FASCINATING!!!

Thanks Emaline for this fascinating article:

Abstract

Understanding the anatomical and genetic basis of complex phenotypic traits has long been a challenge for biological research. Domestic dogs offer a compelling model as they demonstrate more phenotypic variation than any other vertebrate species. Dogs have been intensely selected for specific traits and abilities, directly or indirectly, over the past 15,000 years since their initial domestication from the gray wolf. Because olfaction plays a central role in critical tasks, such as the detection of drugs, diseases, and explosives, as well as human rescue, we compared relative olfactory capacity across dog breeds and assessed changes to the canine olfactory system to their direct ancestors, wolves, and coyotes. We conducted a cross-disciplinary survey of olfactory anatomy, olfactory receptor (OR) gene variation, and OR gene expression in domestic dogs. Through comparisons to their closest wild canid relatives, the gray wolf and coyote, we show that domestic dogs might have lost functional OR genes commensurate with a documented reduction in nasal morphology as an outcome of the domestication process prior to breed formation. Critically, within domestic dogs alone, we found no genetic or morphological profile shared among functional or genealogical breed groupings, such as scent hounds, that might indicate evidence of any human-directed selection for enhanced olfaction. Instead, our results suggest that superior scent detection dogs likely owe their success to advantageous behavioral traits and training rather than an “olfactory edge” provided by morphology or genes.

Link to full article: https://academic.oup.com/mbe/article/42/3/msaf035/8015493

Interestingly, this is also loosely proven in the AKC obedience and tracking dog titles: most advanced titles are earned by dogs who are known to have “trainability” as a behavioral trait (I believe trainability can be selectively bred for, but I am unaware of research demonstrating that). Before you jump up and say “of course it can be bred for,” recognize the “lore and legend” behind the ‘superior’ scenting skills of the hound group, and bloodhounds in particular—bloodhounds are no more talented in the scenting department than pugs! (FWIW, one of my very first tracking students was a French Bulldog, and Larry was an exemplary tracker….as was my English Bulldog student). However, anecdata/personal experience isn’t data!

I am aware of other studies showing, quite conclusively, that our domestic dogs olfactory skills don’t hold a candle to the skills of coyotes and wolves.

And, yes. This study gives your instructors authority to call you out anytime you suggest your dog’s breed is significant in regards to his tracking prowess.