collection, and seed cleaning of these small seeded chickpea and lentils we thought that the obtained data are also relevant for the discussion concerning the use of small grain (SG) plants and their role in the origin of agriculture. The great efforts invested to obtain significant amounts of such SGs, and the presumed role of such ‘‘small seeded resources’’ (Weiss et al., 2004a) were recently interpreted as evidence for broadening the dietary base of preNeolithic communities (Weiss et al., 2004a,b). We think that the picture emerging from our collection exercises enables to further discuss this issue on a more solid ground.
laboratory, each pod was opened, and all mature seeds recovered from each bag weighed. 3. Results The harvest results of the 2006 season (Tables 1 and 3) are based on the average seed yield (g) per plant obtained from the sampled plants, multiplied by the number of observed target plants per run. For the 2007 season, the results (Tables 2 and 4) are in terms of the actual grain yield (g) obtained by each collector during each run (20 or 40 min, while collecting all observed target plants), as well as the calculated return per hour of harvest time. We did not take into account the time of separating the seeds from other plant material, i.e., pods and straw. 3.1. Wild lentil L. orientalis is a short stature plant, rarely exceeding 15 cm height in nature (Fig. 1). It occurs from Turkey to Tadjikistan and from the Crimea to Israel as an element of primary habitats in open or partly shaded formations on shallow/stony soils at altitudes ranging from 500 to 1700 m, and where it is not subject to competition by aggressive cereals or other herbaceous species (for more details on the ecology see, Ladizinsky, 1993). Lens odemensis is also a short stature plant, rarely exceeding 15 cm height with affinity to primary stony and rocky habitats. In Israel it occurs only on soils derived from basaltic bedrock while in Turkey it is known Table 1 Harvest data of wild lentil in northern Israel during the 2006 season Species and sites
Date
Collector and time (min)
No. of plants
Mean yield per plant (g)
Calculated yield (g/h)
L. odemensis Tel Abu-Khanzir
18.5.06
A 50 C 33 E 30 G 50 H 50 I 50 D 50
215 31 4 47 183 105 0
0.1 0.1 0.1 0.1 0.1 0.1 –
25.8 5.6 0.8 5.6 21.9 12.6 0
28.5.06
A 20 A 20 B 20 B 20
72 33 60 30
0.03a 0.01a 0.03a 0a
Tel BaneiGhassan
18.5.06
E 30 C 45 G 45 D 30 H 40
5 88 64 80 40
0.1 0.1 0.1 0.1 0.1
1 11.7 8.5 16 6
Masa’ade forest
19.5.06
A 20 D þ I 20
19 0
–
5.7 0
A 40 C 40 D 40 E 40 G 40 H 40 I 40
54 98 40 96 37 8 0
0.1 0.1 0.1 0.1 0.1 0.1 –
8.1 14.7 6 14.4 5.5 1.2 0
A 40 B 40
16 25
0.07 0.4
2. Materials and methods 2.1. Wild Lens and Cicer harvest Wild Lens and Cicer were harvested in several sites in the Mediterranean district of Israel during the seasons of 2006 and 2007 (Supplementary figure 1). The chosen sites and their physical characteristics are listed in Supplementary table 1. These sites represent the typical plant formations in which the richest populations of wild lentils and wild chickpea occur in Israel. Special efforts were made to select sites free of grazing and protected from current human interference. Activity within nature reserves was conducted under a special license from the Israeli Park & Nature Reserve Authority. Collectors were assigned to a certain area in each site. Each collector was equipped with paper bags and a stopper watch to monitor harvest time. In most sites each collector conducted 2–3 runs, 20–40 min each, placing the collected material of each run into a separate marked bag. In the first year (2006) the collectors counted the number of target plants they encountered while moving in the landscape and sampled random whole ripe plants (between 1 and 23). These sampled plants were threshed by hand over trays in the lab, and their ripened seeds weighed, to allow a calculation of the potential yield per time unit per collector. In the second season (2007) collectors pulled all the target plants they encountered, and placed the whole harvested individuals in marked bags. Following the harvest, paper bags were placed in an oven at 48 C for 3–4 days to dry. The plant material in each bag was carefully separated over trays in the
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L. orientalis Hermon 1
Hermon 1
18.5.06
6.8 0.99 5.4 0
1.68 3.75
Harvesters’ identity: A- Inbar Zezak, B- Efrat Schwartz, C- Shahal Abbo, D- Roi Barak, E- Avi Gopher, G- Mickey Frenkel, H- Ariela Sharvet, I- Alona Rivlin, K – Yigal Aviv, L – Elinor Ben Hanan. a Most plants were completely dry and their pods open.
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Table 2 Harvest data of wild lentil in Israel, spring 2007 Species and Site
L. odemensis Tel Abu-Khanzir
Masade Forest
L. orientalis Mt. Hermon (gate)
Collection date
Collectora and time (min)
8.5.07
A 20 K 20
1.74 2.38
C 20 A 20
1.41 1.77
C 20 E 20 A 40 A 20
5.53b 12.42 1.96b 4.21
3.085
16.59 37.26 2.94 12.63
E 20 C 20 A 20
1.61 0.71 2.37
1.16 2.37c
4.83 2.13 7.11
E 20 C 20 A 20
7.71 14.86b 2.8
11.285 2.8c
23.13 44.58 8.4
10.5.07
21.5.07 28.5.07
Mt. Hermon 1
21.5.07 28.5.07
Mt. Hermon 2
Table 4 Harvest data of C. judaicum in Israel, spring 2007
21.5.07 28.5.07
Actual yield (g)
Mean yield per exercise (g)
Calculated potential (g/h)
2.06
5.22 7.14
1.59
4.23 5.31
8.975
a
For harvesters’ identity, see legend of Table 1. In addition to lentils 0.38, 0.06, 0.46 g, respectively, of Lathyrus aphaca seeds were taken into the collection bags. c No statistics, single go. b
from both basaltic and calcareous regions (Ladizinsky, 1993). In most parts of their natural distribution range, populations of these species occur in patches and are often pretty thin comprising of only few individuals, however, the locations chosen for the experimental harvest support massive populations with relatively rich
Table 3 Harvest data of wild Cicer judaicum during the 2006 season in several sites, Israel Site
Date
Collectora and time (min)
No. of plants
Mean pods per plant
Calculated maximal yield per plant (g)b
Shilat Forest
18.4.06
E 20 E 20 E 20 A 20 A 20 A 20 D 20 D 20 D 20
4 12 0 14 1 4 15 4 5
23.25 8.42
0.47 0.17
5.64 6.12
2.79 3 3 2.47 4.25 5.80
0.05 0.05 0.06 0.05 0.08 0.12
2.35 0.15 0.72 2.22 1.02 1.74
E 20 E 20 E 20 A 20 A 20 A 20 D 20 D 20 D 20
9 0 5 7 3 4 7 0 8
2.67
0.04
1.17
6 5.29 6 8.75 2.43
0.12 1.1 0.12 0.18 0.05
1.8 2.2 1.1 2.1 1.02
3
0.06
1.44
Modiin
18.4.06
Calculated yield (g/h)
Modiin
21.4.06
C 30 E 45
55 37
8.8 3.68
0.18 0.07
19.36 3.45
Shoham 2
28.4.06
E 20
32
2.28
0.05
4.8
Shoham 3
28.4.06
E 20 E 20 E 20
24 24 9
3.21 1.83 5.22
0.06 0.04 0.10
4.6 2.88 2.81
a
For harvesters’ identity, see legend of Table 1. The calculation was based on seed weight of 0.02 g and mean number of one seed per pod. b
Site
Collection date
Collectora and time (min)
Actual yield (g)
Modii’n 1
27.4.07
A 20 I 20 H 20 L 20
1.27 0.86 0.42 0.19
A 30 I 30 H 30 L 30
1.05 0 2.29 0.01
A 20 I 20 H 20 L 20
2.21 3.32 1.04 0.7
A 20 I 20 H 20 L 20
1.02 0.89 0.11 0.86
A 20 I 20 H 20 L 20 A 20 I 20 H 20 L 20
0.92 0.71 0 0.74 1.98 0.47 1.49 1.82
C 20 C 25 C 20 E 20 E 20 E 20
2.41 6.12 6.73 0.09 0.86 2.19
Modii’n 2
Modii’n 3
Shilat Forest 1
Shilat Forest 2
Mevo – Horon
27.4.07
27.4.07
27.4.07
27.4.07
4.5.07
Mean yield per exercise (g)
Calculated yield per hour (g/h)
0.68
3.83b 2.58 1.26 0.58
0.83
2.1 0 4.58 0.02
1.82
6.63 9.96 3.12 2.1
0.72
3.06 2.67 0.33 2.58
1.01
2.76 2.13 0 2.22b 5.94b 1.41 4.47 5.46
3.06
7.23 14.69 20.19 0.27 2.58 6.57
a
For harvesters’ identity, see legend of Table 1. b In addition (to chickpea), 0.73, 0.37 and 0.1 g, respectively, of P. fulvum seeds were collected.
