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qualcosa di interessante da leggere sulle uova di dolabella
There are not many records of predators eating the eggs. As far as I can find, only some starfish and the nudibranch Favorinus japonicus. It has been suggested that the reason animals avoid the eggs as food is because they contain distasteful chemicals, in particular secondary metabolites that they obtain from their algal food. However there have been few staudies on the topic. Pennings (1994) offered pieces of egg mass of Aplysia juliana and Dolabella auricularia to crabs and fish but they were rejected. Organic extracts from the eggs of Stylocheilus striatus [as Stylocheilus longicauda] deterred feeding in reef fish at normal concentrations, but the eggs surprisingly did not contain the expected secondary metaobolites.
In another study, Pennings & Paul (1993) could find no secondary metabolites in the egg masses of Stylocheilus, Dolabella or Aplysia californica after adults were fed on either natural diets or diets containing secondary metabolites.
What then makes the eggs distasteful? It has been suggested that it is perhaps related to algal pigments. The egg colour of Sea Hares depends on the colour of the algae they are eating. For example when a Sea Hare changes from green to red algae its egg colour will chnage (Carefoot 1967). The seaweed pigment is transferrd to eggs within 48hrs (Chapman & Fox, 1969,) It is still not clear whether algal pigments are making the eggs distasteful or whether the Sea Hares are producing a new chemical.
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