Introduction The purpose of this lab was to observe the life cycle of the V. cardui--a common type of butterfly with thirty day lifespan--but mostly to analyze the transfer of energy from a trophic level to another and compare the actual results to the “10% rule.” Also, I did this lab in order to find the energy efficiency and compare the rate of mass loss of larvae and control cup. I investigated this by measuring the changes in mass in larvae and food over time. Then, I would find the differences of mass every day to see if the rate of mass loss is faster in larvae or control cup. Also, to see the changes in V. cardui, I took notes on the changes every day. To observe the efficiency and the “10% rule,” I measured the mass of chrysalises …show more content…
If we do not have a control, we do not know if the loss of food in the larvae cup is caused by the larvae’s consumption of the food or evaporation of the water in the food. #2 They were subtracted so that if the decrease in mass in food is faster with larvae or not. Also, we want to remove the lurking variable, which is the evaporation of water that causes an increased rate of decrease in mass in food. #3 The graph shows the cumulative mass loss of control and larvae cups. Overall, the graph indicates that the cumulative mass loss has been always greater in larvae cups than in control cups. This indicates that the mass loss in larvae cup is caused by the evaporation of water in food as well as larvae’s consumption of food. #4 The curve is somewhat bell-shaped. This is because the larvae have been actively consuming food until it has become a chrysalis. When it has become a chrysalis, the “larvae” is not consuming food anymore. At the end, the rate of mass decrease become faster in control daily mass loss, shown in a negative value at the end of the graph (faster evaporation). The date the larvae become a chrysalis is also indicated in the observation