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Name: Liesl
Status: educator
Grade: K-3
Location: Outside U.S.
Country: USA
Date: Spring 2012

Our 2nd grade class is observing the life cycle of what appears to be monarch butterflies unfold. Currently, our little caterpillars appear to be shedding chunks of their bodies. What is happening to them?

The monarchs are molting. Since insects have exoskeletons (skeletons on the outside of the body) they must periodically "shed" to accommodate further growth. These shed exoskeletons are known as exuvia. Each stage in-between a molt is known as an instar. Try to have your students count the number of molts before the caterpillar undergoes metamorphosis.

Dr. Tim Durham Undergraduate Studies & University Colloquium Department of Biological Sciences Florida Gulf Coast University

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