stands. Even in such ‘‘rich’’ wild lentil habitats, there is a great difficulty to harvest large amounts due to the distribution pattern of the plants. An illustration for this is given in Supplementary figure 2, with the frequency distribution of L. odemensis plants spotted on 30 cm to each side of a measuring tape along a 30 m transect in Tel Banei-Ghassan, northern Golan (see Supplementary figure 1). The grain yields from collections conducted during the 2006 season were highly variable (Table 1). The number of plants observed by the individual collectors varied between 0 and 215, demonstrating the irregular distribution of the species in the studied habitats. This wide variation in plant density was typical for the two species in all sites. The grain yield of L. odemensis, ranged between 0 and 25.8 g/h while that of L. orientalis never exceeded 15 g/h in 2006. It should be noted that in 20 out of 27 total runs of lentil harvest (two species), the calculated yield per hour was below 10 g (Table 1). The yield figures for the collection season of 2007 are pretty similar to the previous year (Table 2). Grain yields ranged between 2.13 and 37.26 g/h. The maximal yield obtained in 2007 was in L. orientalis. Similar to the situation in 2006, in nine out of 14 total harvest runs, the calculated yield was below 10 g/h (Table 2). In 2007 we collected all the observed target plants while moving across the site. Because lentil plants usually grow in mix stands with other creeping legumes such as Lathyrus, Vicia, Medicago, and Trifolium spp. among others, it often happened that non-target plants were taken into the collection bags (Table 2 and discussion below).
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In the 2006 season, the number of Cicer plants observed by the collectors varied between 0 and 55 (Table 3). The mean number of pods per sampled plant was also highly variable and ranged from either 1 or 0 to more than 20. Consequently the calculated grain yield ranged from close to 0 to nearly 20 g/h (Table 3). Similar to the 2006 results, the actual grain yields obtained during the 2007 season ranged between 0 and 6.7 g with a maximum of nearly 20 g/h (Table 4). 4. Discussion
Fig. 1. A typical wild lentil (Lens orientalis) plant with green and ripened pods.
3.2. Wild chickpea C. judaicum is a short stature plant mostly confined to stony and rocky niches where competition with more aggressive annuals is small (Fig. 2). Unlike the above wild lentils that form massive stands in parts of their range, C. judaicum has a patchy distribution pattern at all levels, from local niche to the region and beyond (for more details on its ecology see, Ben David et al., 2006). The locations chosen for the experimental harvest support the richest populations known to us based on an 8 years survey across the distribution of this species in Israel and Jordan (Ben David et al., 2006; Abbo, unpublished data).
This report describing controlled field harvests of wild lentil and chickpea in 2006 and 2007 relies also on our long-term experience with many of the areas and plant populations studied. Our field work during the past 8 years indicates that while some lentil populations are rich (with hundreds of plants easily found in less than an hour), wild chickpea populations are always small and highly patchy. Most of the collection sites were harvested in both seasons, e.g., Shilat Forest, Tel Abu-Khanzir, Mt. Hermon 1 while some were visited in one season only, e.g., Mt. Hermon (gate, 2) and Modiin 3 in 2007, or Tel Banei-Ghassan in 2006. In the past 8 years we have observed high variability in plant establishment from year-to-year. This phenomenon of erratic year-to-year establishment is a known characteristic of wild lentils (G. Ladizinsky’s unpublished field diaries). Therefore we cannot deduce on the effect of the first year collection on the plant stand in the second year. We assume that at the beginning of our study the seed bank in all of the sites was in equilibrium, and that the year-to-year yield variability seen in some of our stations is not a direct result of our preceding harvest. The grain yield results of our experimental harvests certainly support the idea that low yielding small seeded legumes such as wild lentils as well as small seeded chickpea were not a substantial food (staple) resource in hunter-gatherer subsistence economy. This idea was first put forward by Ladizinsky (1987) to support his model suggesting that a mutation for free germination had to establish itself in wild lentil populations prior to domestication (pre-adaptation for domestication). Indeed, the erratic year-to-year germination combined with the low yield potential of lentil makes it difficult to understand why wild L. orientalis was adopted as a crop plant in the first place. A similar suggestion was recently made concerning wild pea yield, based on the fact that among the three wild pea species native to Israel, the one adopted for domestication is the least productive (Abbo et al., 2008). The relatively low productivity of some of the wild progenitors of the Near Eastern grain legumes is in sharp contrast to grain yields obtained from the massive wild wheat and barley stands typical of the oak–pistachio park forest belt of the eastern Mediterranean (Harlan and Zohary, 1966), which allow to harvest from 200 g to more than 1 kg of grain per hour (appendix of Abbo et al., 2008; Harlan, 1967; Kislev et al., 2004; Ladizinsky, 1975). Several questions emerge from the data and the insights of our study: Why bother with wild plants that cannot provide even 100 g of seeds per hour of collection? Or in a more general way, why bother with small seeded plants at all? And more specifically, why did Neolithic people opt to adopt one specific small seeded lentil out of several available wild lentil species? Why was L. orientalis and not other Lens sp. with a similar potential taken for domestication? There may be two major lines of explanation: [i] That the small seeded legume species, in general, had some advantages (and possibly more so, the chosen ones). [ii] That there were (stressful?) conditions that pushed people to exploit these ‘inefficient’ species.
Fig. 2. A typical wild chickpea (Cicer judaicum) plant with green pods. For scale, pen length is 13 cm.
