The Neolithic Southwest Asian Founder Crops
2011; University of Chicago Press; Volume: 52; Issue: S4 Linguagem: Inglês
10.1086/658367
ISSN1537-5382
Autores Tópico(s)Pacific and Southeast Asian Studies
ResumoPrevious articleNext article FreeThe Neolithic Southwest Asian Founder Crops Their Biology and ArchaeobotanyEhud Weiss and Daniel ZoharyEhud Weiss and Daniel ZoharyPDFPDF PLUSAbstractFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreAbstractThis article reviews the available information on the founder grain crops (einkorn wheat, emmer wheat, barley, lentil, pea, chickpea, and flax) that started agriculture in Southwest Asia during the Pre-Pottery Neolithic period, some 11,000–10,000 years ago. It provides a critical assessment for recognizing domestication traits by focusing on two fields of study: biology and archaeobotany. The data in these fields have increased considerably during the past decade, and new research techniques have added much to our knowledge of progenitor plants and their domesticated derivatives. This article presents the current and accumulated knowledge regarding each plant and illustrates the new picture that emerged on the origin of agriculture.IntroductionThe occasion of the Wenner-Gren conference “The Origins of Agriculture: New Data, New Ideas” raised our awareness of the importance of critical, high-quality data. We suspected that the newly obtained data sets from well-dated archaeological contexts may generate new hypotheses concerning the first steps of the agricultural revolution in Southwest Asia.For this purpose we concentrated on two domains: the newly obtained rich archaeobotanical assemblages and the molecular analysis of present-day accessions. Some of these new data are inconclusive for pinpointing the shift from wild to domesticated plants because of bad preservation of the archaeological samples and problematic field or lab procedures. Following the fruitful discussions during the conference, we critically reassessed the available archaeobotanical data in an attempt to “separate the grain from the chaff.” In the following pages we present the data sets, both old and new, that we consider to be reliable enough to indicate the first appearances of domesticated forms in the Fertile Crescent.Eight plants are considered to be the domesticated founder crops in the Levant (i.e., the western “arc” of the “Fertile Crescent”; Table 1). This assemblage includes three cereals (einkorn wheat Triticum monococcum, emmer wheat Triticum turgidum subsp. dicoccum, and barley Hordeum vulgare), four pulses (lentil Lens culinaris, pea Pisum sativum, chickpea Cicer arietinum, and bitter vetch Vicia ervilia), and a single oil and fiber crop (flax Linum usitatissimum).Table 1. Eight founder grain (three grass [cereal], four legume [pulse], and one oil and fiber) crops and their wild progenitors that started Neolithic agriculture in the LevantDomesticated cropWild progenitorCommon nameScientific nameCommon nameScientific nameEinkorn wheatTriticum monococcum subsp. monococcumWild einkornT. monococcum subsp. baeoticumEmmer wheatTriticum turgidum subsp. dicoccumWild emmerT. turgidum subsp. dicoccoidesBarleyHordeum vulgare subsp. distichumWild barleyH. vulgare subsp. spontaneumLentilLens culinarisWild lentilLens orientalisPeaPisum sativumWild peaPisum humileChickpeaCicer arietinumWild chickpeaCicer reticulatumBitter vetchVicia erviliaWild bitter vetchVicia erviliaFlaxLinum usitatissimumWild flaxLinum bienneView Table ImageFrom many aspects these eight plants belong to the same group—the grain crops. All of them are annuals, self-pollinated, diploid (except emmer wheat), native to the Fertile Crescent belt, and interfertile within each crop and between the crop and its wild progenitor. Both the agronomic compensation and the dietary complementation between plants in this group have been appreciated since the early days of agriculture up until now.The aim of this article is to review the available information on these founder crops that started agriculture in the Levant during the Pre-Pottery Neolithic (PPN) period some 11,000–10,000 years ago (Table 2). We shall review the current knowledge of these plants by focusing on two fields of study: (i) biology and (ii) archaeobotany. Biological data derived from the