January 20, 2003
From: V. Patel
Sea slugs are considered to the most remarkable example of self mutilation and I would be very grateful if you could recommend any usuful literature.
Dear V. Patel,
'Self-mutilation' is a peculiarly human activity. By definition it requires a knowledge of 'self' and is a prpduct of a very troubled mind. Many animals however, have evolved the ability to drop or break off parts of their body, but as their bodies are designed to do this, I hardly think we should call it 'mutilation'. I remember many years ago there was a controversy in New Zealand about whether it was cruel to cut the tails off living crayfish [lobsters]. The Minister of Fisheries got up in Parliament and said we, and presumably the lobsters, had nothing to worry about, as his experts had told him that joint-legged animals like crayfish had evolved to drop off limbs like this in a process called autonomy and it didn't hurt them a bit!
The process is called autotomy, not autonomy, and although the lizard's tail is an example of it, the poor lobster's tail is not. Have a look at the autotomy page on the Forum for some opisthobranch examples. Not all peculiarities in body shape are the result of autotomy. Have a look at the Abnormalities page for a growing list of strange abnormalities caused by accidental damage or developmental problems.