The Skull of Quadruped and Bipedal Vertebrates. Djillali Hadjouis

saved from the fire that targeted the destruction of the Arabic manuscripts stored in the Spanish monastery of El Escorial in 1671, Ibn al-Awam, a famous Sevillian Arab agronomist of the 12th century, describes his agronomical work. Dozens of pages are devoted to the horse alone, considered an animal with unequalled virtues. He describes, in addition to the way of treating the sick animal, the ways of riding a horse, with or without weapons (Clément-Mullet 2000).

      In the 19th century, the unpublished sum of documents on horse riding and hippology gathered by General Daumas (1803–1871) in the book The Horses of the Sahara illustrates the relations that the Arabs had with the horse, its breeding, its education, the care to be given to it and the thousand ways of using it (Pouillon 2008).

2.2. The donkey (Equus asinus)

      Order Perissodactyla Owen, 1848.

      Family Equidae Gray, 1821.

      Genus Equus Linnaeus, 1758.

      Species Equus asinus Linnaeus, 1758 (African wild donkey).

2.2.1. Chronological, geographical and morphological indications of species

      Two subspecies of wild donkey are known in Africa and particularly in North Africa: the Nubian wild ass, Equus asinus africanus (or Equus africanus africanus), native to Nubia, Sudan and Eritrea, and the Somali wild ass, Equus asinus somaliensis (or somalicus). The Somali wild ass is said to be the origin of all domestic forms; it is recognizable by the transverse stripes on its legs. However, while the interspecific distinction is biologically clear-cut, stating that donkeys belong to a species distinct from hemiones, zebras and horses, the complexity seems great when distinguishing between current domesticated donkeys and their ancestors (Groves 1966; Eisenmann 1995). According to Groves (1966, 1986), neither the Nubian nor the Somali wild ass appear to be good candidates for the role of ancestors to the domesticated donkeys and do not constitute homogenous groups, judging by their outward appearance. In general, zoologists distinguish wild donkeys by, among other things, their colors: the wild Nubian form is grayish or gray, without dark markings on the limbs, the Somali form is reddish fawn, the shoulder stripe is poorly defined or absent, and the limbs are marked with dark transverse stripes (Dorst and Dandelot 1976).

      To this must be added a possible third subspecies of wild donkey, recognized on the rock walls of Algeria (Camps 1984).

The domesticated donkey is smaller than the horse, has long ears, a heavy, upright head, a poorly developed mane, and the hair is formed only by a small cluster extremity (Barone 1976; Figure 2.7). The frontal bone is distinguished from that of the horse by its proportionally larger zygomatic process, and the supraorbital edge is also more prominent above the orbit than in the horse. The parietal bone, which has the same disposition as the horse, is traversed by a temporal line interrupted by a more or less wide groove that separates it from the external sagittal ridge. This characteristic does not always exist in the horse (Barone 1976).

      An asinian species (Equus melkiensis) was first described in 1983 by Bagtache et al. at the Aterian Warthog site in Algiers (Algeria), later found at other sites in Morocco. Melki’s donkey is the largest and the most robust of the asinian species in Africa: its size varies between 1.35 m and 1.40 m at the withers. The morphological characteristics of the teeth and their occlusal pattern are similar to those of the asinian species, while one of the dental characteristics (typical stenonian pattern and relatively symmetrical double-loop) is found in species other than donkeys, particularly in hemiones.

Figure 2.7. Head and body quadruped posture of the African wild ass (© Hadjouis and Le Bihan)

      It has been found in the typical Warthog deposit, in the deposit of karst cracks in the Filfila massif, in the Aïn-Benian cave (Bagtache and Hadjouis 1983; Bagtache et al. 1984), in Columnata (Chaïd-Saoudi 1984) and in Morocco (Sidi Bou Knadel and El Mughara El Aliya (Zouhri and Aouragh 1997)). For Eisenmann (1995), some of Tighennif’s metapodes could be related to this same species, making E. melkiensis the oldest asinian in Africa, known only in North Africa. This hypothesis seems difficult to accept when we know that all dental material is attributable to the zebra E. mauritanicus alone. Furthermore, we remain attached to the idea that phylogenetic relations could exist between E. melkiensis and Equus tabeti of the Ain Hanech (Hadjouis 2001). Recent research on donkeys in Africa suggests that genomic analyses are indispensable for a better ancestral identification of the fossilized Asinian taxa as well as for their descendants (Youcef 2018, 2020).

      2.2.2. The status of the donkey over the centuries

      According to popular tradition, if the donkey is humble, the horse is proud, because of its humility, hard work, obedience and patience. But most often it has been designated, first by the Fathers of the medieval church, as a symbol of ignorance, stupidity, stubbornness, laziness and lechery, to such an extent that the image has been assigned to man (Duchet Suchaux and Pastoureau 2002).