Ethan  Corey  

EFFECTS OF LIGHT CHANGE ON THE LIFESPAN ON THE VANESSA CARDUI

The Vanessa cardui (Painted Lady Butterfly) that is the butterfly we are focusing on. The butterfly migrates to even Hawaii and Iceland. They prefer brightly light places. After they hatch it takes a few weeks for them to hatch. The warmer it is also makes them grow faster. Their lifespan depends on the climate. Only adults survive in the winter. But they usually never survive more than one. They migrate mainly migrate during the spring and summer and they go north. This information is important because we are testing to change their habitat.

We are studying if the caterpillars survive to the pupation stage in full light and no light. We found in our background research that they survive better in a bright area. And in a hot area. We learned that from our background research. We studied the butterflies and were wondering if the butterfly could survive with light or not. Why are you studying this?

We thought that the ones with no light would survive the best. We thought that because we thought that the constant light might kill the caterpillars. We tested this by putting baby caterpillars in a fume hood and separated them with a broken cardboard box and put a lamp over one of the caterpillar sets.    

CATERPILLAR  

CHRYSALIS  

BUTTERFLY  

EGG  

Ethan  Corey  

 

Materials:

A small paint brush

30 small cups

30 caterpillars

A scale

A lamp

300 grams of Food

2 bins

A fume hood

The sharpie

Thermometer

Cardboard

We first labeled the cups. Then we put 10 grams of food per cup. Then we put the caterpillars inside of the cup with the food using the paintbrush. After, we put the cups in the bins (15 caterpillars per bin) and also put the thermometer in the bin to record the temperature. Then we put the bins in the fume hood. One bin was protected from the light with a piece of cardboard. The other bin had a lamp over it. And we checked the caterpillars every day except on the weekend.

Results:

Days  to  Pupation  CONTROL  GROUP   EXPERAMENTAL  GROUP  

C1  PUPATED  IN  20  DAYS   E1  PUPATED  IN  21  DAYS  C2  PUPATED  IN  20  DAYS   E2  DIED  C3  PUPATED  IN  23  DAYS   E3  DIED  C4  PUPATED  IN  20  DAYS   E4  PUPATED  IN  22  DAYS  C5  PUPATED  IN  22  DAYS   E5  DIED  C6  PUPATED  IN  20  DAYS   E6  DIED  C7  PUPATED  IN  21  DAYS   E7  PUPATED  IN  23  DAYS  C8  PUPATED  IN  21  DAYS   E8  PUPATED  IN  22  DAYS  C9  PUPATED  IN  21  DAYS   E9  PUPATED  IN  23  DAYS    C10  PUPATED  IN  23  DAYS   E10  PUPATED  IN  23  DAYS    C11  PUPATED  IN  22  DAYS   E11  DIED  C12  PUPATED  IN  20  DAYS   E12  PUPATED  IN  22  DAYS  C  13  DIED   E13  DIED  C14  PUPATED  IN  23  DAYS   E14  DIED  

Table  1  

Ethan  Corey  

Table  2  

C15  PUPATED  IN  20  DAYS   E15  DIED  From the control group 14 caterpillars survived, 6 caterpillars survived from the

experimental group. The variance from the control was 1.5 the variance from the experimental was 0.6. Our p value is 0.017 so we can reject the null hypothesis.

Discussion + Conclusion

We were surprised with our results because in our background information it said they survived better in hot weather. We might have used a too powerful lamp and burned the caterpillars. We also might have affected their growth by shacking them too much. We might have had too little samples to test. No one else has tested this experiment. We now have a better understanding of if the caterpillars survive better in full darkness or in complete light. We can actually go into different amounts of light like 0%, 25%, 50%, 75%, and 100% light.

Bibliography: Opler, Paul A. A Field Guide to Eastern Butterflies. Houghton Mifflin Company, 1992.

Sheilds, O. World Distribution of of the Vanessa Cardui group. Journal of the Lepidopterists' Society 46(6):235-238.

Shull, Ernest M.. The Butterflies of Indiana. Indiana Academy of Science, 1987.

Accessed  through:  http://www.biokids.umich.edu/critters/Vanessa_cardui/