EvoSheep – Origin and evolution of sheep breeds: The diversity of modern breeds, Ethiopia
EvoSheep is a multidisciplinary project on the origins and evolution of sheep breeds, involving archaeozoologists, epigraphers, bio-statisticians, and geneticists (Vila et al. 2021). The research focuses on the region of sheep domestication in southwest Asia, specifically the Near East, to understand the onset of differentiation of early domestic sheep into multiple breeds. This research is based on the study of archaeological and modern sheep data.
In order to understand the evolution of domestic sheep through time and space and to attempt to relate the past to the present, we investigate modern sheep breeds in a vast region extending from Eastern Africa to Iran. A collection of Awassi sheep skeletons was set up in the Lebanon by an EvoSheep team (see post 2021). Another collection of East African sheep breeds set up in Ethiopia is the subject of this post.
In search of indigenous Ethiopian sheep breeds
Ethiopia, along with Somalia, Eritrea, and Djibouti, is one of the countries making up the Horn of Africa, a large territory bordering the Red Sea. The Horn of Africa has always maintained close contacts with the Arabian Peninsula and the Near East, as the Red Sea has never been an impassable border between the Asian and African continents. This passage has always been used to transport people, domestic animals, raw materials, and manufactured goods between the two worlds. Archaeozoological and genomic research has shown that the first domestic fine-tailed sheep spread from the original Near Eastern domestication area through the Levant and Egypt. On the other hand, the Horn of Africa was a gateway to Bab al-Mandab for the later diffusion of fat-tailed sheep types (Mugai and Hanotte 2013).
Ethiopia is composed of mountainous regions with high plateaus and extremely steep valleys, as well as lowlands. It encompasses diverse environments with various arid, hot temperate, and equatorial climates, and hot to very hot temperatures. This fragmented geography and rugged topography have created isolated enclaves, with a high degree of endemism in regional fauna and flora. In Ethiopia, a wide variety of local or regional hardy sheep breeds are very well adapted to their environments (Gizaw 2009). According to recent molecular studies, nine breeds can be identified (Gizaw et al. 2007). The majority are fat-tailed and fat-rumped sheep (Berhe 2020). Most sheep are short-haired, and those with woolly fleeces are rare. Sheep are mainly bred for meat, hide and skin and milk production. In some regions sheep “are kept mainly as a primary investment and a source of cash in times of need” (Edea 2008). Modern hybridization practices are widely applied throughout the world to improve breeds, but have been very limited so far in Ethiopia. As a result, Ethiopia is particularly suitable for research into sheep types related to the pole of Near Eastern ancestors introduced from the Arabian Peninsula. Building up an osteological collection of traditional indigenous Ethiopian breeds thus provides a complementary reference collection of modern breeds to collections in Southwest Asia, which includes the Awassi sheep in the Lebanon.
With the support of O. Hanotte from the University of Nottingham and the ILRI (International Livestock Research Institute), we organized several field missions to Ethiopia between February 2019 and February 2020 to acquire targeted sheep breed samples and prepare the skeletons. The aim is to obtain reference specimens of several Ethiopian phenotypes. For this, we travelled through much of the country.
The Molale Mountains
The first expedition in February 2019 took us 250 km northeast of Addis Ababa to the Molale Mountains (North Shewa, Amhara region) to look for Menz sheep (Fig. 1).
The Menz breed is a small sheep breed with a wither’s height of around 60 cm and a coarse wool fleece (Mengistu 2008, Berhe 2020). Average adult animal weight is between 22 kg (females) and 25 kg (males). This breed is adapted to cold conditions and high altitudes. These sheep have a short and fat tail, and are medium-sized with semi-pendant ears, but they can also be short or rudimentary (12%). The dominant colors are plain brown, white, and black. Most males have horns, while females generally do not. Menz sheep are kept in small flocks of no more than 30 animals. Meat, manure, and fleece are the main products exploited by pastoralists.
With Adebabay Kebede, a colleague from ILRI, and Michael Temesgen, our driver, we left Addis Ababa early in the morning in a 4×4 car. After a break in Debre Birhan, we continued into the mountains to Molale and the highlands to meet the herders. After a long journey, and the last 50 km on a stony track, in a forest landscape and thick fog, we found the shepherds and their herds on the plateau at an altitude of almost 3000 m (Fig.2 & Fig. 3).
