Some of the bristlecone trees twist and others don't.  This is an example of one that doesn't have a spiraling form.  Remember that these trees can easily have 40 annual growth rings per cm. (100 per inch).  Think of how old some of these branches must be.  I don't have any specific idea how old these trees are, but "old, old, old" probably suffices.  You can see the Discovery Trail in the lower right of the picture.