For flies kept in total darkness, the peak locomotor activity occurs at the same point in circadian time in 2xDpse\per^per.PT D.melanogaster as in D.pseudoobscura. The overall shape of the locomotor activity curve over circadian time for these transgenic D.melanogaster is similar (but not identical) to that for D.pseudoobscura. The circadian mating rhythm of D.melanogaster is altered by the presence of Dpse\per^per.PT : Peak mating occurs at circadian time (CT) 18hours, much later than in wild-type D.melanogaster (CT 9hours), or D.pseudoobscura (CT 12hours), although D.pseudoobscura does have a more minor peak in mating activity at CT 18hours. In a mixed population, progeny resulting from mating between per^+t13.2 carrying flies and Dpse\per^per.PT carrying flies are less common than those between flies carrying the same transgene. (This data is for a population in which males have had there wings removed to eliminate mating song difference as a variable, kept in constant darkness.) 90 minute matings at particular points in the circadian cycle show that this effect is most pronounced at circadian time 12 hours, when the ratio is approximately 5:1 , and is greater than 2:1 at other circadian time points.

Dpse\per^per.PT, per⁰¹ has abnormal locomotor rhythm phenotype