Meeting Abstract
Atmospheric oxygen has the potential to affect the physiology, development and evolution of insects. However, insects demonstrate a wide range of responses to variation in developmental, chronic, and acute oxygen exposures. To better understand these differential responses, it is important to consider the life history traits of these organisms. Investment in different life history strategies involves a series of tradeoffs that may make organisms more or less susceptible to atmospheric oxygen. To begin to examine these tradeoffs, a series of experiments have been done that manipulate these life history traits and then measure the responses of those insects to variation in atmospheric oxygen. Manduca sexta lines artificially-selected for high growth rate and large body size were more susceptible to oxygen variation than those selected for smaller body size and slower growth rates. Zophobas morio that were reared individually and experienced faster growth rates were more susceptible to oxygen during the juvenile phase, while those that were reared in crowded conditions and experienced longer development times showed a stronger effect of oxygen on adult lifespan. When comparing Blatella germanica, a small roach species to Gromphadorhina portentosa, one of the largest roach species, G. portentosa showed a larger effect of oxygen on body size, while B. germanica showed a larger effect of oxygen on growth rate suggesting differential energy investment in these two species. In sum, these data suggest that life history traits determine tradeoffs between investment in growth and development and the ability to deal with oxygen stress throughout the lifespan of the organisms.
