they are one of the cats which cannot purr: "in five cat species (lion, tiger, jaguar, leopard and snow leopard) the epihyoideum is an elastic ligament, whereas in all other species of the felidae the epihyal is completely ossified (bony)... those felids with an elastic epihyoid are able to roar but not purr, while species with a completely ossified hyoid are able to purr but not to roar". despite this, it seems now that snow leopards cannot roar, though they can make a number of other sounds.