Under ideal growth conditions, homozygotes develop into morphologically normal adults with profound behavioural deficits. Mutant males rarely successfully mate with wild-type females. When presented with wild-type or Adar^- females, mutant males do not initiate any displays of courtship. Homozygous females can be mated by wild-type males and give rise to morphologically normal hemizygous males which show the mutant adult behavioural defects. Mutant adults show severe neuro-behavioural phenotypes. They show uncoordinated locomotion, occasional tremors and varying degrees of abnormal body posture immediately upon eclosion. Mutant adults spend an inordinate amount of time grooming compared to wild type. This obsessive cleaning is apparent throughout the lifetime of the animal. Mutants are capable of flying and jumping but do so only when repeatedly provoked and then only rarely. Flight in these animals is erratic. Flies recover more slowly from ether anesthesia. They show a strong temperature-dependent of behavioural defects resulting in bouts of paralysis and extreme motor uncoordination at the restrictive temperature. The behavioural phenotypes become more severe with age and some new phenotypes appear. Tremors increase dramatically such that locomotion is severely compromised in animals beyond day 50. Animals fall over and become increasingly inefficient at righting themselves. Many animals beyond day 30 show circling behaviour that varies from wide circling to circling while standing in place. A majority of animals beyond day 50 show a persistent upheld wing phenotype. Marked asymmetries appear in the animals, manifesting as one upheld wing or leg, extension of one or both back legs and more severe asymmetries in posture.