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Name: Judy H.
Status: educator
Age: 50s
Location: N/A
Country: N/A
Date: Tuesday, August 06, 2002

How do I explain for preschool the transformation from caterpillar to butterfly?

Good question, Judy! I have worked on insect metamorphosis as an adult scientist, but I well remember how thoroughly confusing I found the concept as a child (long after preschool!). You might try an analogy: Consider humans. Men and boys have the same DNA, but look different, as do women and girls. A boy has the same DNA (I guess you could say "instructions" or something to preschoolers) as he will have as an adult, but a young boy cannot grow a beard. Likewise, a girl will develop a different body shape as she grows up. In both cases, the information was there, but part of it was not used until the organism got older. In humans, the changes occur gradually, while in butterflies, the changes occur more suddenly, while the caterpillar is safely tucked away in the cocoon. What is more, while humans just gradually change their bodies, caterpillars "throw out" a large part of their old body, and use the information they have had since birth to build a new one. That is why caterpillars and butterflies look so different from each other.

Good luck! That is a tall order for preschoolers!

Paul Mahoney, PhD

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