The extreme differences in pottery throughout the various Poverty Point territories support the latter view. In order to prevent cracking, some Poverty Point potters added vegetable fibers to the clay; others put sand and grit, bone particles, and hard lumps of clay; others added nothing. Decorations do seem to have followed rather universal styles, but each group of potters seems to have modified them to suit local tastes and to have added new features of their own. Many other tools were used in everyday tasks of building houses, butchering animals and making other tools. We know Poverty Point peoples used stone tools for these jobs and probably also used wood, bone and antler ones, as well. Most of these were very similar to those used by earlier people. Items such as hammerstones, whetstones, polishers, and others, were used mainly in a natural condition and required little or no preparation themselves. The characteristic shapes and signs of alteration that permit them to be recognized today got there through use and not intentional design. Other tools were carefully shaped. Gouges, adzes, axes, and drills fall into this category. The objects were chipped from large pieces of gravel or big flakes into desired shapes. Often polish or tiny grooves appear on the working edges of these tools, which leads us to suspect that they were used to chop and carve wood, dig holes, and drill substances. Some of these items, especially celts and adzes (cutting tools with the blades set at right angles to the handles), have counterparts of ground and polished stone. These smoothed objects were made by chipping, battering, grinding, and polishing in combination or singly. Whether these more elaborate forms were used like their chipped varieties is difficult to say, but they probably were.