In large chambers, <i>Drosophila</i> prefer egg laying on sugar even when given the option to lay eggs close to the sugar or with diffusion gradients.

<p>In these single island experiments, flies had the options of laying eggs at any location on the substrate. For the purpose of quantification, the petri dish was divided into 7 zones. Relative densities of eggs were calculated for each zone. (A) With 100 mM sucrose island experiments and no diffusion, females laid a significantly greater fraction of eggs in the sucrose island than in any other zone (as determined by a one-way ANOVA and Tukey's Multiple Comparison Test; * indicates p<0.05 as compared to each other zone) (n = 13, average total number of eggs = 24). (B) The island itself was only mildly attractive when filled with plain agarose (no significant differences by one-way ANOVA and Tukey's Multiple Comparison Test) (n = 5, average total number of eggs = 37). (C) In a 100 mM sucrose island with diffusion, females strongly preferred the island as determined by a one-way ANOVA and Tukey's Multiple Comparison Test; * indicates p<0.05 as compared to each other zone; # indicates p<0.05 as compared to zone 3–7) (n = 17, average total number of eggs = 41). (D) A plain island was not attractive in comparison to the sucrose island used in C (̂ indicates p<0.05 as compared to zones 1–4, and 7) (n = 8, average total number of eggs = 15).