On the Surface: Studying the Effects of Surface Area to Volume Ratio on Heat Retention for the Madagascar Hissing Cockroach.

Abstract

Madagascar Hissing Cockroaches are small ectotherms that comfortably live in warm environments. Their small bodies developed to live in such environments, but as ectotherms, their bodies will match the temperature of the environment. This begs the question if the cockroaches are able to effectively retain their heat on cooler days and cool off on hotter days. We hypothesized that the bigger cockroaches would be able to retain heat longer than smaller cockroaches because of their higher surface area and volume. In our experiment, we took the dimensions and mass of several cockroaches and made clay models to represent their shapes and mass. In three separate trials, we heated the clay models to 30 degrees Celsius and timed how long it would take for the clay model to reach a resting temperature. In this case, the resting temperature was 25.5 degrees Celsius. At the end of our experiment, we found that the larger clay model retained its heat longer than the smaller clay models, supporting our hypothesis.