Wing Loss Research Articles

Comparison of Genetic Variation in Two Carabid Beetles (Coleoptera) of Differing Vagility

Amount and geographic pattern of genetic variation as measured by horizontal starch-gel electrophoresis are compared in the fully winged Platynus tenuicollis LeConte and the wingless P. angustatus Dejean. P. tenuicollis samples exhibit Wright's F ST values significantly greater than zero at 10 of 19 polymorphic loci, whereas P. angustatus samples have 14 of 20 polymorphic loci with significant F ST values. The clinal transition in allelic frequencies observed across the five P. tenuicollis samples suggests a pattern of steppingstone gene flow, and isolation of populations by distance. Allelic frequencies in five samples of P. angustatus are correlated with altitude. This altitudinal correlation is also observed in beetle morphology, suggesting that variation within P. angustatus is attributable to altitudinally related factors. The erratic gene frequency distribution in this species, and heterozygote deficiency within sample sites, suggests very low levels of gene flow among adjacent populations and inbreeding within populations. Flight wing loss is considered a powerful specialization that can enhance localized adaptation.

Life-lengthening effects of γ-radiation on the adult housefly, Musca domestica

Effects of γ-irradiation on the life span of the adult housefly ( Musca domestica) were examined in order to elucidate the relationship between metabolic rate, irradiation and longevity. Adult houseflies of both sexes, exposed to 0, 20, 40 and 66 kR of γ-radiation, were housed under conditions of relatively high or low physical activity. The mean longevity of high activity males exposed to 20 and 40 kR exhibited a significant increase, whereas the average life span of all female populations, low activity males, and high activity males exposed to 66 kR was significantly decreased following irradiation. Radiation exposure caused a reduction in the rate of oxygen consumption in both sexes as well as a decrease in the incidence of wing loss in the male flies. Analysis of the results suggests that radiation-induced life-lengthening in the housefly is a consequence of reduced metabolic activity.

Mating behavior, physical activity and aging in the housefly, Musca domestica

Effects of varying population composition, mating behavior, and physical activity on wing loss, flightlessness, and lifespan of male and female houseflies were studied. The frequency of wing loss and flightlessness increases due to mating activity, whereas lifespan decreases as mating activity increases. Restriction of physical activity and elimination of mating by confining flies individually doubles the mean and maximum lifespans of males. Under conditions of similar physical activity, mean and maximum lifespans of males and females become equal. Results of this study demonstrate that aging in the housefly is greatly influenced by physical activity. It is postulated that the generally observed differences in longevity of male and female flies may not be genetically determined.

Duration and frequency of wing beat in the aging house fly, Musca domestica L.

1. The age-related changes in wing beat frequency and duration of flight were studied in senescent male and female NAIDM house flies.2. The average wing beat frequency increases to a maximum by the fifth day in female and by the fourth day in male house flies.3. Duration of flight shows a steady, day-to-day decline with age. In females, this falls from 500 minutes for one-day-old to 110 minutes for 22-day-old flies. For males, this drop is more striking, with duration of flight falling from 420 minutes in one-day-old to 63 miiutes for nine-day-old males.4. These findings correspond to and confirm quantitatively previously reported data for wing loss and similar age-related changes in enzyme and coenzyme content in the flight muscle of senescent house flies.