The first explanation relies on an earlier study on chickpea domestication that indicated a significant increase in the
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concentration of the essential amino acid tryptophan in the domesticated stock (Kerem et al., 2007) and its many advantages for Neolithic people. The grain yield results of a recent study on wild pea harvest also stress the possible role of seed composition and nutritional value (Abbo et al., 2008). We assumed that pea (Abbo et al., 2008), and we assume here that possibly lentil as well, if available in an appreciable amount may have provided certain nutritional benefits. Another possible advantage of collecting and later domesticating these legumes is especially important in the context of combining several food sources based on cultural traditions gained through a long adaptive process (e.g., Jackson, 1996). Prehistoric people may have developed a taste for lentil (or pea) upon gathering from the wild, but our yield data for pea (Abbo et al., 2008) and for lentil and chickpea (herein) indicate that this must have been a seasonal rare occasion. To satisfy the desire for pea/lentil soup – or any other food prepared from these plants – on a regular basis, one had to grow plots of pea or lentils. If we accept the importance of lentils for the diet, this can be seen as an incentive for domestication. We stress the relative importance of grain legumes based on the observation that wild cereals’ seeds are an easy-to-obtain and relatively stable resource while wild legumes populations are unreliable and difficult to exploit (Abbo et al., 2008; Ladizinsky, 1987). Another interesting feature worthy of note is that while chickpea shows ‘improved’ nutritional aspects after domestication (e.g., more tryptophan), emmer wheat domestication for example involved an appreciable reduction in seed protein (Avivi, 1978; Uauy et al., 2006). This may provide yet another clue to the importance and the possible role of grain legumes protein in the diet of early agricultural communities. So, collecting and later domesticating legumes to make them an important dietary staple may have provided some basic needs. Discussing the second, stress-related explanation would eventually require a deeper look at the Broad Spectrum Revolution (BSR) issue. While an in-depth discussion of the BSR hypothesis as presented by Flannery (1969) and its implications for the study of the origin of agriculture are beyond our scope, we wish to address a certain aspect of the subject following some published ideas based on archaeobotanical finds (Weiss et al., 2004a,b). The studies by Weiss et al. (2004a,b) are unique attempts to test the BSR hypothesis using botanical finds. In doing so, Weiss et al. (2004a,b) presented and discussed their remarkable archaeobotanical data from Ohalo II, a 23,000 years old site in Israel. They analyzed >90,000 plant remains and classified some 142 different taxa. Some 16,000 remains were small seeded cereals grains – Small Grain Grasses (SGG). To quantify the contribution of SGGs to the total plant food mass, Weiss et al. (2004b) calculated the volume ratio between the SGGs and the large seeded wild cereals (wheat and barley), concluding that SGGs constitute 34.6% of the total grain volume. Hence, they see these SGG (cereals) grains as staple food, first because of the large number of seeds found, and the fact that the seeds were fully mature; and second by noting the fact that these were found in a brush hut next to a grinding stone – that is, in a domestic consumption context (see also Weiss et al., 2008). They also use ethnographic analogies and evidence collected among hunters-gatherers and present-day traditional agriculturalists in support of their interpretation. They claim that the small grain size of these SGGs makes them very costly and difficult to collect because of their low stature and the high labor requirement for dehusking as compared with the seeds of large seeded cereals. The volume-based calculation is acceptable since a tight linear relationship between grain volume and weight exists in wheat (Millet and Pinthus, 1984). Based on a scatter diagram of more than 160 wheat samples (Millet and Pinthus, 1984), this relationship could be depicted as follows: weight in mg ¼ 1.1 þ1.34 (volume in mL). The histogram presented by Weiss et al. (2004b) considers
the volume of most of the SGG to be around 2 mL. So, according to the equation above: 1.1 þ1.34 2 ¼ 3.78 mg per single SGG; and thus 16,168 SGG seeds 3.78 mg ¼ 61,115 mg, or 61.1 g. If we follow the same calculation for the wheat–barley assemblage, then: 1.1 þ1.34 45 mL ¼ 61.4 mg per grain; and thus 2605 grains 61.4 ¼ 159,947 mg or 159.9 g. So according to the calculated weight fractions, SGGs made 27.6% of the total cereals remains in Ohalo II, which is quite close to the 34.6% volume fraction (Weiss et al., 2004b). Just before we discuss these data, we would like to highlight an observation we made during field work that might be of significance. In a few instances we obtained some non-target seeds while collecting lentil plants (Table 2). This happened because in natural habitats lentil plants grow intermingled with many other plant taxa (see Section 2). Despite strict instructions to the collectors and effort to focus only on the target species, in one case 0.38 g of Lathyrus seeds were collected alongside 5.53 g of lentil seeds, in the second case 0.06 g of Lathyrus seeds were collected with 1.96 g of lentil seeds and in the third case 0.46 g of Lathyrus seeds were found in the bag that contained 14.86 g of lentil seeds. The fraction of the Lathyrus seeds in the original samples (lentil þ Lathyrus) was 6.4%, 2.9% and 3% for the three above cases, respectively. This finding allows a rare opportunity to assess claims on the role of different small seeded sources in the ancient diet. For the sake of the discussion we assume that 80% of the target food species (e.g., lentil in our case), seeds are retained and later consumed and therefore will not be preserved on-site, while a similar fraction of the non-target (Lathyrus in our case) is rejected while cleaning the harvested plant material and hence is more likely to be found on-site if preserved. Applying the above 80% rejection vs. retention rates [namely, that 80% of the lentil seeds are consumed and 80% of the Lathyrus seeds are not consumed] to our harvest figures results in significant ‘enrichment’ for the non-target species from a mere 6.4 to 21%, from 2.9 to 10% and from 3 to 11% (more than threefold increase in all cases). Note the 27.6% SGG remains out of the total Ohalo II cereals calculated following Weiss et al. (2004b). We have no safe way to estimate the extent of yield contamination with non-target species in prehistoric time in general or in the case of Ohalo II in particular, because we have no information on the ancient harvest methods. Moreover, we cannot estimate the contribution of vegetal material used for adobe walls, or for hut roofs to the archaeobotanical finds. In fact, in the case of Ohalo II, Nadel et al. (2004) report on SGG grasses found in the same sort of huts used as bedding for sleeping areas including the very same species later mentioned as SGG staple food (Weiss et al., 2004a,b). The above discussion calls for a reconsideration of the attitude to plant remains in prehistoric sites, and extends beyond Weiss et al. (2004a,b). Is there a direct relationship between the composition of plant remains found in archaeological sites and the role of the different species in the diet? For example, is the assumption that major plant remains found on-site represent the ancient diet valid (Savard et al., 2007, p. 182)? Is it right to actually consider any amount of small seeded plants as staple food sources without questioning, especially when relating to the Neolithic Revolution? Are there biases caused by formation processes of the sites and human behavior relating to aspects other than food? As long as plant remains found on-site appear in minute quantities, like in the case of the single Cicer seed found in the Mousterian (60–50,000 YBP) Kebara Cave (Lev et al., 2005) and given the meager grain yield obtained in our experimental harvests as well as the possible effect of contamination while collecting, the definitions of such remains as ‘‘food remains’’ (let alone ‘‘staples’’) is not acceptable. In cases of larger numbers of botanical remains, like the case of Ohalo II (Weiss et al., 2004a,b), the question becomes worthy of an in-depth look. We are not given data
S. Abbo et al. / Journal of Archaeological Science 35 (2008) 3172–3177
