The drop ears gave the RT a loss of erectile power and rounded tips, both areas that should be avoided in the rat terrier. Rose ears are extreamly hard to get rid of. It is this preference that helped shape the rat terrier into a breed of predominately erect ears. Resent results in UKC show rings have substantiated the Erect as Prefered in the rat terrier. Ears are very complex creatures.
Lets think about what actually goes into the making of an ear.
Obviously size and shape. Each of these variables can effect the outcome of the ear. To try to individually control just one of these factors is near impossible. Now Lets take look at the various types of Ears below.then. Notice the shape, nice triangles that are in balance with the head.