why caterpillars eat their eggshells

[Liz Day]

I had always thought newly-hatched caterpillars (I'm thinking saturniid 
moths, but it could be any lep) ate their eggshells because this provided 
protein.  However, a colleague says they do it to get microbes from the 
parent moth that enable them to digest cellulose.   Only, I didn't think 
caterpillars *did* digest cellulose, I thought they excreted it, but maybe 
I'm wrong on that too.
Please straighten this out.... why DO they eat their eggshells?

Thank you,
Liz

BTW - just got the "Caterpillars of Eastern Forests" book and it's 
terrific!!!   Get one.... so many beautiful photos....

-------------------------------------------------------------
Liz Day
Indianapolis, Indiana, central USA  (40 N, ~86 W)
USDA zone 5b.  Winters ~20F, summers ~85F.  Formerly temperate deciduous 
forest.
daylight at kiva.net
www.kiva.net/~daylight



 
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