In contrast to wild-type, gl¹ mutants fail to exhibit any light-dependent temperature preference.

Wild-type larvae reduce their path lengths when exposed to light. This response is severely reduced in gl¹ larvae. Wild-type larvae show increased head swinging when exposed to light. This response is abolished in gl¹ larvae. Wild-type larvae show a greater change in direction when lights are turned on or off (light (L) to dark (D), or D to L transition) than in the absence of a light transition (D to D). The amplitude of change of direction is greater for the D to L than for the L to D transition. This difference in the amplitude of change of direction between the D to L and L to D transitions is abolished in gl¹ larvae, although change of direction in the absence of a light transition (D to D) is still significantly lower than for either the D to L and L to D transition.

Newly fertilised homozygous females elicit as much courtship from wild-type males as do newly fertilised wild-type females. Newly fertilised homozygous females extrude their ovipositors at a much lower frequency than control females.

Displays locomotor activity rhythm with an approximately 24h period.

Photoreceptor axons project to the brain aberrantly in late third instar larvae. This phenotype is variable. There is a variable pattern of S phase cells located between the outer proliferative centre and inner proliferative centre, in the region where the lamina precursor cells normally reside.

strength: moderate