Posted by Nikita Vikhrev on 27-11-2005 13:52
#10
I have to say, that I absolutly agree with Paul's theory. This theory has all appearence of correct theory, bieng NESSESARY and ENOUGHT.
Otherwise we have the problem to explain not only this Gerard's image, but as well the fact that Dragonflies (very warm-loving group) do not bubling, for example.
Licking-sucking mouseparts in imago and complet reducing mouseparts in larva lead to external digestion in varios ways. So Diptera bubling. Other insecta do not evolve to external digestion and do not bubling.
Nikita