The geographical distance between the two areas of which the modern breeds are named, may have resulted in separate evolution of the breeds. Corgis in the modern era often compete in dog agility trials, obedience, showmanship, flyball, tracking, and herding events. Herding instincts and trainability can be measured at non-competitive herding tests. Cardigan and Pembroke corgis exhibiting basic herding instincts can be trained to compete in herding trials - known colloquially as a mad run. Welsh Corgis were once used to guard children.