concerning the distribution of these SGG taxa in the region around Ohalo II, nor on the potential of such wild stands in terms of grain yield per collection time unit to support the hypothesis regarding their staple role in the diet of the Ohalo II inhabitants. If we consider the grain yields obtained for small seeded legumes in our controlled collections (herein); and the possibility that some of the plant remains recovered from archaeological excavations do not directly reflect the target food species (‘shopping’) list of the food gatherers; and if we consider the possibility of other sources of botanical finds beyond food remains (like construction and bedding materials as in the case of Ohalo II, Nadel et al., 2004); and, in light of the possible bias in favor of non-target plants resulting from human behavior and the specifics of the depositional (site formation) processes; and, based on some of the above calculation concerning the weight of the collected SGG; we may cautiously say that SGGs cannot comfortably and easily be seen as staple foods even in cases when the assemblage is large, well analyzed and species-rich like that of Ohalo II. Our study points out the importance of controlled, experimental field harvests both for better understanding the natural setting of these plants and finding out the practicalities of their exploitation. Our data also contribute to a better understanding of the archaeobotanical record and its formation processes. Furthermore, it sheds light on the considerations leading to the choices people made in the past, and this in turn improves our understanding of the mechanisms and motivations behind plant domestication. 5. Note added in proof A recent report by Melamed et al. (2008) claims that the toxic Vicia peregrina was a cultivated crop in its own right for human food. However, applying our 80% rejection (for non-target species); 80% consumption (for target species) rates to the numbers provided by Melamed et al. (2008) results in the V. peregrina seeds making 28% of the lentilþVicia seeds. Note the 27.6% SGG fraction of Weiss et al. (2004b) in our discussion (above) which casts doubt on the presumed dietary role of the V. peregrina seeds Melamed, Y., Plitman, U., Kislev, M.E., 2008. Vicia peregrina: an edible early Neolithic legume. Vegetation History and Archaeobotany. doi:10.1007/s00334-008-0166-6. Acknowledgements SA and AG thank the Israel Science Foundation for financial support (Bikoorah grant no. 1406/05). We thank Prof. Gideon Ladizinsky for many years of fruitful interaction and learning. Appendix. Supplementary data Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j.jas.2008.07.004 References Abbo, S., Lev-Yadun, S., Galwey, N., 2002. Vernalization response of wild chickpea. New Phytologist 154, 695–701. Abbo, S., Shtienberg, D., Lichtenzveig, J., Lev-Yadun, S., Gopher, A., 2003. Chickpea, summer cropping, and a new model for pulse domestication in the ancient Near-East. Quarterly Review of Biology 78, 435–448. Abbo, S., Lev-Yadun, S., Rubin, B., Gopher, A., 2005. On the origin of Near Eastern founder crops and the ‘dump-heap hypothesis’. Genetic Resources and Crop Evolution 52, 491–495. Abbo, S., Zezak, I., Schwartz, E., Lev-Yadun, S., Gopher, A., 2008. Experimental harvesting of wild peas in Israel: implications for the origins of Near East farming. Journal of Archaeological Science 35, 922–929. Abbo, S., Saranga, Y., Peleg, Z., Lev-Yadun, S., Kerem, Z., Gopher, A. Reconsidering domestication of legumes vs. cereals in the ancient Near East. Quarterly Review of Biology, in press.
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Origins and ecological effects of early domestication in Iran and the Near East. In: Ucko, P.J., Dimbleby, G.W. (Eds.), The Domestication and Exploitation of Plants and Animals. Duckworth, London, pp. 73–100. Garrard, A., 1999. Charting the emergence of cereal and pulse domestication in south-west Asia. Environmental Archaeology 4, 67–86. Harlan, J.R., 1967. A wild wheat harvest in Turkey. Archaeology 20, 197–201. Harlan, J.R., 1992. Crops and Man, second ed. American Society of Agronomy and Crop Science Society of America, Madison. Harlan, J.R., Zohary, D., 1966. Distribution of wild wheats and barley. Science 153, 1074–1080. Hillman, G., 1984. Interpretation of archaeological plant remains: the application of ethnographic models from Turkey. In: van Zeist, W., Casparie, W. (Eds.), Plants and Ancient Man. A.A. Balkema, Rotterdam, pp. 1–41. Hillman, G.C., Davies, M.S., 1990. Measured domestication rates in wild wheats and barley under primitive cultivation, and their archaeological implications. Journal of World Prehistory 4, 157–222. Jackson, F., 1996. The coevolutionary relationship of humans and domesticated plants. Yearbook Physical Anthropology 39, 161–176. Kerem, Z., Gopher, A., Lev-Yadun, S., Weinberg, P., Abbo, S., 2007. Chickpea domestication in the Neolithic Levant through the nutritional perspective. Journal of Archaeological Science 34, 1289–1293. Kislev, M.E., Weiss, E., Hartmann, A., 2004. Impetus for sowing and the beginning of agriculture: ground collecting of wild cereals. Proceedings of the National Academy of Sciences of the United States of America 101, 2692–2695. Ladizinsky, G., 1975. Collection of wild cereals in the upper Jordan Valley. Economic Botany 29, 264–267. Ladizinsky, G., 1979. Seed dispersal in relation to the domestication of Middle East legumes. Economic Botany 33, 284–289. Ladizinsky, G., 1987. Pulse domestication before cultivation. Economic Botany 41, 60–65. Ladizinsky, G., 1993. Wild lentils. Critical Reviews in Plant Sciences 12, 169–184. Ladizinsky, G., 1999. Identification of the lentil’s wild genetic stock. Genetic Resources and Crop Evolution 46, 115–118. Lev, E., Kislev, M.E., Bar-Yosef, O., 2005. Mousterian vegetal food in Kebara Cave, Mt. Carmel. Journal of Archaeological Science 32, 475–484. Millet, E., Pinthus, M.J., 1984. The association between grain volume and grain weight in wheat. Journal of Cereal Science 2, 31–35. Nadel, D., Weiss, E., Simchoni, O., Tsatskin, A., Danin, A., Kislev, M., 2004. Stone Age hut in Israel yields world’s oldest evidence of bedding. Proceedings of the National Academy of Sciences of the United States of America 101, 6821–6826. Nesbitt, M., 2002. When and where did domesticated cereals firs occur in southwest Asia? In: Cappers, R., Bottema, S. (Eds.), The Dawn of Farming in the Near East. Studies in Early Near Eastern Production, Subsistence and Environment, ex-oriente, pp. 113–132. Berlin. Rindos, D., 1984. The Origin of Agriculture: an Evolutionary Perspective. Academic Press, New York. Savard, M., Nesbitt, M., Jones, M.K., 2007. The role of wild grasses in subsistence and sedentism: new evidence from the northern Fertile Crescent. World Archaeology 38, 179–196. Simms, R.S., Russell, K.W., 1997. Bedouin hand harvesting of wheat and barley: implications for early cultivation in southwestern Asia. Current Anthropology 38, 696–702. Uauy, C., Distelfeld, A., Fahima, T., Blechl, A., Dubcovsky, J., 2006. A NAC gene regulating senescence improves grain protein, zinc, and iron content in wheat. Science 314, 1298–1301. Weiss, E., Kislev, M.E., Simchoni, O., Nadel, D., 2004a. Small-grained wild grasses as staple food at the 23,000-year-old site of Ohalo II. Israel. Economic Botany 58, S125–S134. Weiss, E., Wetterstorm, W., Nadel, D., Bar-Yosef, O., 2004b. 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Contents lists available at ScienceDirect
Journal of Archaeological Science journal homepage: http://www.elsevier.com/locate/jas
Wild lentil and chickpea harvest in Israel: bearing on the origins of Near Eastern farming Shahal Abbo a, *, Inbar Zezak a, Efrat Schwartz a, Simcha Lev-Yadun b, Zohar Kerem a, Avi Gopher c a
The Levi Eshkol School of Agriculture, The Hebrew University of Jerusalem, Rehovot 76100, Israel Department of Biology Education, Faculty of Science and Science Education, University of Haifa-Oranim, Tivon 36006, Israel c Sonia and Marco Nadler Institute of Archaeology, Tel-Aviv University, Ramat Aviv 69978, Israel b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 23 January 2008 Received in revised form 24 June 2008 Accepted 6 July 2008
Several small seeded plants were domesticated as grain crops in the Near East and other domestication centers. In this study we investigate the potential of small seeded wild lentils, and chickpea as a food source for hunters-gatherers. The yield potential and the return in terms of grams of seeds per hour of collection time were evaluated in several wild populations in Israel. The yield figures never exceeded 50 g/h, and in most cases were below 20 g/h. These data reaffirm Ladizinsky’s claim that wild lentils are unlikely to have been a staple resource for hunter-gatherers prior to plant domestication. The result presented herein may be significant vis-a-vis the role attributed to small seeded (‘inefficient’) plants in the Broad Spectrum hypothesis concerning late Paleolithic, pre-agricultural societies. It may also contribute to a more careful interpretation of plant remains recovered from pre-agricultural sites. Ó 2008 Elsevier Ltd. All rights reserved.
