Meeting Abstract
The relationship between humans and domestic dogs has dramatically changed in the ~20,000 years since their domestication. In the past 500 years, domestic dogs have increasingly become the focus of intense artificial selection, leading to extreme variation in skull shape. Selection for snout length has been particularly intense, with some dogs having long slender snouts (many sighthounds), and others having almost no snout at all (pugs). This likely has impacts on structures within the snout, such as those related to olfactory ability including the cribriform plate. Using CT scans from over 40 dog breeds, we reconstructed the cribriform plate using Materialise 3-D rendering software and then applied geometric morphometrics to quantify how cribriform plate shape varies among breeds. The overall shape of the cribriform plate across domestic dogs varies greatly, and closely maps the overall shape of the snout. In dog breeds with thin elongate snouts, the cribriform plate is long and narrow, much like a vase, whereas in dogs with shortened snouts, the cribriform plate resembles more of a shallow, broad dish. While dog breeders have not selected for alterations to the shape of the cribriform plate, the intense selection for extreme skull shapes in a relatively short period of time has greatly modified the shape of the cribriform plate.
