Figure 2. Developmental defects observed in two interspecific crosses between D. melanogaster and D. santomea.

In crosses of wild-type D. melanogaster females and D. santomea males, the majority of females (X^mel/X^san) emerge as adults. Those that fail to hatch from embryogenesis manifest cuticular defects typified by (A). Hybrid male embryos (X^mel/Y^san) from this cross usually die and show severe abdominal ablations (B). In crosses between D. melanogaster C(1)RM ♀ and D. santomea ♂, the majority of hybrid females embryos (X^melX^mel/Y^san) fail to hatch and show abdominal ablations (C), while hybrid males (X^san/0) usually survive. Those that fail to hatch are typified by (D).