Butterfly Research Project

[Richard Worth]

Hi Kathryn,  Your project sounds great.  You might want to try and 
look up references to Dr. Nihjout's work on development of wing 
patterns during metamorphosis.  If I remember correctly, he used 
buckeyes (Junonia coenia)  which do have eyespots on the forewings. 
You are proposing to use painted ladies (Vanessa cardui)  which don't 
have eyespots on the forewings.  They do have a few small, plain 
white dots on a black background at the tip of the forewing, if 
that's what you are referring to.  Otherwise they are really not 
eye-spotted.  Pricking them might yield some interesting results, 
regardless, as long as it doesn't damage them to the point where they 
lose moisture from within and die.  The terms "pupa" and "chrysalis" 
are really synonymous.  The prof you spoke to probably meant that the 
pupa doesn't harden right away since the tissues underneath the 
caterpillar skin, that are exposed after it molts, are still very 
soft and vulnerable.  The wing area is exposed on the surface.  If 
you are looking at the pupa face-to-face from the underside, the left 
wings will be on the right side.  The wing pads are not very visible 
from the top side since they wrap down and around the body.  The wing 
pattern is only visible about a day or so before the butterfly 
emerges.  You will have to get eggs or caterpillars and raise them 
yourself if you want them to pupate in front of you.  This may take 3 
or 4 weeks or more depending on how much food you can find for them 
in the winter.  The caterpillar will attach itself to a twig or jar 
lid or something with silk and hang upside down to shed its skin.  It 
won't spin a silk cocoon like some moths do.  In the case ofthe 
painted lady, the pupa will often times have a gold sheen to it. 
Very pretty.   I hope this helps and if I can find the actual 
reference to this study I will let you know.  Good luck.
Rich




>    My name is Kathryn McCann and I am a junior at Central Virginia
>Governor's School in Lynchburg, Virginia.  I am planning on doing a research
>project with Painted lady butterflies.  My plan was to prick eyespots on the
>left wings of these butterflies approximately six hours after they pupated.
>This would cause the eyespots to either grow, shrink, or disappear.  The
>right wings would be the controls.  A professor told me that this would be
>possible because the pupae do not form a chrysalis right away and their
>wings are wrapped around the body on the surface and easily accessible.  I'm
>not exactly sure what to expect, though.  Would I be able to tell the left
>wings from the right?  Are the eyespots visible in the pupal stage?  What
>will the pupae look like exactly?  How long will it take them to form a
>chrysalis?  I would really appreciate it if you would answer my questions.
>Thank you so much for your time and help.  My email address is
>kmccann at cvgs.k12.va.us
>Thanks again,
>Kathryn McCann
>
>
>
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Richard A. Worth
Oregon Department of Agriculture
Plant Division
rworth at oda.state.or.us
(503) 986-6461

 
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