Navajo Rug Weaver

Cartesian Coordinates

 

Another example in which native design is similar to the Cartesian coordinate system is in Yupik parka decoration. According to Claudette Bradley, professor of education at University of Alaska, the Yupik ("YOU-pick" -- one of the groups called "Eskimos") say it is important to have both sides looking exactly the same (reflection symmetry again!).

So they developed a coordinate system, measuring vertical and horizontal distance on the parka using the width of two fingers as the unit of length.

The center of the coordinate system is near the belly button. Why might that be?