Keywords: The Broad Spectrum Revolution Legumes domestication Neolithic Revolution Wild legumes harvest
1. Introduction Understanding the processes of plant domestication in the Near East could benefit from systematic harvesting exercises of the wild taxa that were adopted as crop plants and their close relatives in natural ecosystems. Population structure and the potential yield of wild stands are highly relevant here since from the very early attempts that eventually resulted in domestication, plant–human interaction was largely dependent upon the biological features of the species involved (e.g., Abbo et al., 2005, 2008, in press; Jackson, 1996; Ladizinsky, 1979, 1987; Rindos, 1984; Zohary, 2004). Both cereals and legumes were adopted as grain crops in prehistoric times in several ancient agricultural centers, e.g., maize and beans in Central America, sorghum and cowpea in Africa (Harlan, 1992). For the Near East, the adoption of legumes and cereals is referred to as a simultaneous process, hence the ‘‘crop assemblage’’ concept (Zohary and Hopf, 2000, p. 242). This ancient and highly successful combination of cereals and legumes is considered as a natural choice due to the complementary nutrient contents of the two crop types (Zohary and Hopf, 2000, p. 92). Studies of plant domestication included considerable work on archaeobotanical assemblages from archaeological sites in the region (see summaries in Garrard, 1999; Zohary and Hopf, 2000; Nesbitt, 2002; and references therein), some archeoethnobotanical observations (e.g., Hillman, 1984; Hillman and Davies, 1990; Simms and * Corresponding author. Tel.: þ972 8 9489443; fax: þ972 8 9489899. E-mail address: [email protected] (S. Abbo). 0305-4403/$ – see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.jas.2008.07.004
Russell, 1997), series of controlled experiments including sowing (see papers in Anderson, 1992, 1999), harvesting and threshing of package plants, use wear analysis on stone tools from the relevant sites in search of evidence for the respective activities on the unearthed tools (e.g., Anderson, 1998; Yamada, 2000) and controlled collection exercises of wild relevant plants, mainly cereals but recently legumes too (Abbo et al., 2008). Cereals were at the focus of much of this research, including controlled field collection of the wild taxa, for understandable reasons, mainly their major role in world economy to this very day. Worthy of note are the pioneering wild wheat harvest of Harlan (1967) in eastern Turkey, Ladizinsky’s (1975) wild cereals collection in the Jordan Valley and the recent work of Kislev et al. (2004). Unlike the above, legumes domestication was rarely discussed in the context of the ecological conditions of their progenitors and cost/benefit considerations concerning their collection for the simple reason that until recently, no controlled wild legume collection data were available (Abbo et al., 2008). Several years ago we initiated a project aiming at better understanding Near Eastern grain legumes domestication. In this framework we studied domestication syndrome traits (Abbo et al., 2002), ancient agrotechnology (Abbo et al., 2003) and nutritional quality (Kerem et al., 2007) in chickpea. Our wild pea harvest was part of this effort (Abbo et al., 2008). Here we report and discuss controlled field collections of lentil and chickpea taxa. The goal of this work is to provide yield data from experimental harvests of two wild lentil species (Lens orientalis (Boiss.) Handel-Mazzeti and Lens odemensis Ladiz.) and one wild small seeded chickpea species (Cicer judaicum Boiss.) as a reference.
S. Abbo et al. / Journal of Archaeological Science 35 (2008) 3172–3177
Mean seed weight of wild lentil is mere 0.01 g or less (Ladizinsky, 1987). Thus far, the available data on wild lentil yield concern only mean number of seeds per plant (Ladizinsky, 1987) but no mean yield per time unit per collector. As to wild lentil collections conducted by the late C. Sperling in eastern Turkey, apparently the results were disappointing (in terms of the grain yield) and were not published (Gideon Ladizinsky, 2007, personal communication). Based on the mean number of lentil seeds per plant and their small mean seed weight, Ladizinsky (1987) concluded that wild lentils could not have been a staple food in pre-agricultural times. L. orientalis is the presumed wild progenitor of domesticated lentil (Ladizinsky, 1999), therefore its yield potential in the wild is highly relevant for the domestication issue, while L. odemensis is a closely related species with a similar seed size that was never domesticated. C. judaicum was chosen as a reference species since its seed size is similar to that of the two above lentil taxa (ca. 0.01 g/seed for Lens sp. and 0.02 g/seed for C. judaicum), its ecological affinities are quite similar to those of the two lentil species, but it was never domesticated. It is worth noting that the wild progenitor of domesticated chickpea (C. reticulatum Ladiz.) known only from southeastern Turkey has much larger seeds, ca. 0.11–0.15 g/seed, similar to the three Near Eastern wild pea taxa (ca. 0.1 g). The results of wild legumes experimental harvest may promote the discussion of the incentives underlying the ancient human choice that led to specific crop domestication. While engaged in the collection, and seed cleaning of these small seeded chickpea and lentils we thought that the obtained data are also relevant for the discussion concerning the use of small grain (SG) plants and their role in the origin of agriculture. The great efforts invested to obtain significant amounts of such SGs, and the presumed role of such ‘‘small seeded resources’’ (Weiss et al., 2004a) were recently interpreted as evidence for broadening the dietary base of preNeolithic communities (Weiss et al., 2004a,b). We think that the picture emerging from our collection exercises enables to further discuss this issue on a more solid ground.
