FOLTZ, J.L.; University of Massachusetts at Boston: Respiration and Metabolic Rates in Worker and Queen Carpenter Ants

Despite their ecological importance and interesting social organization, few data exist about the physiological characteristics of ants, especially queens. Because of its relative large size, abundance, and economic importance as a wood-eating pest, we chose to study metabolic rate of the carpetner ant, Camponotus pennsylvanicus. CO₂output of C.pennsylvanicus queens (n=21) and workers (n=65) was measured using flow through respirometry with a LI-COR LI-6262 and recorded with DATACAN V acquisition and analysis software. Body mass varied from 78.6g to 132.1g for queens but was 3.4g to 52.9g for workers. By ANCOVA queens and workers share a common mass scaling of SMR=1520BM^.0857 (SMR is in &microW at 25&degC and BM is measured in grams), a value slightly higher than previously reported for arthropods. Ants exhibited discontinuous ventilation with period between CO₂ release lasting 30 minutes to several hours. It was determined that discontinuous ventilation patterns or interburst interval is significantly affected by temperature. ANCOVA revealed a higher coefficient for queens (interburst int.=17060T^-2.40) than for workers (interburst int.=2972T^-2.40). This study contributes evidence supporting an exponent higher than the .82 found for other arthropods. More significantly, it provides data on the scaling coefficient between two different castes of carpenter ant as well as on the sensitivity of interburst interval during discontinuous ventilation to changes in temperature.