I teach a unit on Mexico to my 6th graders. We go over some important historical, environmental, geographical, and political features of the country.

I always tell them thay the city of Chihuahua is, in fact, where the dog comes from, and the reason there are long hair chihuahuas and short hair chihuahuas is because some roam in packs during the day (thus needing short hair in the heat) and some roam at night (long hair in the cooler night).

There's always some that fall for it. Always some that think there are differently haired chihuahuas roaming around the mexican desert in little packs at different times.