research on living plants can indicate what the wild progenitors of the domesticated plants may have been and what the selection pressures for domesticated types were. Archaeobotanical information identifies the plants used by hunting and gathering groups, which were the plants first domesticated, and when and where these processes took place.Table 2. Cultural-historical sequence for the Southern Levantine Pre-Pottery Neolithic periodsPeriod and entity/phaseCalibrated 14C years BPLate Epipaleolithic, Final Natufian12,500–11,700PPNA11,600–10,500PPNB: Early10,500–10,100 Middle10,100–9500 Late9500–8750 Final/PPNC8750–8400Early Pottery Neolithic, Yarmukian8400–7600Sources. Goring-Morris and Belfer-Cohen 2011; Kuijt and Goring-Morris 2002.Note. PPNA = Pre-Pottery Neolithic A; PPNB = Pre-Pottery Neolithic B; PPNC = Pre-Pottery Neolithic C.View Table ImageLarge amounts of critical new data, botanical and archaeological, have been gathered in the Fertile Crescent belt in the past 40 years (fig. 1). These findings established the Levant as the critical area for understanding early domestication of both plants and animals (and see additionally Zeder 2011). (Note that we use the terms “Southwest Asia” and “Near East arc” interchangeably in this article; we also use the term “Levant” to refer to the western horn of the Fertile Crescent in the Near East.)Figure 1. Distribution of Epipaleolithic and Pre-Pottery Neolithic sites mentioned in the text.View Large ImageDownload PowerPointIn this article we will adopt a critical assessment intended to recognize domestication traits in Levantine archaeobotany (Zohary, Hopf, and Weiss 2011). In some way this assessment is partially intended to follow and update Mark Nesbitt’s (2002) article. The basics of this assessment are twofold.1. The most reliable trait for the identification of domestication is ear shattering in the cereals, pod indehiscence in the pulses, and capsule indehiscence in flax. In wild plants, ears and pods/capsules disarticulate at maturation and shatter the seed-dispersal devices or the seeds; in contrast, ears and pods/capsules stay intact in the domestic plant. This trait is the best effective diagnostic indication for recognizing grain-crop domestication (i.e., the shift from wild plants to domesticated plants), which is controlled mostly by a single major gene locus or two such loci (Table 3).Table 3. Recessive mutations that changed wild-type trait into domestic-type trait in the Near East founder cropsCropWild-type traitDomestication traitNo. recessive mutationsSourceEinkorn wheatShattering earsNonshattering ears1Love and Craig 1924Emmer wheatShattering earsNonshattering ears2Sharma and Waines 1980BarleyShattering earsNonshattering ears2Takahashi 1955; Zohary 1960:41LentilDehiscent podDehiscent pod1Ladizinsky 1979PeaDehiscent podIndehiscent pod1Waines 1975ChickpeaDehiscent podIndehiscent pod1Kazan et al. 1993Bitter vetchDehiscent podIndehiscent podUnknown FlaxDehiscent capsuleIndehiscent capsule1Diederichsen and Hammer 1995; Gill and Yermanos 1967Note. These mutations are responsible for the shift from wild-type seed dispersal to human-dependent crops. There is no conclusive information yet regarding the situation in bitter vetch.View Table Image2. The second diagnostic morphological trait is seed size. In the wild progenitors the seeds are relatively small, while in domesticated plants they are frequently larger. This trait takes longer to develop, it is variable within the plant community, it is apparently a later development under domestication, and it is not as diagnostic as the first trait. This trait is controlled by various genes and other factors.Additional markers for domesticated traits (e.g., Fuller 2007) are relevant mostly for differentiating between wild and domesticated traits in living plants. This is apparently much less so in the archaeobotanical assemblage.During the past decade or so, molecular studies became central in research toward understanding the beginning of agriculture. Whether the mode of domestication was monophyletic or polyphyletic, these studies went in two lines (Brown et al. 2009). In the first half of this decade, molecular studies were regarded as supporting monophyletic origin of a single localized event or at least very rare events (e.g., Badr