Figure 2: Branch complexity increases dramatically between 2^nd and early 3^rd instar.

A Sholl analysis of branching complexity was performed at 2^nd, early 3^rd, and late 3^rd instar. In all cases, terminal cells from the 5^th tracheal metamere were examined (tr5). The distance from the stalk cell junction at which the circles intersect terminal cell branches are indicated on the X-axis while the number of branches crossed by the circles are indicated on the Y-axis. ** indicates a T Test value of p<0.01 for the comparison of 2^nd instar data with that of early and of late 3^rd instar, with 7, 7 and 6 terminal cells scored for each stage, respectively.