Space travel shortens diapause in gypsy moth eggs

Field-collected and laboratory-reared gypsy moth eggs were exposed to microgravity, cosmic radiation, sub-freezing temperatures, unusual vibrations, and other extraterrestrial phenomena while they were sealed for 6 days, in January, in a Get-Away-Special (GAS) canister in the open bay of a NASA earth-orbiting spacecraft, the Columbia. Insects were not exposed to light after preparation for and during space flight. Under field conditions, out-of-doors, the eggs should have hatched in April, after 3-4 months of chilling temperatures and should not have hatched after the 6 days of chilling to -11 degrees C during flight in the Columbia spacecraft. However by April 1, more than 4000 larvae had hatched from eggs that had travelled in space, as opposed to approximately 350 from a similar number of control, earthbound eggs. These results indicate that the period of a circannual rhythm in field- and lab-reared insects had been shortened, presumably as result of exposure to microgravity, other factors associated with space flight, and/or conditions of outer space. These results suggest that it may be possible to develop methods for rearing the gypsy moth year round, without the necessity of three months chilling interspersed in the development process. This, in turn, would facilitate production of large numbers of insects for sterile male release or for use as a rearing medium for parasites, predators and pathogens of the gypsy moth.