Table 2.

List of ancient domesticated species in which breeds/varieties with extensive shortening of the snout, i.e., brachycephaly, are known and in which such a phenotype is not just occasionally occurring

Species	Brachycephalic varieties	References
Rabbit	In general, “dwarf rabbits” such as:- Polish- Netherland Dwarf- “Dwarf Rex” (Rexzwerg)- “Dwarf fox” (Fuchszwerg)	this study
Cat	An extensively shortened and dorsally rotated snout, associated with health issues, has mainly been described for two breeds of cats:- Exotic Shorthair- Persian	(Schlueter et al. 2009; Schmidt et al. 2017; Anagrius et al. 2021)
Dog	The following breeds have been described as brachycephalic according to their cranial proportions, dorsal rotation of the snout, and prevalence for diseases associated with brachycephaly and airorhynchy:- Affenpinscher- Border Terrier- Boston Terrier- Boxer- Brussels Griffon- Bulldog- Bullmastiff*- Cavalier King Charles Spaniel- Chihuahua- Dogue de Bordeaux- King Charles Spaniel/English Toy Spaniel- French Bulldog- Japanese Chin- Maltese- Miniature Pinscher- Pekingese- Pomeranian- Pug- Shih Tzu- Staffordshire Bull Terrier- Yorkshire Terrier	(Brehm et al. 1985; Koch et al. 2003, 2012; Schoenebeck et al. 2012; Packer et al. 2015a, 2015b; Marchant et al. 2017)*Unpublished data
Pig	The following varieties/breeds could be categorized as brachycephalic based on the description of their head configuration:- Neijiang: of China. The snout is short and snub-nosed.- Middle White: of England. Extremely short head with strongly dished and “squashed” profile.- Small White (Small Yorkshire): of England, now extinct. This breed's face has been described as very short and extremely dished (even “squashed”), with a broad and up-turned snout.	(Cheng 1985; Porter 1993; Sambraus 2001)
Cattle	Niata (Ñata): from South America, now extinct. Marked shortening and dorsal rotation of the snout relative to the braincase.	(Darwin 1878; Veitschegger et al. 2018)
Goat	Following goat varieties have been described to exhibit a pronounced convex nasal profile, i.e., roman nose. (Note that the presence of a roman nose is also described for other goat varieties, but reportedly not as marked). Additionally, anecdotal evidence suggests that an overshot lower jaw may not be a rare characteristic, although it is defined as an error in some breeding standards. There is probably a connection between the Damascus and the Zairaibi of Upper Egypt and possibly with the Indian dairy breeds.- Anglo-Nubian: English breed, developed mainly from the Jamnapari and the Zairaibi, crossed with European breeds. Today, individuals of this breed may still have the Zairaibi's undershot jaw, but the lower teeth should not be visible.- Beetal: of arid and semiarid Northwestern India. Reminiscent of the Nubian type with roman nose, but not as prominent as in Jamnapari breed.- Bhuj: of Brazil. Similar to the Beetal; mix from Indian breed(s) and Nubian.	(Acharaya 1982; Mason 1984; Porter 1996; Sambraus 2001; Khan and Okeyo 2016)
	- Jamnapari (Etawah): of arid and semiarid Northwestern India. Like the Beetal with a strongly convex profile giving it a “parrot mouth” such as seen in the Anglo-Nubian. One of the largest breeds in India.- Kamori: of Pakistan. With massive head and distinct roman nose.- Shami (Damaskus, Aleppo, Baladi, Damascene): of Syria and Lebanon.- Zairaibi (Egyptian Nubian, Theban): of Egypt. Strongly arched profile with lower lip that often projects beyond the upper, exposing its front teeth (undershot jaw).

Note that due to the difficulties with defining varieties/breeds, intra-breed variation, and variable definitions of brachycephaly, this is not an exhaustive list.