et al. 2000; Heun et al. 1997; Özkan et al. 2002). In the second half, however, such studies were interpreted as supporting polyphyletic domestication of multiple events in more than one location, such as of einkorn wheat (Kilian et al. 2007) and barley (e.g., Molina-Cano et al. 2005; Morrell and Clegg 2007). An attempt is made to evaluate the available knowledge, crop by crop, for the above-mentioned signs of the earliest definite domesticates as well as molecular and other biological data.From the eight founder crops, this article does not deal with bitter vetch Vicia ervilia. According to its large quantities in Neolithic contexts, this pulse might have been taken into domestication in Anatolia or the Levant (i.e., in the general area in which it still grows wild today). However, because currently there are no reliable diagnostic traits to morphologically discriminate between its wild and domesticated forms in archaeological remains, the early Turkish finds could be either.The source of most dates is Radiocarbon CONTEXT database (Böhner and Schyle 2002–2006). Table 4 lists the uncalibrated and calibrated radiocarbon dates. In an attempt to simplify understanding of the domestication process, all dates in the text are representative dates only and were rounded to the nearest 50 years (please refer to Table 4 for range of dates). Periods mentioned in this article, such as Pre-Pottery Neolithic A (PPNA) or Early Pre-Pottery Neolithic B (EPPNB), do not necessarily imply cultural similarities but are used for the convenience of comparing among sites that belong to the same approximate time period.Table 4. Representative radiocarbon datesSiteLab no.14C dates BPCal BP (1σ)13CDated materialPeriodAbu HureyraOxA-8818870 ± 10010,180–9790…Bone/ovicaprine, burntPPNBAbu HureyraBM-1724R8020 ± 1009093–8710…CharcoalPPNBAli KoshB-1227218540 ± 909600–9440…Organic material/carbonPPNAli KoshB-1082568000 ± 509000–8770…Organic material/carbonPPNArpachiyahP-5858064 ± 789090–8770…Charcoal/ashChalcolithicArpachiyahBM-15316930 ± 607830–7680…CharcoalChalcolithicBeidhaP-13809128 ± 10310,480–10,200…CharcoalPPNBBeidhaP-13798546 ± 1009630–9440…Pistacia, nutsPPNBCafer HöyükLy-44369560 ± 19011,200–10,650…CharcoalEPPNBCafer HöyükLy-44378950 ± 8010,220–9920…CharcoalEPPNBCan Hasan IAA-411707853 ± 368700–8580…Charcoal/juniperEarly ChalcolithicCan Hasan IP-7936254 ± 787270–7020…CharcoalEarly ChalcolithicCan Hasan IIIHU-118584 ± 659610–9490…CharcoalAceramic NeolithicCan Hasan IIIHU-97874 ± 708780–8580…CharcoalAceramic NeolithicCayönüGrN-62439320 ± 5510,590–10,420…CharcoalEPPNBCayönüGrN-62448980 ± 8010,240–9930…CharcoalEPPNBChoga MamiBM-4836846 ± 1827930–7560…CharcoalNeolithic/SamarraGilgalPta-45889920 ± 7011,470–11,230…CharcoalPPNAGilgalPta-45859710 ± 7011,230–11,080…CharcoalPPNAJerichoP-3828956 ± 10310,230–9910…CharcoalPPNBJerichoBM-13208539 ± 649550–9480…CharcoalPPNBKissonerga-MylouthkiaOxA-74609315 ± 6010,650–10,410…NDCypro-EPPNBKissonerga-MylouthkiaAA-331299110 ± 7010,380–10,200…NDCypro-EPPNBMureybitP-12249492 ± 12210,880–10,580…CharcoalPPNAMureybitLv-60710,590 ± 14012,800–12,390…CharcoalPPNANetiv HagdudPta-45579780 ± 9011,320–11,090…CharcoalPPNANetiv HagdudPta-45569660 ± 7011,200–11,060…CharcoalPPNAOhalo IIRT-162420,840 ± 29025,500–24,600−20.60CharcoalMasraqanOhalo IIRT-129717,500 ± 20020,950–20,350−22.70CharcoalMasraqanParekklisha-ShillourokambosLy-2909310 ± 8010,660–10,400…NDCypro-EPPNBParekklisha-ShillourokambosLy-9308670 ± 809740–9530…NDCypro-EPPNBRamadGrN-44268210 ± 509270–9030…CharcoalPPNBRamadGrN-48218090 ± 509130–8980…CharcoalPPNBRizokarpaso-Cape-Andreas-KastrosMC-8057775 ± 1258720–8410…NDCypro-PPNBRizokarpaso-Cape-Andreas-KastrosMC-8077450 ± 1208390–8160…NDCypro-PPNBTepe SabzI-15017460 ± 1608420–8050…CharcoalObeidTepe SabzI-15005410 ± 1606400–5990…CharcoalObeidYiftahelKN 35719100 ± 8010,390–10,190…Horsebean seedsMPPNBYiftahelRT 736A8570 ± 1309740–9430…Horsebean seedsMPPNBNote. PPN = Pre-Pottery Neolithic; PPNA = Pre-Pottery Neolithic A; PPNB = Pre-Pottery Neolithic B; EPPNB = Early Pre-Pottery Neolithic B; MPPNB = Middle Pre-Pottery Neolithic B; ND = unknown.View Table ImageCerealsEinkorn Wheat Triticum monococcumBiologyEinkorn is a small plant, rarely more than 70 cm high, with a relatively low yield, but it survives on poor soils where other