Meeting Abstract

P3.117  Jan. 6  Detailed analyses of metabolic rates during larval development in Manduca sexta BOYLAN, AC*; MELBARDE, A; STEARNS, MH; VREEDE, AP; HARTLAUB, BA; GILLEN, CM; ITAGAKI, H; Kenyon College; Kenyon College; Kenyon College; Kenyon College; Kenyon College; Kenyon College; Kenyon College itagaki@kenyon.edu

Investigations of body size and metabolic rates in organisms typically involve different individuals of different species. Using the larvae of the moth Manduca sexta, we have measured the metabolic rates of identified individuals throughout their larval development, during which they increase in weight by 4 orders of magnitude. Our results and analyses so far indicate that the slope of the log metabolic rate vs. log body weight relationship varied over the 5 instars of development, with the 4th instar having the lowest value (0.704) while the 5th instar had the highest (0.991); over all the instars, the slope coefficient was 0.803. The distribution of the slope coefficients and the intercepts were approximately normal with the 3rd instar showing the lowest variation in the metabolic rate data. Bootstrapping methods were used to compare investigators, experimental set-ups, and years in which the data were collected. No significant effects were found for these factors. Power calculations show that practical differences in the slope coefficients will be detected. For example, the chance of detecting a difference of 0.045 is over 95% based on our data from 2005 and 2006. (Supported by the Kenyon Summer Science Scholar Fellowships.)