Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. Despite their popularity, for their seemingly helpless-looking eyes and flat faces, short-skulled (or brachycephalic) dogs like the French bulldog often have serious difficulty breathing. A study published today in the journal PLOS One found that in 12 breeds, a flat face, collapsing nostrils, and rounded physique puts them at a higher risk for developing common breathing conditions. Pekingese and Japanese chins were noted to be the highest risk. The study examined the risk of Brachycephalic Obstructive Airway Syndrome (BOAS) in 14 short-skulled dog breeds. Image: Anthony Lewis (www.anthony-lewis.com), PLOS, CC-BY 4.0 For breeds like bulldogs and pugs, their shortened skull shape can lead to a condition called Brachycephalic Obstructive Airway Syndrome (BOAS). It causes exercise intolerance, difficulty breathing, and wheezing and can lead to surgery. Pugs, French bulldogs, and bulldogs are the most well-known and studied brachycephalic breeds, but there are several other dog breeds that could face these same issues.  “BOAS exists on a spectrum. Some dogs are …