Talians have fractal ear lobes.

Talians have fractal ear lobes. Each Talian's ear lobe pattern is unique. Here is a sketch of Bonzi's right ear made when he was born.

Here also is the first paragraph of the book.

"The Fractalians, Talians for short, were a folk who were known by their ears. Their ear lobes were fractal, as was just about everything else in their world. What is a fractal, you ask? Well, for now, let us say it is a pattern that repeats itself as you go smaller and smaller. When a Talian was born the unique pattern on his ear lobes was recorded. You could tell what family a Talian was from by his ears. Talians did not look deep into another’s face or eyes to tell that. They just looked at the ears."