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Name: betsy
Status: other
Age: other
Location: MA
Country: N/A
Date: 5/20/2005

Dear Scientist, We have some mail ordered caterpillars in our classroom that came from Insect Lore in CA. They appear healthy, but seem to be producing a web like material. My students are wondering how it is that caterpillars make webs? And why? Do you know the answers to this question?

Caterpillars have spinnerets which produce a silky material. This silk drys when it is exposed to the air. The caterpillars use it to make webs and cocoons. This can be for food, protection, and eventually a safe place to change into a butterfly!

Grace Field

I work with Pieris rapae which is the Cabbage White ("Brassica") butterfly. I don't know what kind of caterpillars you are working with, but brassica butterflies have silk glands in their feet. This helps them to hang on to surfaces. They also use the silk glands to anchor themselves to the spot they will make their crysallis (cocoon, pupa) on.


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