wheat types usually fail. It is a relatively uniform diploid (2n=2x=14 chromosomes) wheat with characteristic hulled grains and delicate ears and spikelets. Most domesticated einkorn varieties produce one grain per spikelet, hence its name, but cultivars with two grains exist as well (Harlan 1981; Schiemann 1948).The wild ancestry of domesticated einkorn wheat is well established. Domesticated Triticum monococcum is closely related to a group of wild and weedy wheat forms spread over Southwest Asia and adjacent territories and traditionally referred to as “wild einkorn” or Triticum boeoticum. The most distinguishing trait between wild einkorn and domesticated einkorn is the mode of seed dispersal. Wild forms have brittle ears, and the individual spikelets disarticulate at maturity to disperse the seed. In domesticated einkorn the mature ear remains intact and breaks into individual spikelets only on pressure (threshing). The shape of the grain is another diagnostic character indicating domestication (van Zeist 1976). In domesticated forms, the kernels tend to be wider compared with the wild forms.Wild einkorn is widely distributed over Western Asia and penetrates also into the southern Balkans (Harlan and Zohary 1966; Zohary, Harlan, and Vardi 1969). Its distribution center lies in the Fertile Crescent (i.e., northern Syria, southern Turkey, northern Iraq, and adjacent Iran, as well as some parts of western Anatolia; fig. 2). In these regions, wild einkorn is massively distributed as a component of oak park-forests and steppelike formations.Figure 2. Distribution of wild einkorn wheat Triticum monococcum subsp. baeoticum (=Triticum baeoticum). The area in which wild einkorn is massively spread is shaded. Dots represent additional sites outside the main area harboring mainly weedy forms (Zohary, Hopf, and Weiss 2011).View Large ImageDownload PowerPointHeun and colleagues (Heun, Haldorsen, and Vollan 2008; Heun et al. 1997) analyzed domesticated and wild einkorn from the Fertile Crescent and beyond for amplified fragment length polymorphism (AFLP) DNA analysis. According to their research, wild einkorn wheat was domesticated in the Karacadağ range in southeast Turkey. It also supports the assumption of its monophyletic origin. These findings were recently supported by Kilian et al. (2007), who found, however, that several domesticate lines arose at the beginning of einkorn cultivation (i.e., that einkorn went through a number of independent domestication events). These lines are all part of the einkorn gene pool that grows wild in southeastern Turkey.ArchaeobotanyThe earliest definite domesticated einkorn wheat appears in two EPPNB sites, namely ca. 10,600–9900 cal BP Çayönü (van Zeist and de Roller 1991–1992, 2003) and Cafer Höyük (de Moulins 1997), southern Turkey (fig. 1). In these sites, situated within the present range of distribution of wild einkorn (fig. 2), numerous charred spikelet forks were found showing rough breakage scars.From these localities, einkorn spreads farther south to Middle Pre-Pottery Neolithic B (MPPNB), ca. 10,200–9550 cal BP, Tell Aswad near Damascus (van Zeist and Bakker-Heeres 1982 [1985]) and Jericho (Hopf 1983), where its remains, however, are relatively few. Generally, this wheat appears to be less frequent than the emmer wheat and barley.Emmer and Durum-Type Wheats Triticum turgidumBiologyTriticum turgidum is a varied aggregate of domesticated and wild tetraploid (2n=4x=28 chromosomes) wheats. According to their response to threshing, the domestic turgidum wheats fall into two groups of cultivars that are recognizable in archaeological remains.1. Hulled nonshattering emmer wheat, Triticum turgidum subsp. dicoccum (traditionally called Triticum dicoccum), in which the products of threshing are the individual spikelets. The grains remain invested by the glumes and pales. In domestic emmer, as in einkorn, threshing results in breaking the rachis of the ear in its weakest points below each spikelet. Emmer represents the primitive situation in domesticated turgidum wheats.2. The more advanced free-threshing emmer, which evolved under domestication from hulled emmer. This is a group of intraspecific taxa; its common representative today is durum wheat, T. turgidum conv. durum. The glumes in all these