laboratory, each pod was opened, and all mature seeds recovered from each bag weighed. 3. Results The harvest results of the 2006 season (Tables 1 and 3) are based on the average seed yield (g) per plant obtained from the sampled plants, multiplied by the number of observed target plants per run. For the 2007 season, the results (Tables 2 and 4) are in terms of the actual grain yield (g) obtained by each collector during each run (20 or 40 min, while collecting all observed target plants), as well as the calculated return per hour of harvest time. We did not take into account the time of separating the seeds from other plant material, i.e., pods and straw. 3.1. Wild lentil L. orientalis is a short stature plant, rarely exceeding 15 cm height in nature (Fig. 1). It occurs from Turkey to Tadjikistan and from the Crimea to Israel as an element of primary habitats in open or partly shaded formations on shallow/stony soils at altitudes ranging from 500 to 1700 m, and where it is not subject to competition by aggressive cereals or other herbaceous species (for more details on the ecology see, Ladizinsky, 1993). Lens odemensis is also a short stature plant, rarely exceeding 15 cm height with affinity to primary stony and rocky habitats. In Israel it occurs only on soils derived from basaltic bedrock while in Turkey it is known Table 1 Harvest data of wild lentil in northern Israel during the 2006 season Species and sites
Date
Collector and time (min)
No. of plants
Mean yield per plant (g)
Calculated yield (g/h)
L. odemensis Tel Abu-Khanzir
18.5.06
A 50 C 33 E 30 G 50 H 50 I 50 D 50
215 31 4 47 183 105 0
0.1 0.1 0.1 0.1 0.1 0.1 –
25.8 5.6 0.8 5.6 21.9 12.6 0
28.5.06
A 20 A 20 B 20 B 20
72 33 60 30
0.03a 0.01a 0.03a 0a
Tel BaneiGhassan
18.5.06
E 30 C 45 G 45 D 30 H 40
5 88 64 80 40
0.1 0.1 0.1 0.1 0.1
1 11.7 8.5 16 6
Masa’ade forest
19.5.06
A 20 D þ I 20
19 0
–
5.7 0
A 40 C 40 D 40 E 40 G 40 H 40 I 40
54 98 40 96 37 8 0
0.1 0.1 0.1 0.1 0.1 0.1 –
8.1 14.7 6 14.4 5.5 1.2 0
A 40 B 40
16 25
0.07 0.4
2. Materials and methods 2.1. Wild Lens and Cicer harvest Wild Lens and Cicer were harvested in several sites in the Mediterranean district of Israel during the seasons of 2006 and 2007 (Supplementary figure 1). The chosen sites and their physical characteristics are listed in Supplementary table 1. These sites represent the typical plant formations in which the richest populations of wild lentils and wild chickpea occur in Israel. Special efforts were made to select sites free of grazing and protected from current human interference. Activity within nature reserves was conducted under a special license from the Israeli Park & Nature Reserve Authority. Collectors were assigned to a certain area in each site. Each collector was equipped with paper bags and a stopper watch to monitor harvest time. In most sites each collector conducted 2–3 runs, 20–40 min each, placing the collected material of each run into a separate marked bag. In the first year (2006) the collectors counted the number of target plants they encountered while moving in the landscape and sampled random whole ripe plants (between 1 and 23). These sampled plants were threshed by hand over trays in the lab, and their ripened seeds weighed, to allow a calculation of the potential yield per time unit per collector. In the second season (2007) collectors pulled all the target plants they encountered, and placed the whole harvested individuals in marked bags. Following the harvest, paper bags were placed in an oven at 48 C for 3–4 days to dry. The plant material in each bag was carefully separated over trays in the
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L. orientalis Hermon 1
Hermon 1
18.5.06
6.8 0.99 5.4 0
1.68 3.75
Harvesters’ identity: A- Inbar Zezak, B- Efrat Schwartz, C- Shahal Abbo, D- Roi Barak, E- Avi Gopher, G- Mickey Frenkel, H- Ariela Sharvet, I- Alona Rivlin, K – Yigal Aviv, L – Elinor Ben Hanan. a Most plants were completely dry and their pods open.
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S. Abbo et al. / Journal of Archaeological Science 35 (2008) 3172–3177
Table 2 Harvest data of wild lentil in Israel, spring 2007 Species and Site
L. odemensis Tel Abu-Khanzir
Masade Forest
L. orientalis Mt. Hermon (gate)
Collection date
Collectora and time (min)
8.5.07
A 20 K 20
1.74 2.38
C 20 A 20
1.41 1.77
C 20 E 20 A 40 A 20
5.53b 12.42 1.96b 4.21
3.085
16.59 37.26 2.94 12.63
E 20 C 20 A 20
1.61 0.71 2.37
1.16 2.37c
4.83 2.13 7.11
E 20 C 20 A 20
7.71 14.86b 2.8
11.285 2.8c
23.13 44.58 8.4
10.5.07
21.5.07 28.5.07
Mt. Hermon 1
21.5.07 28.5.07
Mt. Hermon 2
Table 4 Harvest data of C. judaicum in Israel, spring 2007
21.5.07 28.5.07
Actual yield (g)
Mean yield per exercise (g)
Calculated potential (g/h)
2.06
5.22 7.14
1.59
4.23 5.31
8.975
a
For harvesters’ identity, see legend of Table 1. In addition to lentils 0.38, 0.06, 0.46 g, respectively, of Lathyrus aphaca seeds were taken into the collection bags. c No statistics, single go. b
from both basaltic and calcareous regions (Ladizinsky, 1993). In most parts of their natural distribution range, populations of these species occur in patches and are often pretty thin comprising of only few individuals, however, the locations chosen for the experimental harvest support massive populations with relatively rich
Table 3 Harvest data of wild Cicer judaicum during the 2006 season in several sites, Israel Site
Date
Collectora and time (min)
No. of plants
Mean pods per plant
Calculated maximal yield per plant (g)b
Shilat Forest
18.4.06
E 20 E 20 E 20 A 20 A 20 A 20 D 20 D 20 D 20
4 12 0 14 1 4 15 4 5
23.25 8.42
0.47 0.17
5.64 6.12
2.79 3 3 2.47 4.25 5.80
0.05 0.05 0.06 0.05 0.08 0.12
2.35 0.15 0.72 2.22 1.02 1.74
E 20 E 20 E 20 A 20 A 20 A 20 D 20 D 20 D 20
9 0 5 7 3 4 7 0 8
2.67
0.04
1.17
6 5.29 6 8.75 2.43
0.12 1.1 0.12 0.18 0.05
1.8 2.2 1.1 2.1 1.02
3
0.06
1.44
Modiin
18.4.06
Calculated yield (g/h)
Modiin
21.4.06
C 30 E 45
55 37
8.8 3.68
0.18 0.07
19.36 3.45
Shoham 2
28.4.06
E 20
32
2.28
0.05
4.8
Shoham 3
28.4.06
E 20 E 20 E 20
24 24 9
3.21 1.83 5.22
0.06 0.04 0.10
4.6 2.88 2.81
a
For harvesters’ identity, see legend of Table 1. The calculation was based on seed weight of 0.02 g and mean number of one seed per pod. b
Site
Collection date
Collectora and time (min)
Actual yield (g)
Modii’n 1
27.4.07
A 20 I 20 H 20 L 20
1.27 0.86 0.42 0.19
A 30 I 30 H 30 L 30
1.05 0 2.29 0.01
A 20 I 20 H 20 L 20
2.21 3.32 1.04 0.7
A 20 I 20 H 20 L 20
1.02 0.89 0.11 0.86
A 20 I 20 H 20 L 20 A 20 I 20 H 20 L 20
0.92 0.71 0 0.74 1.98 0.47 1.49 1.82
C 20 C 25 C 20 E 20 E 20 E 20
2.41 6.12 6.73 0.09 0.86 2.19
Modii’n 2
Modii’n 3
Shilat Forest 1
Shilat Forest 2
Mevo – Horon
27.4.07
27.4.07
27.4.07
27.4.07
4.5.07
Mean yield per exercise (g)
Calculated yield per hour (g/h)
0.68
3.83b 2.58 1.26 0.58
0.83
2.1 0 4.58 0.02
1.82
6.63 9.96 3.12 2.1
0.72
3.06 2.67 0.33 2.58
1.01
2.76 2.13 0 2.22b 5.94b 1.41 4.47 5.46
3.06
7.23 14.69 20.19 0.27 2.58 6.57
a
For harvesters’ identity, see legend of Table 1. b In addition (to chickpea), 0.73, 0.37 and 0.1 g, respectively, of P. fulvum seeds were collected.
stands. Even in such ‘‘rich’’ wild lentil habitats, there is a great difficulty to harvest large amounts due to the distribution pattern of the plants. An illustration for this is given in Supplementary figure 2, with the frequency distribution of L. odemensis plants spotted on 30 cm to each side of a measuring tape along a 30 m transect in Tel Banei-Ghassan, northern Golan (see Supplementary figure 1). The grain yields from collections conducted during the 2006 season were highly variable (Table 1). The number of plants observed by the individual collectors varied between 0 and 215, demonstrating the irregular distribution of the species in the studied habitats. This wide variation in plant density was typical for the two species in all sites. The grain yield of L. odemensis, ranged between 0 and 25.8 g/h while that of L. orientalis never exceeded 15 g/h in 2006. It should be noted that in 20 out of 27 total runs of lentil harvest (two species), the calculated yield per hour was below 10 g (Table 1). The yield figures for the collection season of 2007 are pretty similar to the previous year (Table 2). Grain yields ranged between 2.13 and 37.26 g/h. The maximal yield obtained in 2007 was in L. orientalis. Similar to the situation in 2006, in nine out of 14 total harvest runs, the calculated yield was below 10 g/h (Table 2). In 2007 we collected all the observed target plants while moving across the site. Because lentil plants usually grow in mix stands with other creeping legumes such as Lathyrus, Vicia, Medicago, and Trifolium spp. among others, it often happened that non-target plants were taken into the collection bags (Table 2 and discussion below).
