What Makes a Rabbit Cute? Preference for Rabbit Faces Differs according to Skull Morphology and Demographic Factors

SIMPLE SUMMARY: The majority of pet rabbits have flatter, shorter faces than wild rabbits. However, rabbits with flat faces are at higher risk of developing considerable health problems, including painful dental problems. The aim of this research was to identify which type of rabbit face people actually prefer, in order to better understand why rabbits with flat faces might be bred and purchased. Images of 25 rabbit faces were assigned to a face-type group by 134 veterinary professionals. Through an online questionnaire, people then rated each of the 25 images according to preference for the rabbits’ faces, and a total of 20,858 questionnaires were completed globally. Through statistical modelling, we show for the first time that mildly flat-faced rabbits (on a scale of extremely flat-faced to extremely long-faced) are more preferred globally than any other kind, and that the longest faced rabbits are the least preferred. Aside from the shape, other features of rabbit faces that were preferred include a soft, medium-light fur appearance and being generally short-furred. These results support the theory that the human preference for the baby-like features of flat-faced rabbits has driven their popularity. We would encourage breeders to avoid breeding extremely flat-faced rabbits due to the associated health problems and to focus instead on breeding more preferred mildly flat-faced, erect-eared rabbits such as the Havana breed. ABSTRACT: Domesticated rabbits typically exhibit shorter, flatter skulls than their wild counterparts (brachycephalism). However, brachycephaly is associated with considerable health problems, including problems with dentition. The aim of this study was to establish which type of rabbit face people prefer, with a particular emphasis on skull morphology and brachycephaly. We grouped 25 images of rabbit faces by cephalic degree based on ratings assigned by 134 veterinary professionals. An online questionnaire was then launched, in which people could rate each of the 25 images according to preference for the rabbits’ faces, and a total of 20,858 questionnaires were completed globally. Repeated-measure, multi-level general linear modelling revealed mildly-brachycephalic rabbits to be the most preferred type of rabbit, and moderately-dolichocephalic (longer skulled) rabbits to be the least preferred. The preference for brachycephalic rabbits was stable across continents, and as such it is highly plausible that human preference has been a driver for the shortening of the skull typically seen in domestic rabbits, perhaps as a result of the ‘baby-schema’. Additional features of rabbit faces that were preferred include a soft, medium-light fur appearance and being generally short-furred. These novel insights may prove useful in the improvement of the public understanding of rabbit health and welfare. The relationship between preference and skull shape is particularly pertinent to future work concerning rabbit health, given the cross-species evidence that having a flat face is associated with chronic health conditions.