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Article
Open Access
Published: 07 June 2023
Northwest African Neolithic initiated by migrants from Iberia and Levant
Abstract
In northwestern Africa, lifestyle transitioned from foraging to food production around 7,400 years ago but what sparked that change remains unclear. Archaeological data support conflicting views: (1) that migrant European Neolithic farmers brought the new way of life to North Africa1,2,3 or (2) that local hunter-gatherers adopted technological innovations4,5. The latter view is also supported by archaeogenetic data6. Here we fill key chronological and archaeogenetic gaps for the Maghreb, from Epipalaeolithic to Middle Neolithic, by sequencing the genomes of nine individuals (to between 45.8- and 0.2-fold genome coverage). Notably, we trace 8,000 years of population continuity and isolation from the Upper Palaeolithic, via the Epipaleolithic, to some Maghrebi Neolithic farming groups. However, remains from the earliest Neolithic contexts showed mostly European Neolithic ancestry. We suggest that farming was introduced by European migrants and was then rapidly adopted by local groups. During the Middle Neolithic a new ancestry from the Levant appears in the Maghreb, coinciding with the arrival of pastoralism in the region, and all three ancestries blend together during the Late Neolithic. Our results show ancestry shifts in the Neolithization of northwestern Africa that probably mirrored a heterogeneous economic and cultural landscape, in a more multifaceted process than observed in other regions.
Main
North Africa’s geographic location, centred between the vast Saharan desert, the fertile Near East and Mediterranean Europe, has resulted in a complex human history in the area7,8. The fossil record suggests long-term hominid and human presence9, although continuity over the past 100,000 years cannot be deduced due to the fragmented nature of the record. In the Late Pleistocene, 15,000 years ago, the remains of foragers excavated in Morocco show a distinct genetic make-up intermediate between contemporary Levantine foragers and sub-Saharan African populations10. Current-day North Africans are largely related to Eurasian populations, which was probably caused by ‘back-to-Africa’ migrations7.
Both archaeological records and archaeogenomic data show that Neolithic farmers (genetically distinct from European foragers) dispersed from the northern Levant and Anatolia to the Mediterranean islands, Italian peninsula and Iberia11,12,13,14,15,16,17,18. Mediterranean coastal routes have long been recognized in the archaeological record as an important part of the Neolithic expansion in Europe. In the western Mediterranean, Impressed Ware technology—and further the Cardial Horizon—spread along the European mainland coast and islands to reach the Iberian peninsula, where both phenomena are present at 7,550 calibrated years before the present (cal BP) (refs. 19,20).
Whereas some studies support a simultaneous appearance of the Neolithic in northwestern Africa (Eastern Rif, Ifri Oudadane site) and Iberia around 7,550 cal BP (ref. 21), the earliest evidence for pottery, domestic cereals and husbandry is found in northern Morocco approximately two centuries later at Kaf Taht el-Ghar (KTG) around 7,350 cal BP (refs. 2,3,22,23). Although Early Neolithic material culture and the first domestic mammals and pulses suggest a connection to Iberia1,2,3, the extent and legacy of these connections remain unclear. However, the first genomic analysis of Early Neolithic farmers from northwestern Africa (from the site Ifri n’Amr o’Moussa (IAM) in central Morocco) shows no traces of admixture with European Neolithic farmers. Instead, it shows long-term population continuity since the Upper Palaeolithic in the region6. This result aligns with the hypothesis that the Neolithic transition in northwestern Africa was initiated by local Epipalaeolithic communities adopting technological innovations4,5, such as those found at IAM: impressed Cardial-like ceramics, similar to those present throughout the western Mediterranean Neolithic Europe, and domestic cereals (for example, a grain of Hordeum vulgare dated around 7,050 cal BP)2. This pattern implies a Neolithization process that contrasts markedly with that of Europe, where it has been established that agriculture was introduced by the west- and northward demic diffusion of Anatolian early farmers11,12. The local development, or acculturation, of the North African Neolithic is further supported by signs of increasingly sedentary Epipalaeolithic groups developing strategies for resource management, such as the exploitation of wild plants and pottery1,4,24,25,26. Rapid climatic changes favoured mobile herding27 and, whereas it has been hypothesized that cattle were independently domesticated in the Sahara28, radiocarbon data suggest a gradual introduction of pastoralism in the Sahara in a southwestwards direction 7,000–6,000 cal BP, possibly from the Near East29,30.