domesticated tetraploid types are relatively thin. Threshing breaks the glumes at their bases and frees the naked grains. The rachis is usually uniformly tough. Threshing breaks it into irregular fragments.Hulled emmer (T. turgidum subsp. dicoccum) was the principal wheat of Old World agriculture in the Neolithic and early Bronze Age.Genetic and morphological evidence clearly indicates (for review, see Feldman, Lupton, and Miller 1995; Zohary 1969) that the domesticated tetraploid turgidum wheats (both hulled dicoccum forms and free-threshing durum-type varieties) are closely related to wild wheat native to Southwest Asia and traditionally called Triticum dicoccoides (wild emmer wheat). This is annual, predominantly self-pollinated wheat with characteristic large and brittle ears and big elongated grains that show a striking similarity to some domesticated emmer and durum cultivars.In the tetraploid turgidum wheats, the most conspicuous diagnostic difference between wild and tame is the seed-dispersal mechanism (Zohary 1969; Zohary and Brick 1961). Wild dicoccoides wheats have brittle ears that shatter on maturity into individual spikelets. Each spikelet operates as an arrowlike device disseminating the seed by inserting them into the ground. The “wild-type” rachis disarticulation and the spikelet morphology reflect specialization in seed dissemination that ensures the survival of the wild forms under wild conditions. In the human-made system of reaping, threshing, and sowing, this major adaptation broke down, and selection resulted in the evolution of human-dependant nonbrittle types. Significantly, the shift from a brittle spike (in wild dicoccoides wheats) to a nonbrittle spike (“hulled type” in domesticated dicoccum wheats) is governed by a single recessive mutation in a major gene (Table 3). In addition, wild and domesticated forms differ from one another in kernel morphology (van Zeist 1976). In domesticated dicoccum and durum forms, the grain tends to be wider and thicker as well as rounder in cross section compared with the wild dicoccoides counterpart.Wild emmer, T. turgidum subsp. dicoccoides, is more restricted in its distribution and more confined in its ecology than wild einkorn. Its range covers Israel, Jordan, southwestern Syria, Lebanon, southeastern Turkey, northern Iraq, and western Iran (fig. 3).Figure 3. Distribution of the wild tetraploid emmer wheat Triticum turgidum subsp. dicoccoides (=Triticum dicoccoides) and Timopheev’s wheat Triticum timopheevi subsp. araraticum (=Triticum araraticum; Zohary, Hopf, and Weiss 2011).View Large ImageDownload PowerPointAt first, molecular studies placed a probable single origin of emmer wheat in Turkey. Özkan and colleagues (Özkan et al. 2002; Salamini et al. 2002) examined 204 AFLP loci of 99 wild emmer lines from all over the Fertile Crescent belt and several dozen different cultivars. They concluded that the most likely place of origin for emmer wheat is the Karacadağ Mountains in southeastern Turkey. There is, however, still a debate regarding the validity of these results and the number of possible domestication events as attested by recent molecular studies (e.g., Brown et al. 2009; Feldman and Kislev 2007). As Feldman and Kislev (2007) pointed out recently, the data of Mori et al. (2003), Özkan et al. (2002, 2005), and Luo et al. (2007) may indicate a diphyletic or polyphyletic origin of domesticated emmer, possibly in the Karacadağ area, as well as in the southern Levant.ArchaeobotanyHulled emmer wheat. The earliest fully convincing sign to date of domesticated emmer comes from the numerous spikelet forks retrieved from EPPNB, ca. 10,600–9900 cal BP, Çayönü (van Zeist and de Roller 1991–1992, 2003). Here, hundreds of spikelet forks were discovered, all showing rough breakage scars characteristic of domestic emmer. Numerous spikelet forks, with similar telltale rough scars, are also available from contemporary contexts at Cafer Höyük (de Moulins 1997). These finds indicate that at EPPNB, emmer domestication must have been well under way in the Fertile Crescent. We wish to have more data before being fully convinced about the domestication status of the EPPNB Cypriot find from Kissonerga-Mylouthkia and Shillourokambos (Murray 2003; Willcox 2000).To date, the earliest