Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Caterpillar vs Butterfly DNA
Name: Anonymous
Status: Other
Age: 30s
Location: N/A
Country: N/A
Date: August 2002

How does the DNA of a caterpillar compare with the DNA of the butterfly/moth that it eventually becomes ? eg. If you were to genetically fingerprint both forms, would they be the same or different ?

If they are different, how different ? - and how does the restructuring occur? If they are the same, how do they have such different morphology/behaviour etc. ?

The DNA of any organism is the same in every cell of its body except in its eggs or sperm, which have half the amount. The DNA in your toe cells is the same DNA that is in your stomach cells. So the caterpillar and the butterfly cells have the same DNA. The cells have the ability to turn genes on and off at different stages in their life cycle. So the caterpillar is using its caterpillar genes and the butterfly is using its butterfly genes. When you were an embryo some different genes were functioning than the genes you have now.


Sorry for the delay. The caterpillar and butterfly DNA are the same. The organism contains DNA that encodes for both body forms. During metamorphosis, some new genes are turned on that modify the body shape of the organism and produce the final butterfly body shape. In addition, many of the same genes are expressed in both body forms.

My lab used to work a lot with fruit flies, a similar organism. In the larval stage (the "maggot"), there are tiny pockets of cells set aside very early in development that will give rise to the adult fruit fly structures. During metamorphosis, these pockets of cells grow to form the legs, wings, etc. of the fly, while many of the tissues of the larva decay. Some parts of the larva do not decay, but are modified and reused in the adult. An example would be parts of the nervous system.

Paul Mahoney, PhD

Click here to return to the Molecular Biology Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory