| Tail length variation between Mezayen camel breeds. (a) Majaheem camels are characterized by long tails with a narrow tail-base. (b) Shaele, and (c) Waddah camels, which represent the Malaween breeds, display short-tails with wide tail-bases. The white disks on the tail are reference scales (five centimeters in diameter). Images were extracted from Cdrom Archive photos (collected by the authors).

| Tail length variation between Mezayen camel breeds. (a) Majaheem camels are characterized by long tails with a narrow tail-base. (b) Shaele, and (c) Waddah camels, which represent the Malaween breeds, display short-tails with wide tail-bases. The white disks on the tail are reference scales (five centimeters in diameter). Images were extracted from Cdrom Archive photos (collected by the authors).

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Camels are livestock that exhibit unique morphological, biochemical, and behavioral traits, which arose by natural and artificial selection. Investigating the molecular basis of camel traits has been limited by: (1) the absence of a comprehensive record of morphological trait variation (e.g., diseases) and the associated mode of inheritance, (2) th...

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... separation of these two groups is in part based on coat color, but is also based on general features, such as body size, ear length and shape, and tail characteristics (Köhler-Rollefson, 1993;Abdallah and Faye, 2012). Majaheem camels are generally larger, and have long "speared" ears ( Figure 4A), and a long tail with a narrow tail-base (Figure 5a) (Al-Hazmi et al., 1994). On the other hand, all Malaween breeds exhibit comparatively smaller body sizes, have short and tilted ears (Figure 4B), and a short tail with a wide tail- base (Figures 5b-c) (see Supplementary Table S2 for naming details). ...
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... camels are generally larger, and have long "speared" ears ( Figure 4A), and a long tail with a narrow tail-base (Figure 5a) (Al-Hazmi et al., 1994). On the other hand, all Malaween breeds exhibit comparatively smaller body sizes, have short and tilted ears (Figure 4B), and a short tail with a wide tail- base (Figures 5b-c) (see Supplementary Table S2 for naming details). Breeders often do not breed Majaheem camels with any of the Malaween breeds, and when such an event occurs, breeders can easily recognize the hybrid due to changes in body features; such hybrids are often disqualified from competing in beauty competitions (personal observation). ...

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... The natural adaptations of the dromedaries were anthropologically exploited via (1) its domestication around 2000-3000 years B.C., (2) the expansion of their uses, and (3) the development of unique populations (i.e., camel-types) (Uerpmann and Uerpmann, 2002;Almathen et al., 2016;Orlando, 2016). However, unlike other domesticated animals (e.g., cattle, sheep, horses, dogs, and cats), dromedaries do not currently have breed definitions, standards, registries, or breeders' organizations (Arman, 2007;Lynghaug, 2009;Alhaddad and Alhajeri, 2019). Named dromedary populations are locally known and occasionally documented, but little is known about their breed status. ...
... Different dromedary camel-types have been named, yet little or no documentation can be found about their breed status (Arman, 2007;Lynghaug, 2009;Porter et al., 2016;Alhaddad and Alhajeri, 2019). Several camel-type naming systems were previously described such as those based on ecotype (e.g., hill and riverine), country (e.g., Omani and Sudani), region of origin (e.g., Raka and Turkana), tribal affiliation (e.g., Kenani and Borena), and phenotype (e.g., Waddah and Shaele) (Leese, 1927;Mburu et al., 2003;Mehta et al., 2006;Ishag et al., 2010;Mahrous et al., 2011;Porter et al., 2016;Saad et al., 2017). ...
... This is in accordance with previously reported measures of genetic variability reports (Mburu et al., 2003;Legesse et al., 2018). Dromedary camel-types named based on phenotype (e.g., Majaheem, Waddah, and Awadi) are usually selectively bred for distinctive phenotypes (e.g., coat color) (Almathen et al., 2016;Porter et al., 2016;Saad et al., 2017;Alhaddad and Alhajeri, 2019). These camels formed the most homogenous group based on haplotype; with B haplotypes being overrepresented in this group. ...
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