conspicuous grain-size increase is reported from EPPNB Tell Aswad, near Damascus, Syria (van Zeist and Bakker-Heeres 1982 [1985]). Here dicoccum-like plump kernels start to appear in the lowest habitation level, Ia (ca. 10,500–10,200 cal BP; Willcox 2005), and also in MPPNB phases II (ca. 10,200–9550 cal BP). In these phases, however, no rachis segments have been retrieved. Significantly, no wild dicoccoides-like narrow kernels were retrieved from Tell Aswad. As van Zeist and Bakker-Heeres emphasize, the continuous presence of morphologically discernible dicoccum kernels, the total absence (from the very start) of dicoccoides-like material, and the extreme dryness (less than 200 mm annual rainfall) suggest that emmer wheat was introduced into the Damascus Basin as a domesticated cereal not later than the second half of the eleventh millennium BP. From ca. 10,100–8700 cal BP onward, charred grains that morphologically conform with dicoccum appear also at Tell Abu Hureyra, northeast Syria, again with no rachis segments (Hillman 1975, 2000; Hillman, Colledge, and Harris 1989), and in contemporary PPNB Can Hasan III and Çatalhöyük East, Konya plain, Turkey (Fairbairn, Near, and Martinoli 2005; Fairbairn et al. 2002, 2007; Helbaek 1964, 1969; Hillman 1972, 1978), Ali Kosh, Deh Luran Plain, Khuzistan (Helbaek 1969), and Jericho, Israel (Hopf 1983). From the very beginnings of agriculture in Southwest Asia, emmer is one of the principal cereals, and it prevails quantitatively over domesticated barley and domesticated einkorn.Free-threshing emmer wheats. Free-threshing wheat forms, identifiable by their rachis fragments, make their appearance in Southwest Asia soon after the firm establishment of emmer wheat cultivation (for review, see Maier 1996). They are already present among the plant remains of Late Pre-Pottery Neolithic B (LPPNB), ca. 9600–8600 cal BP, Can Hasan III, Turkey (Hillman 1972), and of MPPNB, ca. 10,200–9550 cal BP, Tell Aswad (van Zeist and Bakker-Heeres 1982 [1985]) and LPPNB, ca. 9450–8600 cal BP, Tell Bouqras (van Zeist and Waterbolk-van Rooijen 1985), Syria. They also occur in the MPPNB/LPPNB, ca. 9300–9000 cal BP, Çatalhöyük, Turkey (Fairbairn, Near, and Martinoli 2005; Fairbairn et al. 2002; Helbaek 1964), and Tell Ramad, Syria (van Zeist and Bakker-Heeres 1982 [1985]).Barley Hordeum vulgareBiologyDomesticated barley Hordeum vulgare subsp. vulgare is one of the main cereals of the belt of Mediterranean agriculture and a founder crop of Old World Neolithic food production. All over this area barley is a common companion of wheat, but in comparison with the latter, it is regarded as an inferior staple. Yet barley withstands drier and warmer environments, poorer soils, and some salinity. Because of these qualities, it has been the principal grain produced in numerous areas and an important element of the human diet. Barley is also the main cereal used for beer fermentation in the Old World. The crop was and still is a most important feed supplement for domestic animals.Barley is a diploid (2n=2x=14 chromosomes) and predominantly self-pollinated crop. All cultivars have nonbrittle ears, a sharp contrast with wild barleys, in which ears are always brittle. Nonbrittleness in domesticated barley is governed by a recessive mutation in either one of two tightly linked “brittle” genes (Table 3).Barley ears have a unique structure. They contain triplets of spikelets arranged alternately on the rachis. According to the morphology of the spikelets, domestic barley can be divided into two principal types.1. Two-rowed forms, traditionally called Hordeum distichum, in which only the median spikelet in each triplet is fertile and usually armed with a prominent awn. The two lateral spikelets are reduced and are grainless and awnless. Each ear thus contains only two rows of fertile spikelets.2. Six-rowed forms, traditionally called Hordeum hexastichum, in which the three spikelets in each triplet bear seed and usually all are awned. Ears in these varieties therefore have six rows of fertile spikelets.Wild barley is spread over the East Mediterranean Basin and the West Asiatic countries (fig. 4), penetrating as far as Turkmenia, Afghanistan, Ladakh, and Tibet. Wild barley occupies both primary and segetal human-made habitats. Its distribution