Fulani nomads and their genetic relationships to neighboring sedentary populations.
Publication: Human Biology
Publication Date: 01-FEB-06
Delivery: Immediate Online Access
Author: Cmejla, R.
The Fulani (also known as the Foulah, Peulh, Peul, Fulfulde, or Fulbe) are an ethnic group of sub-Saharan Africa who live in 17 states and number almost 30 million people. Although most Fulani now live settled lives, they spring from an originally nomadic population. Both the settled and nomadic communities are collaborating. The settled communities cultivate the cereals (mainly sorghum) and raise a small number of domestic animals; the activities of the pastoral groups are concerned almost exclusively with animal husbandry. It must be stressed that cattle keeping is really the central point of cultural identity of all Fulani nomads. Because of the specific needs of this practice, more pronounced division of labor, resulting in longer time separation of the husband and wife, is encountered in Fulani society. Males deal with the pasture, and females sell milk and milk products in town markets. Nomadic Fulani are known from almost all localities of the West African savanna and the Chad basin.
Archeological indicators date the origin of this nomadic population, on the basis of the rock art of the central Sahara, to about 5,000 years ago (Dupuy 1999); some indicators even suggest a Neolithic origin of the Fulani population (Ba and Dieterlen 1966). Some Fulani groups settled to form a number of important states: the kingdom of Tekrur on the lower Senegal River in the 11th century, the Massina Empire on the middle Niger in the 15th century, and the Sokoto Empire in the 19th century in northern and eastern central Nigeria.
The modern Fulani, who live in sub-Saharan Africa between the Sahara and the tropical rain forests, can be divided into the settled Fulani (15 million people) and the nomadic Fulani (up to 13 million people), sometimes called the M'Bororo (or Bororo) or the Wodaabe. The nomadic Fulani live in the African middle savanna belt, from eastern Senegal to the Central African Republic, and are the most numerous nomadic group in this area. Linguistically, both Fulani groups (the herders and the agriculturalists) belong to the Atlantic branch of the Niger-Congo language family (Ruhlen 1987).
Fulani nomads remain detached from the settled Fulani. Over the course of the year they practice seasonal migration; in the rainy season they move with their herds to the north, and in the dry season they return to the south. The north-south line varies by tribe and family but is generally about 500 km long (Dupire 1962). In addition to these seasonal movements, there is large-scale migration, by which the nomadic Fulani have spread across the West African savanna and the Chad basin (Mohammadou 1975).
From an anthropological perspective the Fulani are rather heterogeneous; they show similarities to other sub-Saharan populations, but some characteristics--such as pale skin, a long, straight nose, and thin lips--link them to North African groups. In the 1930s it was assumed that the Fulani had migrated into the Lake Chad region and further into the West African savanna from East Africa, and even Egyptian and Near Eastern origins were proposed (Tauxier 1937); on the basis of the Rh system, however, it has been possible to link these populations to West African groups (Excoffier et al. 1987).
mtDNA Variability in Sub-Saharan Africa
The mtDNA diversity of African populations is relatively well known, but not all regions and ethnic groups have been sufficiently sampled yet; indeed, the mtDNA data of people from such inaccessible areas as eastern Chad or the Congo basin have not been studied at all.
From the phylogenetic point of view the mtDNA sequences from sub-Saharan Africa have been classified into L-type haplogroups (Chen et al. 1995, 2000; Watson et al. 1996, 1997; Rando et al. 1998; Bandelt et al. 2001; Pereira et al. 2001; Torroni et al. 2001; Brehm et al. 2002). About 30 sub-Saharan L-type haplogroups have been identified, and their ethnic or geographic origins and coalescence times have recently been summarized (Salas et al. 2002, 2004; Kivisild et al. 2004; Rosa et al. 2004). It seems that the main diversifications originated in East Africa but that the West African regions also contributed to the recent, wide mtDNA diversity.
The nomadic Fulani have not been studied with regard to mtDNA so far. The only samples (n = 61) from a Fulani-speaking population have been presented in research by Watson et al. (1996, 1997), who investigated a mixed sample of settled Fulani from Cameroon, Niger, and Nigeria. Close relationships to the neighboring settled populations of West Africa (the Tuareg, Kanuri, Hausa, Songhai, Yoruba, and Mandenka) have been confirmed by other studies [e.g., Pereira et al. (2001) and Salas et al. (2002)]. This Fulani group cannot be separated from the other populations, even by the indexes of molecular diversity (Pereira et al. 2001; Trovoada et al. 2004). Rosa et al. (2004) has recently studied another group of sedentary Fulani (n = 77); these are Fulani from Guinea-Bissau, unique in their slight divergence from six otherwise similar populations in Guinea-Bissau. Their haplogroup profile shows high proportions of haplogroups Lib, L2a, and L3b in particular, although a few Eurasian haplogroups were also found among them.
The aim of this study is to present the HVS-I mtDNA sequences of nomadic Fulani groups from four different locations that have not yet been described in this way. There are four questions that we seek to answer: (1) What is the mtDNA profile of the sample--does it include haplogroups of East or of West African origin? (2) Are the sampled Fulani genetically homogeneous, and do they reveal similar degrees of molecular diversity? (3) Are there genetic differences between the nomadic and sedentary Fulani populations? (4) What are the genetic relationships between the Fulani and their neighbors?
Despite the large size of the contemporary nomadic Fulani population (roughly 13 million people), the genetic diversity and degree of differentiation of Fulanis compared to other sub-Saharan populations remain unknown. We sampled four Fulani nomad populations (n = 186) in three countries of sub-Saharan Africa (Chad, Cameroon, and Burkina Faso) and analyzed sequences of the first hypervariable segment of the mitochondrial DNA. Most of the haplotypes belong to haplogroups of West African origin, such as L1b, L3b, L3d, L2b, L2c, and L2d (79.6% in total), which are all well represented in each of the four geographically separated samples. The haplogroups of Western Eurasian origin, such as J1b, U5, H, and V, were also detected but in rather low frequencies (8.1% in total). As in African hunter-gatherers (Pygmies and Khoisan) and some populations from central Tunisia (Kesra and Zriba), three of the Fulani nomad samples do not reveal significant negative values of Fu's selective neutrality test. The multidimensional scaling of FST genetic distances of related sub-Saharan populations and the analysis of molecular variance (AMOVA) show clear and close relationships between all pairs of the four Fulani nomad samples, irrespective of their geographic origin. The only group of nomadic Fulani that manifests some similarities with geographically related agricultural populations (from Guinea-Bissau and Nigeria) comes from Tcheboua in northern Cameroon.