A blonde is driving through Texas when her car breaks down. Luckily, an indian riding a horse passes her, so she stops him and asks him if he could give her a ride to the nearest town.

She climbed up behind him on the horse and they rode off.
The ride was uneventful except that every few minutes the Indian would let out a whoop so loud that it would echo from the surrounding hills.

When they arrived in a town, he let her off at the local service station, yelled one final, “Yahoo!” and rode off.

“What'd ya do to get that Indian so excited?” asked the service station attendant.

“Nothing,” shrugged the woman, “I merely sat behind him on the horse, put my arms around his waist, and held onto his saddle horn so I wouldn't fall off.”

“Lady,” the attendant said, “Indians ride bareback...”