We observed severe cardiac edema and reductions in cardiomyocyte cell numbers in the conditional mutant heart at 96 and 120 hpf (Figure 4C–E). The cardiac edema phenotype was not evident or extremely weak at 72 hpf in the conditional mutant heart. We analyzed the global shha mutant embryos at 72 hpf (Figure 3A–C) but not at later time pointes, as proper characterization was nor possible due to developmental abnormalities associated with global inactivation of shha expression. We suspect that inactivation of shha expression in the epicardium leads to heart defects mainly at later developmental stages, and such phenotypes may be obscured in non-conditional mutant embryos by pleiotropic effects of global shha inactivation. We included this interpretation in the revised manuscript as follows: