A lack of locomotor activity rhythms in Drosophila melanogaster larvae (Diptera: Drosophilidae)

We examined the locomotor activity of Drosophila melanogaster for the existence of circadian rhythms, using the wild type and two mutants of the period (per) gene, per super(0) and per super(s). This was accomplished using a newly described apparatus for the recording and measurement of larval path lengths over a 96-h test period. None of the larvae examined exhibited appreciable diel rhythms under cycling conditions of light or temperature. Larvae were also not rhythmic under free-running conditions. Our results suggest that the per gene does not influence an observable locomotor behavioral phenotype in the larval stage of development.