Figure 5 .

Functional effect of two genetic loci on chromosome 1 ((A)) and chromosome 9 ((B)). The dark period is shaded gray. Both loci appear to have the greatest effect in the high activity periods; there is little difference between the two genotypes in the low activity period concentrated between 8 am and 5 am. The chromosome 1 locus effect is largely between 6 pm and 1 am. The chromosome 9 locus affects activity between 6 pm and 7 am. For both loci there is evidence of the dark cycle nadir shifting a little.