Do they feel pain as we do??

[rjlittlefield]

Regrowth can go wrong:

http://www.zin.ru/animalia/coleoptera/eng/coraeb7.htm

This is called teratology and I once had a specimen with twin tarsi on one leg.

Very interesting link.

This specific example seems like a good example of teratology, but I don't see "regrowth" since those spare legs formed in a single go during pupal development. Or are you thinking about some underlying phenomenon that I've overlooked?

BTW, I had a chance yesterday to review a fascinating project involving chemical stimulation of regrowth and healing in stick insects and flatworms. This was in the senior division of our regional ISEF-affiliated science fair. The student did a really nice job -- he'll go far. (Sell your stock in ginseng; buy grape-seed extract.)

--Rik

[JoanYoung]

Thanks for the interesting link Harold and for everyones comments. Regrowth is a very interesting subject and one wonders why insects and lizards are capable of it but not humans or animals. Has any research been done into our missing link.

[Harold Gough]

Ken,

The image I posted was not necessarily the most representative but it was available and suitable for illustrative purposes. More relevant examples are hidden in journal references which do not offer free access.

I would like to have researched it more but there is too much about teratology of embryonic origin rather from regeneration.

Harold