Entropy estimation in Muscina stabulans (Fallen) (Diptera, Muscidae) under laboratory conditions

Entropy (H) as a concept in demography was adapted from that of physics to quantify the impact of mortality on life expectancy and to quantitatively demonstrate mortality tendencies in experimental populations. Entropy was estimated for 160 pairs of Muscina stabulans (Fallen, 1817) in a climate-controlled chamber (24.8 degree C plus or minus 0.6 degree C, relative humidity 70 - 80%, 12 h photophase). Both sexes had H values intermediate to those theoretically expected (0.0 - 0.5), showing that the survival curve is rectangular. The age-specific mortality distribution shows that mortality affects adults of this species in two ways. First, mortality is higher for 10 days from pupal emergence. Second, mortality again increases between 20-30 days after emergence. Small differences in mortality rates cause a greater overall impact on the survival of females.