center lies in the Fertile Crescent. In this area, wild barley is continuously and massively distributed. It constitutes an important annual component of open herbaceous formations, and it is particularly common in the summer-dry deciduous oak park-forest belt east, north, and west of the Syrian Desert and the Euphrates Basin and on the slopes facing the Jordan Rift Valley. From here, it spills over the drier steppes and semideserts.Figure 4. Distribution of wild barley Hordeum vulgare subsp. spontaneum (=Hordeum spontaneum). The area in which wild barley is massively spread is shaded. Dots represent additional sites mainly of weedy forms. Wild barley extends eastward beyond the boundaries of this map as far as Tibet (Zohary, Hopf, and Weiss 2011).View Large ImageDownload PowerPointThe origins of barley are still not fully understood. Early crossing experiments and chloroplast DNA (cpDNA) typing have suggested that barley is of one, two, or at most a very few major domestication events (Zohary 1999). Later, Badr et al. (2000) examined 400 AFLP loci in wild and domesticated lines and found that barley is probably of a monophyletic origin in the Israel-Jordan area. However, in recent studies that included sequencing of seven genetic loci, Morell and Clegg (2007; as well as other molecular studies by Molina-Cano et al. [2005], [Saisho and Puruggana 2007], and Wang, Yu, and Ding [2009]) suggested two origins: one within the Fertile Crescent and a second farther east, possibly at the eastern edge of the Iranian Plateau. Apparently, European and North African barley is largely connected to the Fertile Crescent, while much of Asian barley is connected to the eastern center.ArchaeobotanyUnmistakable remains of nonbrittle barley (i.e., forms that could survive only under domestication) came from phase II (ca. 10,200–9550 cal BP) in Tell Aswad (van Zeist and Bakker-Heeres 1982 [1985]) and from ca. 9450 to 9300 cal BP Jarmo, Iraq. In the latter site (Braidwood 1960; Helbaek 1959a, 1960, 1966), Helbaek was the first to show two-rowed barley remains still closely resembling wild spontaneum but also displaying a nonbrittle rachis. Similar finds were reported and verified by Hopf (1983) in PPN Jericho. Indicative clues come from ca. 9600–8750 cal BP Ali Kosh (Helbaek 1969), where the brittle spontaneum-like material characterized the lower layers, and in the upper strata it was replaced by nonbrittle broad-seeded barley forms. Hulled barley has been found in Cyprus from the EPPNB, ca. 10,650–9550 cal BP (Murray 2003; Willcox 2000).Domesticated barley continued to be a principal grain crop in Southwest Asia throughout the Neolithic period. Its remains have been recovered side by side with wheats in most Neolithic sites. Shortly afterward, we are faced with more advanced forms (i.e., six-rowed hulled as well as naked cultivars of barley).In conclusion, the archaeological finds indicate that barley is a founder crop of the Levantine Neolithic agriculture and a close companion of emmer and einkorn wheats. The archaeological remains make it also possible to trace the main developments of barley under domestication: first the fixation of nonbrittle mutations and subsequently the emergence of six-rowed hulled and naked types.PulsesLentil Lens culinarisBiologyLentil ranks among the oldest and the most-appreciated grain legumes of the Old World (Smartt 1990; Zohary 1995). In Mediterranean agriculture it is a characteristic companion of wheat and barley. Compared with the cereals, yields are relatively low, but lentil stands out as one of the most nutritious and tasty pulses. The protein content is about 25%, and lentil constitutes an important meat substitute in peasant communities.The domesticated crop Lens culinaris (=syn. L. culinaris subsp. culinaris; Lens esculenta) manifests a wide range of morphological variation in both its vegetative parts and its reproductive parts. Like many other annual grain crops, lentil is predominantly self-pollinated, diploid (2n=2x=14), and interfertile, or largely so.Conventionally, lentil cultivars are grouped in two intergrading clusters of seed sizes: (a) small-seeded lentils (subsp. microsperma), with small pods and small 3–6-mm seeds, and (b) large-seeded
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