Fig. S1

Development of pelvic fins of zebrafish and Nile tilapia. (A-H) Zebrafish larvae (A-F) and adult (G–H). (A) 8.1-mm TL (total length). (B) Detail of pelvic fin region in (A), showing no evidence of pelvic fin bud (open arrowheads). (C) 8.8-mm TL. (D) Detail of pelvic fin region in (C), showing pelvic fin bud outgrowth in the abdominal position (arrowheads). (E-H) Hematoxylin-stained zebrafish larvae (9.0 mm TL; E, F) and adult (29 mm TL; G, H). (F, H) Details of pelvic fin region in (E) and (G), respectively. Note that pelvic fin muscles (outlined) are attached to the 8th-9th segments. (I-P) Nile tilapia larvae (I-N) and adult (O-P). (I-L) Scanning micrographs of Nile tilapia larvae. (I) Stage 22, 9 dpf. (J) Details of pelvic fin region in (I). (K) Stage 25, 11 dpf. (L) Details of pelvic fin region in (K). (M-P) Hematoxylin-stained Nile tilapia larvae (10 dpf; M-N) and adult (5 months post-fertilization; O-P). (N, P) Details of pelvic fin region in (M) and (O), respectively. Note that pelvic fin muscles (outlined) are attached to the 3rd-4th segments. Arrowheads indicate developing pelvic fin bud. Numbers in the panels indicate the segmental order. Note that larval pelvic fin buds appear in the prospective position of pelvic fins. af, anal fin; df, dorsal fin; cf, caudal fin; pec, pectoral fin; pel, pelvic fin. Scale bars: 1.0 mm for panels (A), (C), (E), (G), (I), (K), (M), and (O); 100 μm for panels (B), (D), (J), and (L); 500 μm for panels (F), (H), and (N); 1.0 cm for a panel (P).