Tracker

So the cowboys hire a native american tracker. The tracker would often dismount his horse, look closely at the ground, sniff, put his ears on the ground, etc. So today they are riding a trail. Tracker asks for a halt, gets off the horse and holds his ears to the ground. Gets up says "Buffalo come!" Cowboy says "Wow! You can feel the vibrations of the herd moving?" Tracker : "No. Face sticky!"