The regeneration of lost body parts is a remarkable biological phenomenon. In general, the tissue left after amputation or autotomy triggers one of two possible responses: scarring against regeneration. Scar formation at the wound site prevents the regeneration reaction, but is by no means understood in terms of evolution. We can assume that scars are a compromise solution that must cope with the development of complex organisms analogous to a frustrated system. Most tissues of higher organisms follow this fate of scars if damaged. This book provides zoology students with a detailed understanding of the autotomy.