Paleolithic cave paintings generally use lines to define the contours of animals and other forms. In the case of the paintings in Chauvet Cave (Fig. 1-1, p. 3), lines also seem to serve an expressive purpose, suggesting energy, modeling, and depth. Click the link above to explore how contour lines can be used to define shapes. Find some other examples of art with shapes delineated by contour lines. How does each differ in defining shape and line?