Treatments with Wnt agonists induce changes on the A/P polarity of developing buds. Ventral views of B. schlosseri colonies (oozoids) incubated with 0.5 μM APL (top row), and control colonies incubated with DMSO (bottom row). The antero/posterior (A/P) axis of zooid (light blue), primary bud (dark blue), and secondary bud (yellow) are represented in both samples. (A-B) During the first few days of treatments, no major signs of axis alteration of budlets (arrows) are visible. (C) Starting from the second blastogenic cycle (N + 1, stage 9/8/3), clear morphological changes are visible throughout the whole animal. Ectopically growing secondary buds (highlighted by white dashed lines) are visible after the first and second blastogenic cycle (days 11 through 16 post incubation) with an altered axis orientation. (D) The heavy pigmentation and the different polarity of the budlets persist even approaching the take-over stage (N + 1, stage 9/8/5). Note that the budlets axes are now almost perpendicular to the axes of the primary buds compared to a parallel disposition of the control. (E) Three weeks later (N + 2, stage 9/8/2), primary buds are difficult to recognize due the massive alteration of the overall morphology whereas no secondary buds were found at this point. Now the heart (h) is centrally located compared to the control in (E’) situated on the left side. (A’ through E’) Control animals incubated with DMSO did not show any A/P polarity alteration throughout the three blastogenic cycles analyzed. BAR: 200 μm.