Relationship between fluorescent age pigment, physiological age and physical activity in the housefly, Musca...

The objective of this investigation was to examine whether fluorescent age pigment (FAP) was associated with the physiological rather than the chronological age of houseflies (Musca domestica) and to determine if the level of physical activity of individual flies was related to their FAP content. Distinction between the physiological age and the chronological age of the flies was made on the basis of flightlessness which occurs prior to death in all houseflies. Flies with shorter life expectancy become flightless earlier. Walking and flying activity of individual flies was measured by radar-Doppler instrumentation developed in this laboratory. The concentration of FAP, determined by fluorimetry, increased with age but the rate of increase was greater in flightless flies than in their flying cohorts of the same age. FAP content of individual flies tended to be greater in flies exhibiting relatively high levels of physical activity. The results of this study suggest that FAP concentration is associated with life expectancy and physical activity of houseflies.