At low temperature and in uncrowded culture conditions, rare escaper ik2⁴ adults (<1%) are observed, but they die shortly after eclosion. These escapers often exhibit abnormal bristles, both the interommatidial and the humeral bristles are affected. At high magnification, the actin footprints along the length of the bristle shaft in ik2⁴ escaper adult eyes appears less organised than those in wild-type bristles. In wild-type, interommatidial bristles are found at alternating vertices, whereas in ik2⁴ mutants these bristles are often duplicated at a single vertex and are misshapen and kinked.