Whereas palaeogenomic studies on the European Mediterranean Neolithic transition are abundant15,31,32,33, North Africa has been the focus of only a single study that generated human genetic data from one Early and one Late Neolithic site6, leaving substantial gaps in the chronology of events. It is evident that the site of IAM shows a Neolithic lifestyle and an absence of European Neolithic ancestry, but whether this was an independent development or the inspiration came from other groups in northwestern Africa or across the Mediterranean Sea remains unclear. Hence, the timeline and processes involved in the Neolithization of the region, the nature and dynamics of different economies in North Africa and the role they may have played in the broader European Neolithic remain understudied and controversial.
In this study we investigate a time series of human remains from four archaeological sites spanning the Epipalaeolithic to Middle Neolithic in current-day Morocco: the Epipalaeolithic site of Ifri Ouberrid (OUB), the Early Neolithic sites of IAM and KTG and the Middle Neolithic cemetery of Skhirat-Rouazi (SKH), co-analysed with previously published genetic data from that region6,10. By sequencing the genomes of nine individuals excavated from these four archaeological sites, we can demonstrate that the Neolithic transition in northwestern Africa was ignited by migration of Neolithic farmers from Mediterranean Europe.
We generated genomic sequence data from nine ancient individuals from modern-day Morocco (Table 1), ranging in genome coverage from 45.75- to 0.017-fold, including five individuals with more than onefold coverage and three with more than ninefold. Chronologically the data span more than 1,000 years, covering the Late Epipaleolithic (n = 1), Early Neolithic (n = 5) and Middle Neolithic (n = 3). Two Early Neolithic sites were studied—KTG (n = 4) and IAM—where we co-analysed the newly generated genomic data of one individual and those previously reported6 (Fig. 1a,b). DNA libraries were generated from DNA extracts obtained from bones and teeth and subsequently shotgun sequenced on an Illumina platform. All libraries presented the degradation patterns expected from ancient DNA, including short fragment sizes and cytosine deamination at read ends (Supplementary Fig. 1). Contamination estimates were generally low for both the nuclear genome and mitochondria except for individual skh003, which showed 10–16% nuclear contamination (Table 1). To assess the relationship of the ancient northwestern African individuals to other ancient and present-day West Eurasian and African populations, we co-analysed our data with relevant ancient (Supplementary Data 2) and current-day groups from Africa, the Middle East and Europe34.
www.nature.com/articles/s41586-023-06166-6
Open Access
Published: 07 June 2023
Northwest African Neolithic initiated by migrants from Iberia and Levant
Abstract
In northwestern Africa, lifestyle transitioned from foraging to food production around 7,400 years ago but what sparked that change remains unclear. Archaeological data support conflicting views: (1) that migrant European Neolithic farmers brought the new way of life to North Africa1,2,3 or (2) that local hunter-gatherers adopted technological innovations4,5. The latter view is also supported by archaeogenetic data6. Here we fill key chronological and archaeogenetic gaps for the Maghreb, from Epipalaeolithic to Middle Neolithic, by sequencing the genomes of nine individuals (to between 45.8- and 0.2-fold genome coverage). Notably, we trace 8,000 years of population continuity and isolation from the Upper Palaeolithic, via the Epipaleolithic, to some Maghrebi Neolithic farming groups. However, remains from the earliest Neolithic contexts showed mostly European Neolithic ancestry. We suggest that farming was introduced by European migrants and was then rapidly adopted by local groups. During the Middle Neolithic a new ancestry from the Levant appears in the Maghreb, coinciding with the arrival of pastoralism in the region, and all three ancestries blend together during the Late Neolithic. Our results show ancestry shifts in the Neolithization of northwestern Africa that probably mirrored a heterogeneous economic and cultural landscape, in a more multifaceted process than observed in other regions.
