(A) Quantitation of survival rates from third instar larvae to adulthood of the indicated genotypes without heat shock (dark blue) or following a 15-min heat shock (light red) (which generates 23% tetraploid, see methods).Bars represent means + standard error of the mean (S.E.M) of at least 5 independent experiments, with 20 animals per experiment. *p<0.05, ***p<0.001, NS = p>0.05, t-test. (B) Representative micrographs of eyes, wings, and abdomens from HS>fzr alone, mad2 alone, or HS>fzr, mad2 flies heat shocked for 15 min as third instar larvae and then allowed to develop to adults. Red arrow indicates an extra ectopic wing vein, and yellow arrow heads indicate melanotic masses both of which are found in in HS>fzr, mad2 adults following heat shock. (C) Representative time-lapse showing a HS>fzr wing imaginal disc 10 hr after a 60-min heat shock including a cell with diplochromosomes (yellow dotted line) and a diploid cell (blue dashed line) dividing within the same field (one of the diploid daughters drifts vertically out of the frame). The cell with diplochromosomes takes more than four times as long to enter anaphase, and division is error prone. His2av-GFP showing DNA is in white. Time indicates minutes from the start of filming. (D) The length of metaphase without fzr overexpression (No HS) or +10 hr after a 60-min heat shock to induce overexpression from HS>fzr, and HS>fzr, mad2 larval wing imaginal disc cells. Points represent individual cell divisions, bars represent means, diploid cells are represented in dark blue, polyploid cells are represented in light red, HS>fzr is represented in circles, HS>fzr, mad2 is represented in triangles. N>17 cells per column, ***p<0.001, Not Significant (NS) = p>0.05, one-way ANOVA with correction for multiple hypothesis testing. (E) Third instar larval wing imaginal discs from HS>fzr or HS>fzr, mad2 stained for TUNEL in green and DAPI in magenta without heat shock (No HS) or +24 hr after a 15-min heat shock. (F) Quantification of the number of TUNEL positive foci per wing disc for HS>fzr and HS>fzr, mad2 without heat shock (No HS, blue bars) or 24 hr after a 15 min heat shock (+HS, red bars). Points represent individual wing imaginal discs, bars represent mean, N ≥ 18 discs per condition. NS = p>0.05, * = p<0.05, *** = p<0.001, ANOVA. Scale bars represent 500 μm in B, 5 μm in C, and 50 μm in E.