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In the 2006 season, the number of Cicer plants observed by the collectors varied between 0 and 55 (Table 3). The mean number of pods per sampled plant was also highly variable and ranged from either 1 or 0 to more than 20. Consequently the calculated grain yield ranged from close to 0 to nearly 20 g/h (Table 3). Similar to the 2006 results, the actual grain yields obtained during the 2007 season ranged between 0 and 6.7 g with a maximum of nearly 20 g/h (Table 4). 4. Discussion
Fig. 1. A typical wild lentil (Lens orientalis) plant with green and ripened pods.
3.2. Wild chickpea C. judaicum is a short stature plant mostly confined to stony and rocky niches where competition with more aggressive annuals is small (Fig. 2). Unlike the above wild lentils that form massive stands in parts of their range, C. judaicum has a patchy distribution pattern at all levels, from local niche to the region and beyond (for more details on its ecology see, Ben David et al., 2006). The locations chosen for the experimental harvest support the richest populations known to us based on an 8 years survey across the distribution of this species in Israel and Jordan (Ben David et al., 2006; Abbo, unpublished data).
This report describing controlled field harvests of wild lentil and chickpea in 2006 and 2007 relies also on our long-term experience with many of the areas and plant populations studied. Our field work during the past 8 years indicates that while some lentil populations are rich (with hundreds of plants easily found in less than an hour), wild chickpea populations are always small and highly patchy. Most of the collection sites were harvested in both seasons, e.g., Shilat Forest, Tel Abu-Khanzir, Mt. Hermon 1 while some were visited in one season only, e.g., Mt. Hermon (gate, 2) and Modiin 3 in 2007, or Tel Banei-Ghassan in 2006. In the past 8 years we have observed high variability in plant establishment from year-to-year. This phenomenon of erratic year-to-year establishment is a known characteristic of wild lentils (G. Ladizinsky’s unpublished field diaries). Therefore we cannot deduce on the effect of the first year collection on the plant stand in the second year. We assume that at the beginning of our study the seed bank in all of the sites was in equilibrium, and that the year-to-year yield variability seen in some of our stations is not a direct result of our preceding harvest. The grain yield results of our experimental harvests certainly support the idea that low yielding small seeded legumes such as wild lentils as well as small seeded chickpea were not a substantial food (staple) resource in hunter-gatherer subsistence economy. This idea was first put forward by Ladizinsky (1987) to support his model suggesting that a mutation for free germination had to establish itself in wild lentil populations prior to domestication (pre-adaptation for domestication). Indeed, the erratic year-to-year germination combined with the low yield potential of lentil makes it difficult to understand why wild L. orientalis was adopted as a crop plant in the first place. A similar suggestion was recently made concerning wild pea yield, based on the fact that among the three wild pea species native to Israel, the one adopted for domestication is the least productive (Abbo et al., 2008). The relatively low productivity of some of the wild progenitors of the Near Eastern grain legumes is in sharp contrast to grain yields obtained from the massive wild wheat and barley stands typical of the oak–pistachio park forest belt of the eastern Mediterranean (Harlan and Zohary, 1966), which allow to harvest from 200 g to more than 1 kg of grain per hour (appendix of Abbo et al., 2008; Harlan, 1967; Kislev et al., 2004; Ladizinsky, 1975). Several questions emerge from the data and the insights of our study: Why bother with wild plants that cannot provide even 100 g of seeds per hour of collection? Or in a more general way, why bother with small seeded plants at all? And more specifically, why did Neolithic people opt to adopt one specific small seeded lentil out of several available wild lentil species? Why was L. orientalis and not other Lens sp. with a similar potential taken for domestication? There may be two major lines of explanation: [i] That the small seeded legume species, in general, had some advantages (and possibly more so, the chosen ones). [ii] That there were (stressful?) conditions that pushed people to exploit these ‘inefficient’ species.
Fig. 2. A typical wild chickpea (Cicer judaicum) plant with green pods. For scale, pen length is 13 cm.
The first explanation relies on an earlier study on chickpea domestication that indicated a significant increase in the
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concentration of the essential amino acid tryptophan in the domesticated stock (Kerem et al., 2007) and its many advantages for Neolithic people. The grain yield results of a recent study on wild pea harvest also stress the possible role of seed composition and nutritional value (Abbo et al., 2008). We assumed that pea (Abbo et al., 2008), and we assume here that possibly lentil as well, if available in an appreciable amount may have provided certain nutritional benefits. Another possible advantage of collecting and later domesticating these legumes is especially important in the context of combining several food sources based on cultural traditions gained through a long adaptive process (e.g., Jackson, 1996). Prehistoric people may have developed a taste for lentil (or pea) upon gathering from the wild, but our yield data for pea (Abbo et al., 2008) and for lentil and chickpea (herein) indicate that this must have been a seasonal rare occasion. To satisfy the desire for pea/lentil soup – or any other food prepared from these plants – on a regular basis, one had to grow plots of pea or lentils. If we accept the importance of lentils for the diet, this can be seen as an incentive for domestication. We stress the relative importance of grain legumes based on the observation that wild cereals’ seeds are an easy-to-obtain and relatively stable resource while wild legumes populations are unreliable and difficult to exploit (Abbo et al., 2008; Ladizinsky, 1987). Another interesting feature worthy of note is that while chickpea shows ‘improved’ nutritional aspects after domestication (e.g., more tryptophan), emmer wheat domestication for example involved an appreciable reduction in seed protein (Avivi, 1978; Uauy et al., 2006). This may provide yet another clue to the importance and the possible role of grain legumes protein in the diet of early agricultural communities. So, collecting and later domesticating legumes to make them an important dietary staple may have provided some basic needs. Discussing the second, stress-related explanation would eventually require a deeper look at the Broad Spectrum Revolution (BSR) issue. While an in-depth discussion of the BSR hypothesis as presented by Flannery (1969) and its implications for the study of the origin of agriculture are beyond our scope, we wish to address a certain aspect of the subject following some published ideas based on archaeobotanical finds (Weiss et al., 2004a,b). The studies by Weiss et al. (2004a,b) are unique attempts to test the BSR hypothesis using botanical finds. In doing so, Weiss et al. (2004a,b) presented and discussed their remarkable archaeobotanical data from Ohalo II, a 23,000 years old site in Israel. They analyzed >90,000 plant remains and classified some 142 different taxa. Some 16,000 remains were small seeded cereals grains – Small Grain Grasses (SGG). To quantify the contribution of SGGs to the total plant food mass, Weiss et al. (2004b) calculated the volume ratio between the SGGs and the large seeded wild cereals (wheat and barley), concluding that SGGs constitute 34.6% of the total grain volume. Hence, they see these SGG (cereals) grains as staple food, first because of the large number of seeds found, and the fact that the seeds were fully mature; and second by noting the fact that these were found in a brush hut next to a grinding stone – that is, in a domestic consumption context (see also Weiss et al., 2008). They also use ethnographic analogies and evidence collected among hunters-gatherers and present-day traditional agriculturalists in support of their interpretation. They claim that the small grain size of these SGGs makes them very costly and difficult to collect because of their low stature and the high labor requirement for dehusking as compared with the seeds of large seeded cereals. The volume-based calculation is acceptable since a tight linear relationship between grain volume and weight exists in wheat (Millet and Pinthus, 1984). Based on a scatter diagram of more than 160 wheat samples (Millet and Pinthus, 1984), this relationship could be depicted as follows: weight in mg ¼ 1.1 þ1.34 (volume in mL). The histogram presented by Weiss et al. (2004b) considers