Main
North Africa’s geographic location, centred between the vast Saharan desert, the fertile Near East and Mediterranean Europe, has resulted in a complex human history in the area7,8. The fossil record suggests long-term hominid and human presence9, although continuity over the past 100,000 years cannot be deduced due to the fragmented nature of the record. In the Late Pleistocene, 15,000 years ago, the remains of foragers excavated in Morocco show a distinct genetic make-up intermediate between contemporary Levantine foragers and sub-Saharan African populations10. Current-day North Africans are largely related to Eurasian populations, which was probably caused by ‘back-to-Africa’ migrations7.
Both archaeological records and archaeogenomic data show that Neolithic farmers (genetically distinct from European foragers) dispersed from the northern Levant and Anatolia to the Mediterranean islands, Italian peninsula and Iberia11,12,13,14,15,16,17,18. Mediterranean coastal routes have long been recognized in the archaeological record as an important part of the Neolithic expansion in Europe. In the western Mediterranean, Impressed Ware technology—and further the Cardial Horizon—spread along the European mainland coast and islands to reach the Iberian peninsula, where both phenomena are present at 7,550 calibrated years before the present (cal BP) (refs. 19,20).
Whereas some studies support a simultaneous appearance of the Neolithic in northwestern Africa (Eastern Rif, Ifri Oudadane site) and Iberia around 7,550 cal BP (ref. 21), the earliest evidence for pottery, domestic cereals and husbandry is found in northern Morocco approximately two centuries later at Kaf Taht el-Ghar (KTG) around 7,350 cal BP (refs. 2,3,22,23). Although Early Neolithic material culture and the first domestic mammals and pulses suggest a connection to Iberia1,2,3, the extent and legacy of these connections remain unclear. However, the first genomic analysis of Early Neolithic farmers from northwestern Africa (from the site Ifri n’Amr o’Moussa (IAM) in central Morocco) shows no traces of admixture with European Neolithic farmers. Instead, it shows long-term population continuity since the Upper Palaeolithic in the region6. This result aligns with the hypothesis that the Neolithic transition in northwestern Africa was initiated by local Epipalaeolithic communities adopting technological innovations4,5, such as those found at IAM: impressed Cardial-like ceramics, similar to those present throughout the western Mediterranean Neolithic Europe, and domestic cereals (for example, a grain of Hordeum vulgare dated around 7,050 cal BP)2. This pattern implies a Neolithization process that contrasts markedly with that of Europe, where it has been established that agriculture was introduced by the west- and northward demic diffusion of Anatolian early farmers11,12. The local development, or acculturation, of the North African Neolithic is further supported by signs of increasingly sedentary Epipalaeolithic groups developing strategies for resource management, such as the exploitation of wild plants and pottery1,4,24,25,26. Rapid climatic changes favoured mobile herding27 and, whereas it has been hypothesized that cattle were independently domesticated in the Sahara28, radiocarbon data suggest a gradual introduction of pastoralism in the Sahara in a southwestwards direction 7,000–6,000 cal BP, possibly from the Near East29,30.
Whereas palaeogenomic studies on the European Mediterranean Neolithic transition are abundant15,31,32,33, North Africa has been the focus of only a single study that generated human genetic data from one Early and one Late Neolithic site6, leaving substantial gaps in the chronology of events. It is evident that the site of IAM shows a Neolithic lifestyle and an absence of European Neolithic ancestry, but whether this was an independent development or the inspiration came from other groups in northwestern Africa or across the Mediterranean Sea remains unclear. Hence, the timeline and processes involved in the Neolithization of the region, the nature and dynamics of different economies in North Africa and the role they may have played in the broader European Neolithic remain understudied and controversial.
