Fig. 4. Development times of progeny from adult flies exposed to constant (A) and transient temperature treatments (B). Included in B are control flies held at constant 25°C for the duration of the experiment (circles, thin solid line), flies that experienced 25°C except for 1 day at 18°C (squares, dot-dash line) or 29°C (triangles, dotted line) or 3 days at 18°C (diamonds, broken line). P values from Kruskal–Wallis rank sum tests are shown below plot B; values in bold are significant at P=0.05 level.