Radiation exposure causes developmental alterations in size and shape of wings and structures associated with song production in male crickets (Acheta domesticus)

Environmental disasters and growth of nuclear power contribute to increasing levels of radiation pollution in the biosphere. Major impacts concern development, fertility, and survivorship in diverse species. Subtle impacts are less appreciated even though they may have profound effects on individuals and populations. Here, we examined radiation impacts on male crickets, Acheta domesticus (L.) (Orthoptera: Gryllidae), specific to wing development. Alterations in global wing morphology are detectable, but this is a flightless species. However, mating success of males is highly dependent on specialized courtship songs generated by structures associated with the opposing forewings. Such signals identify males as both conspecific and 'attractive/fit' mates. Highly specialized structures found on male forewings include the chord, harp, mirror, plectrum, and file. These work in concert to generate the species-specific male courtship song. Even slight alterations in wing morphology can alter these signals, and variation may also vary acoustic signals among populations. Here, we analyze the impacts of early-life radiation exposure (0-10 Gy) on male forewing shape and size using morphometric analysis. A canonical variate analysis (CVA) illustrated that wing shape was significantly altered in a dose-dependent basis: 10 Gy (P<0.0001), 7 Gy (P<0.0001), and 2 Gy (P = 0.0001). Principal component (PC) analysis as well as the CVA indicated that most variation in wing structure was associated with the mirror, one of the two main resonating regions on the forewing. Analysis of centroid size found significant reductions with 7 and 10 Gy radiation exposures. Significant radiation-induced increases in fluctuating asymmetry were also detected, with fluctuating asymmetry values increasing with dose. Due to the known specialized nature of song-producing structures and its association with both courtship songs and mating, it is likely that the alterations observed in shape and size will have larger impacts on male reproductive success. We are currently quantifying this and analyzing recordings of song structure to detect and characterize specific alterations by radiation.

Automated summary

Environmental disasters and the growth of nuclear power contribute to increasing levels of radiation pollution in the biosphere, impacting the development, fertility, and survivorship of diverse species. Even subtle alterations in wing morphology of male crickets due to radiation exposure can have significant effects on their reproductive success, particularly through changes in their courtship songs and mating behaviors.