Table 1 Summary information of archaeological and newly generated genomic data from the ancient individuals reported in this study
From: Northwest African Neolithic initiated by migrants from Iberia and Levant
Individual
Archaeological site
Archaeological association
cal BP 94.5%
Genome coverage
mt Coverage
Sex
mt Haplogroup
Y haplogroup
Autosomal contamination (%)
oub002
OUB
Epipalaeolithic
7660–7506
45.760
2853.42000
XX
U6a6b
–
1.0440
ktg001
KTG
Early Neolithic Cardial
7423–7267
0.0170
1110.31000
XY
U6
a
0
ktg004
KTG
Early Neolithic Cardial
7159–6945
9.020
2819.18000
XY
HV0 + 195
G2a2b2a1a1c1a
2.0035
ktg005
KTG
Early Neolithic Cardial
7429–7285
1.740
988.41400
XX
U5b2b1a
–
1.7870
ktg006
KTG
Early Neolithic Cardial
7247–6995
1.300
253.99100
XY
J1c3j
G2a2b2a1a1c1a
0.5980
iam004
(IAM.1b)
IAM
Early Neolithic
6894–6679b
0.270
8.92969
XX
U6a7
–
0
skh001
SKH
Middle Neolithic
6437–6295
9.180
492.87900
XX
M1a1b
–
2.5360
skh002
SKH
Middle Neolithic
6733–6500
0.960
64.96840
XY
J2a2d
T1a1a
2.0610
skh003
SKH
Middle Neolithic
6298–6121
0.086
20.69170
XY
U6c
T1a1a
10.8400
The summary includes archaeological site names, chronological archaeological association, radiocarbon dating estimates (cal BP), average genome coverage, average mitochondrial (mt) genome coverage, mt and Y chromosome haplogroups and contamination estimates based on autosomes. Calibrated dates from atmospheric curve IntCal20 (ref. 41).
aInsufficient coverage. bIndividual previously reported and radiocarbon dated in ref. 6.
In this study we investigate a time series of human remains from four archaeological sites spanning the Epipalaeolithic to Middle Neolithic in current-day Morocco: the Epipalaeolithic site of Ifri Ouberrid (OUB), the Early Neolithic sites of IAM and KTG and the Middle Neolithic cemetery of Skhirat-Rouazi (SKH), co-analysed with previously published genetic data from that region6,10. By sequencing the genomes of nine individuals excavated from these four archaeological sites, we can demonstrate that the Neolithic transition in northwestern Africa was ignited by migration of Neolithic farmers from Mediterranean Europe.
We generated genomic sequence data from nine ancient individuals from modern-day Morocco (Table 1), ranging in genome coverage from 45.75- to 0.017-fold, including five individuals with more than onefold coverage and three with more than ninefold. Chronologically the data span more than 1,000 years, covering the Late Epipaleolithic (n = 1), Early Neolithic (n = 5) and Middle Neolithic (n = 3). Two Early Neolithic sites were studied—KTG (n = 4) and IAM—where we co-analysed the newly generated genomic data of one individual and those previously reported6 (Fig. 1a,b). DNA libraries were generated from DNA extracts obtained from bones and teeth and subsequently shotgun sequenced on an Illumina platform. All libraries presented the degradation patterns expected from ancient DNA, including short fragment sizes and cytosine deamination at read ends (Supplementary Fig. 1). Contamination estimates were generally low for both the nuclear genome and mitochondria except for individual skh003, which showed 10–16% nuclear contamination (Table 1). To assess the relationship of the ancient northwestern African individuals to other ancient and present-day West Eurasian and African populations, we co-analysed our data with relevant ancient (Supplementary Data 2) and current-day groups from Africa, the Middle East and Europe34.
www.nature.com/articles/s41586-023-06166-6