the volume of most of the SGG to be around 2 mL. So, according to the equation above: 1.1 þ1.34 2 ¼ 3.78 mg per single SGG; and thus 16,168 SGG seeds 3.78 mg ¼ 61,115 mg, or 61.1 g. If we follow the same calculation for the wheat–barley assemblage, then: 1.1 þ1.34 45 mL ¼ 61.4 mg per grain; and thus 2605 grains 61.4 ¼ 159,947 mg or 159.9 g. So according to the calculated weight fractions, SGGs made 27.6% of the total cereals remains in Ohalo II, which is quite close to the 34.6% volume fraction (Weiss et al., 2004b). Just before we discuss these data, we would like to highlight an observation we made during field work that might be of significance. In a few instances we obtained some non-target seeds while collecting lentil plants (Table 2). This happened because in natural habitats lentil plants grow intermingled with many other plant taxa (see Section 2). Despite strict instructions to the collectors and effort to focus only on the target species, in one case 0.38 g of Lathyrus seeds were collected alongside 5.53 g of lentil seeds, in the second case 0.06 g of Lathyrus seeds were collected with 1.96 g of lentil seeds and in the third case 0.46 g of Lathyrus seeds were found in the bag that contained 14.86 g of lentil seeds. The fraction of the Lathyrus seeds in the original samples (lentil þ Lathyrus) was 6.4%, 2.9% and 3% for the three above cases, respectively. This finding allows a rare opportunity to assess claims on the role of different small seeded sources in the ancient diet. For the sake of the discussion we assume that 80% of the target food species (e.g., lentil in our case), seeds are retained and later consumed and therefore will not be preserved on-site, while a similar fraction of the non-target (Lathyrus in our case) is rejected while cleaning the harvested plant material and hence is more likely to be found on-site if preserved. Applying the above 80% rejection vs. retention rates [namely, that 80% of the lentil seeds are consumed and 80% of the Lathyrus seeds are not consumed] to our harvest figures results in significant ‘enrichment’ for the non-target species from a mere 6.4 to 21%, from 2.9 to 10% and from 3 to 11% (more than threefold increase in all cases). Note the 27.6% SGG remains out of the total Ohalo II cereals calculated following Weiss et al. (2004b). We have no safe way to estimate the extent of yield contamination with non-target species in prehistoric time in general or in the case of Ohalo II in particular, because we have no information on the ancient harvest methods. Moreover, we cannot estimate the contribution of vegetal material used for adobe walls, or for hut roofs to the archaeobotanical finds. In fact, in the case of Ohalo II, Nadel et al. (2004) report on SGG grasses found in the same sort of huts used as bedding for sleeping areas including the very same species later mentioned as SGG staple food (Weiss et al., 2004a,b). The above discussion calls for a reconsideration of the attitude to plant remains in prehistoric sites, and extends beyond Weiss et al. (2004a,b). Is there a direct relationship between the composition of plant remains found in archaeological sites and the role of the different species in the diet? For example, is the assumption that major plant remains found on-site represent the ancient diet valid (Savard et al., 2007, p. 182)? Is it right to actually consider any amount of small seeded plants as staple food sources without questioning, especially when relating to the Neolithic Revolution? Are there biases caused by formation processes of the sites and human behavior relating to aspects other than food? As long as plant remains found on-site appear in minute quantities, like in the case of the single Cicer seed found in the Mousterian (60–50,000 YBP) Kebara Cave (Lev et al., 2005) and given the meager grain yield obtained in our experimental harvests as well as the possible effect of contamination while collecting, the definitions of such remains as ‘‘food remains’’ (let alone ‘‘staples’’) is not acceptable. In cases of larger numbers of botanical remains, like the case of Ohalo II (Weiss et al., 2004a,b), the question becomes worthy of an in-depth look. We are not given data
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concerning the distribution of these SGG taxa in the region around Ohalo II, nor on the potential of such wild stands in terms of grain yield per collection time unit to support the hypothesis regarding their staple role in the diet of the Ohalo II inhabitants. If we consider the grain yields obtained for small seeded legumes in our controlled collections (herein); and the possibility that some of the plant remains recovered from archaeological excavations do not directly reflect the target food species (‘shopping’) list of the food gatherers; and if we consider the possibility of other sources of botanical finds beyond food remains (like construction and bedding materials as in the case of Ohalo II, Nadel et al., 2004); and, in light of the possible bias in favor of non-target plants resulting from human behavior and the specifics of the depositional (site formation) processes; and, based on some of the above calculation concerning the weight of the collected SGG; we may cautiously say that SGGs cannot comfortably and easily be seen as staple foods even in cases when the assemblage is large, well analyzed and species-rich like that of Ohalo II. Our study points out the importance of controlled, experimental field harvests both for better understanding the natural setting of these plants and finding out the practicalities of their exploitation. Our data also contribute to a better understanding of the archaeobotanical record and its formation processes. Furthermore, it sheds light on the considerations leading to the choices people made in the past, and this in turn improves our understanding of the mechanisms and motivations behind plant domestication. 5. Note added in proof A recent report by Melamed et al. (2008) claims that the toxic Vicia peregrina was a cultivated crop in its own right for human food. However, applying our 80% rejection (for non-target species); 80% consumption (for target species) rates to the numbers provided by Melamed et al. (2008) results in the V. peregrina seeds making 28% of the lentilþVicia seeds. Note the 27.6% SGG fraction of Weiss et al. (2004b) in our discussion (above) which casts doubt on the presumed dietary role of the V. peregrina seeds Melamed, Y., Plitman, U., Kislev, M.E., 2008. Vicia peregrina: an edible early Neolithic legume. Vegetation History and Archaeobotany. doi:10.1007/s00334-008-0166-6. Acknowledgements SA and AG thank the Israel Science Foundation for financial support (Bikoorah grant no. 1406/05). We thank Prof. Gideon Ladizinsky for many years of fruitful interaction and learning. Appendix. Supplementary data Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j.jas.2008.07.004 References Abbo, S., Lev-Yadun, S., Galwey, N., 2002. Vernalization response of wild chickpea. New Phytologist 154, 695–701. Abbo, S., Shtienberg, D., Lichtenzveig, J., Lev-Yadun, S., Gopher, A., 2003. Chickpea, summer cropping, and a new model for pulse domestication in the ancient Near-East. Quarterly Review of Biology 78, 435–448. Abbo, S., Lev-Yadun, S., Rubin, B., Gopher, A., 2005. On the origin of Near Eastern founder crops and the ‘dump-heap hypothesis’. Genetic Resources and Crop Evolution 52, 491–495. Abbo, S., Zezak, I., Schwartz, E., Lev-Yadun, S., Gopher, A., 2008. Experimental harvesting of wild peas in Israel: implications for the origins of Near East farming. Journal of Archaeological Science 35, 922–929. Abbo, S., Saranga, Y., Peleg, Z., Lev-Yadun, S., Kerem, Z., Gopher, A. Reconsidering domestication of legumes vs. cereals in the ancient Near East. Quarterly Review of Biology, in press.
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