“We discovered that features stipulated in the breed standard of the St Bernard became more exaggerated over time as breeders selected dogs that had the desired physical attributes,” said Dr Klingenberg.
“In effect they have applied selection to move the evolutionary process a considerable way forward, providing a unique opportunity to observe sustained evolutionary change under known selective pressures.”
Ref: Drake AG, Klingenberg CP. The pace of morphological change: historical transformation of skull shape in St Bernard dogs. Proc Royal Soc B 2007; DOI 10.1098/rspb.2007.1169 (subscription required)