The landscape is hilly and rocky, with areas of open grassland. The dwellings consist of scattered dry-stone houses, traditional houses with wooden and vegetal roofs, and others with metal substitutes. The shepherds had been told of our arrival and had gathered the herds (Fig.4). As we were looking for adult sheep, we examined the teeth, just like shepherds, to estimate the age of individuals. We observed whether the permanent incisors had replaced the pairs of milk incisors to determine whether the animal was adult. On average (but this can vary between breeds), the first pair of incisors (I1) is replaced at about one year of age, the second pair (I2) a little before two years of age, the third (I3) before three years of age; finally the pair of canines is replaced just before 4 years of age (Habermehl 1975; Schmid 1972, Wilson & Durkin 1984). As it is not easy to get a sheep to open its mouth, two people are often required to make these observations in a few seconds (Fig. 5). Finally, we bought three four-to-six-year-old females and two two-year-old adult males and took them back to the Debre Birhan Agricultural Research Center.
At Debre Birhan
The location of the research center where the director kindly allowed us to stay and work is a few kilometers from the town of Debre Birhan. It is a large campus devoted to agronomic research on crops and livestock. It is also an ideal place to prepare the sheep, and a small team of technicians from the center came to help us, with a veterinarian, Derib Aydefruhim (Fig. 6 & Fig. 7). Derib took charge of taking blood for genomic studies, killing the animals, butchering them, and cutting them up. We had to choose the days of slaughter carefully because, in the predominantly orthodox religion in Ethiopia, it is not authorized to eat the meat of an animal slaughtered on a fasting day (Wednesdays and Fridays). We photographed and measured each sheep on its feet, following the protocol used in the Lebanon for Awassi sheep (Fig. 8).
For five days, in a remote area of the campus, we prepared the skeletons in the same way as in the Lebanon, cooking them in large cauldrons over wood fires, paying particular attention to the caudal vertebrae. Then we left the bones to dry in the sun before packing them in plastic boxes and transporting them back to Addis Ababa (Fig. 9 & 10).
We shared the meat among team members. The working atmosphere was friendly; the people of our small team cooperated with each other and worked with good humor and goodwill. We returned to this center in February 2020 to prepare the Afar and Blackhead Somali sheep breeds bought in the sheep markets of Addis Ababa. It was extremely difficult to access the breeding regions of these breeds due to socio-political unrest, so we could not meet the breeders directly in the field. Both breeds are fat-rumped and hairy sheep breeds. Males and females are hornless. The Afar breed comes from the Afar region of eastern Ethiopia, a very arid low-altitude region. The sheep are relatively large: the average height at withers is 63 cm for female adults and 65 cm for males. Afar sheep are generally beige, with a pale-colored belly, a straight profile, and short to rudimentary ears (Mengistu 2008, Gizaw 2009) (Fig. 11). The Black-headed Somali (BHS) breed is widespread in the arid and semi-arid areas of southeast Ethiopia. BHS sheep are characterized by a dark, black, or brown head and neck and a pale white body. They also have a well-developed dewlap, i.e., a fold of skin hanging below the throat (Fig. 12). Average height at withers is 58 cm and the average weight is 27 kg (Bireda et al. 2016).
In Bahr Dar
After Molale and our stay in Debre Birhan, we searched for Washera sheep in the Bahr Dar region, which is next to Lake Tana in northwest Ethiopia (Fig. 13).
Washera sheep are large, measuring around 69 cm at withers (Taye et al. 2010). They are fat-tailed sheep with a slightly hooked nose, a brown coat, and no horns (Fig. 14). Their ears are quite long. They are found in western Ethiopia in the Amhara district in humid and warm regions at altitudes between 1600-2000 m. The weight of an adult female is about 28 kg, and that of an adult male is about 32 kg.
The easiest way to reach Bahr Dar from Addis Ababa is by plane (3/4 of an hour), but part of the team had to travel by car (about 10 hours to cover the 500 km separating the two cities). Bahr Dar is at a lower altitude (1850 m), and is much hotter than Addis Ababa or Debre Birhan. We set out from the city early in the morning to the region of Injibara and the Washera sheep farms of the village of Kosober, a two-hour drive south of Bahr Dar. The hilly landscape consists of open grasslands where donkeys, horses, zebus, and sheep graze freely. Hedges of tree brushwood separate parcels and patches of wooded vegetation. The dwellings are grouped together, made of cob on a wooden frame covered with earth, and thatched roofs can still be seen, but have often been replaced by metal sheet. Washera sheep flocks are small: the average number of sheep per household is about ten heads. Farmers brought us rams, aged from one to two years old, but were not willing to sell us ewes. Prices were very high because the major festive weekend before the Easter festival was coming up, and everyone was looking for meat, especially sheep meat. After long debates, we bought three males but finally returned to the Bahr Dar livestock market to buy two ewes, aged between four and six years old.
