Fig. 4. Effects of surgery on behaviours elicited by touching the anterior of the body. (A) Behaviours elicited in the three experimental groups by anterior stimulation. Shortening was the most common response in all three groups. Control, N=22; nerve cuts, N=9; neuromeres ablated, N=10. (B) CCA1 behaviour scores. (C) Individual CCA1 scores of leeches in each experimental group. The distribution of scores for `control' leeches and the distribution for `ablated' leeches are farthest apart, and the distribution of scores for `cut' leeches lies between the two. See Table 1 for a description of the behaviours.