We were fortunate to have the support of the Bahir Dar Regional Animal Health Laboratory, a few kilometers from the city, so we moved in with our sheep and prepared the specimens on-site. After photography, measurements, and blood sampling for molecular studies, the sheep were killed and butchered by a professional butcher. Again, the skeletons were prepared by cooking in cauldrons over wood fires following the same procedures as in the Lebanon. We distributed most of the meat to the team. Adebabay also organized a very nice lunch with the employees and the center’s director, and we ate tasty meat cooked with spices in a large pan on a wood fire.
When the Washera sheep skeletons were clean and packed, the car left for Addis Ababa with its precious cargo. Back in Addis, in a green and shady park, we completed the work of marking, measuring, and photographing the bones, specimen by specimen, a task that kept us busy for several days.
Following the same preparation protocols, two further missions by Agraw Amane in spring and autumn 2019 completed the EvoSheep project’s osteological collection with ten specimens of the Bonga breed and ten specimens of the Gumz breed. The Bonga sheep are large with a long fat tail and a hairy coat (Fig.15). They are raised by small holder farmers in Southwest Ethiopia, a hot and humid region (Southern Nations, Nationalities and Peoples region). Sheep are kept mainly as a primary investment and a source of cash in times of need (Edea 2008). They are hornless and have a straight profile. The predominant color is brown; the coat is either plain or tinged with black or white. The average height at withers is 66 cm for females, for a weight of 30 kg; and 68 cm for males, for a weight of 32 kg. The Gumz breed is also a hairy breed adapted to warm environmental conditions and widespread in the lowlands of western and north-western Ethiopia. The tail is long and thin, and the color is plain white or white with brown or black spots (Fig. 16). The profile is convex, and the ears are long. Both males and females are hornless or have rudimentary horns. On average, females weigh 31 kg with a wither’s height of 63 cm and males 35 kg with a wither’s height of 67 cm (Abegaz et al. 2011).
In the end, in the course of this collaborative Ethiopian/French project, we prepared 40 specimens of six different breeds (Menz, Washera, Afar, BSH, Bonga, and Gumz) in the field. We brought the skeletons back to Addis Ababa for study.
Ongoing genetic studies are conducted in Ethiopia at ILRI, and the EvoSheep project morphometric and morphological studies are carried out on the tail in Ethiopia and on the petrous and long limb bones in France (AASPE laboratory and Archéorient laboratory).
These comparative studies will highlight the metric and shape characteristics of these modern breeds. The results will provide a baseline for investigating osteological variations in archaeological assemblages and aim to identify the first clues of race differentiation since domestication.
Our osteological and genetic project also interested a German director, Marvin Enholt, who was preparing a documentary film on sheep (Planet of the sheep, Heidefilm GmBH production, broadcast on ARTE in June 2022). He came to the Debre Birhan agricultural Centre with his team, Johannes Staub, the cameraman, and Ragip Alkan, the soundman, during our last stay in February 2020 (Fig. 17). It was a great opportunity to discuss sheep in the past and in the future with Marvin Enholt and Olivier Hanotte (Fig. 18).
To conclude, this project brought us into contact with very kind people, who contributed to ensuring optimal working conditions. We are indebted to them and have fantastic memories of the time we spent together (Fig. 19 & 20).
We would like to express special thanks to Prof. Olivier Hanotte and Dr. Adebabay Kebede for all the scientific and personal exchanges and support in this work. We wish to acknowledge the staff of the Debre Berhan Agricultural Research Center (especially Dr. Shanbel Besufkad and Mr. Derib Aydefruhim), the Bahir Dar Regional Animal Health Laboratory, Bonga Agricultural Research Center, and Guba & Almeha office of Agriculture for their kind support in sheep skeleton preparation in their respective institutions and farmers` training centers (FTC). We would also like to thank the French Centre for Ethiopian Studies (CFEE) and the Authority for Research and conservation of Cultural Heritage (ARCCH) for their warm welcome in Addis Ababa. Finally, we would like to acknowledge Mr. Michael Temesgen and Anteneh Hailemariam for their kind support and cooperation in providing driving services and their involvement in reference bone sample preparation.
The field data collection (sheep purchase and skeleton collection) was co-financed by the CGIAR Research Program on Livestock (Livestock CRP and the EvoSheep ANR project (France).
EvoSheep is funded by the Agence Nationale de la Recherche (ANR). The project involves the collaboration of five laboratories: Archéorient (Environnements et sociétés de l’Orient ancien, CNRS/ univ. Lyon 2), AASPE (Archéozoologie – Archéobotanique. Sociétés, pratiques et environnements, MNHN/CNRS), CAGT (Centre of Anthropobiology and Genomics of Toulouse, CNRS/univ Toulouse III), LECA (Laboratoire d’Ecologie Alpine, CNRS/Univ. Grenoble Alpes), Smurfit Institute of Genetics (Trinity College, Dublin, Ireland), and multiple archaeologists, statisticians and zoologists, but also the cooperation and help of numerous archaeological missions, heritage institutions or academics and people in the field and in the laboratories.
Abegaz S., Hegde B. P. & Taye M. 2011. Growth and Physical Body Characteristics of Gumuz Sheep under Traditional Management Systems in Amhara Regional State, Ethiopia. Livestock Research for Rural Development, 23(5). http://www.lrrd.org/lrrd23/5/abeg23117.htm
Berhe W. G. 2020. Phenotypic variations of indigenous sheep breed ecotypes of Ethiopia : A review. Journal of Cell and Animal Biology, 14(1), 6-20. https://doi.org/10.5897/JCAB2019.0467
Bireda W., Kebede K., Mekashaw Y. & Bejano S. (2016). Phenotypic Characterization of Black Head Somali Sheep in Gode and Adadile Districts, Ethiopia. Global Veterinaria, 17(3), 265-270.
Edea Z. 2008. Characterization of Bonga and Horro indigenious Sheep breeds of smallholders for designing community based-breeding strategies [Master of Science in Agriculture (Animal Genetics and Breeding)]. Haramaya University.
Gizaw S. 2008. Sheep resources of Ethiopia : Genetic diversity and breeding strategy [Ph.D. thesis]. Wageningen University.
Gizaw S. 2009. Sheep Breeds of Ethiopia: A Guide for Identification and Utilization. In A. Yami, K. Awgichew, T. A. Gipson, & R. C. Merkel (Éds.), Ethiopia Sheep and Goat Productivity Improvement Program (ESGPIP): Vol. Technical Bulletin No.28. ESGPIP. https://docplayer.net/35695156-Technical-bulletin-no-28-sheep-breeds-of-ethiopia-a-guide-for-identification-and-utilization.html
Gizaw S., Van Arendonk J. A. M., Komen H., Windig J. J. & Hanotte O. 2007. Population structure, genetic variation and morphological diversity in indigenous sheep of Ethiopia. Animal Genetics, 38(6), 621-628. https://doi.org/10.1111/j.1365-2052.2007.01659.x
Habermehl K.-H. 1975. Die Altersbestimmung bei Haus- und Labortieren. Parey.
Mengistu T. G. 2008. Characterization of Menz and Afar indigenous sheep breeds of smallhorders and pastoralists for designing community-based breeding strategies in Ethiopia [Master of Science in Agriculture, Animal Genetics and Breeding]. Haramaya University.
Muigai A. W. T. & Hanotte O. 2013. The Origin of African Sheep: Archaeological and Genetic Perspectives. African Archaeological Review 30(1), 39–50. https://doi.org/10.1007/s10437-013-9129-0
Schmid E. 1972. Atlas of animal bones for prehistorians, archaologists and quaternary zoologists / Knochenatlas für Prähistoriker, Archäologen und Quatârgeologen. Elsevier.
Taye M., Abebe G., Gizaw S., Sisay L., Abebe M. & Tibbo M. 2010. Traditional management systems and linear body measurements of Washera sheep in the western highlands of the Amhara National Regional State, Ethiopia. Livestock Research for Rural Development, 22(9).
Vila, E., Abrahami, P., Albesso, M., Amane, A., Bader, C., Berthon, R., Bouzid, S., Bradley, D., Breniquet, C., Chahoud, J., Cucchi, T., Davoudi, H., Cupere, B. de, Escarguel, G., Estrada, O., Gourichon, L., Helmer, D., Huangfu, W., Lesur, J., Mashkour M., Michel C., Mohaseb A., Orlando L., Pompanon F., Studer J., Vuillien, M. (2021). EVOSHEEP: The makeup of sheep breeds in the ancient Near East. Antiquity, 95(379). https://doi.org/10.15184/aqy.2020.247
Wilson R. T. & Durkin J. W. 1984. Age at permanent incisor eruption in indigenous goats and sheep in semi-arid Africa. Livestock Production Science, 11(4), 451-455. https://doi.org/10.1016/0301-6226(84)90056-3
Emmanuelle Vila is a CNRS researcher and zooarchaeologist specialised in south-west Asia. UMR 5133-Archéorient, Maison de l’Orient et de la Méditerranée, Lyon.
Agraw Amane is PhD candidate in Microbial, Cellular and Molecular Biology, Addis Ababa University & PhD graduate fellow at International Livestock Research Institute (ILRI), P.O. 5689, Addis Ababa, Ethiopia.