Extended Data Fig. 7: Signs of early asymmetry in the pericardial mesoderm.
a, Reconstruction of the pericardial mesoderm. b, Maps of local deformation distribution resulting from mapping left and right sides of the pericardial mesoderm to each other. Specimens shown are the RSGs from ventral and dorsal views. Dotted magenta line indicates the midplane intersection. The color coding corresponds to the relative levels of morphological variation within each specimen. c, Ventral view of the pericardial mesoderm of RSGs (orange), including the view of the left side flipped with respect to the midplane onto the right side. d, Plot shows the characterization of the misalignment between the two sides of the pericardial mesoderm. A mixed linear model was applied to estimate the asymmetry between both sides at different stages (fixed effects) adjusted by the l distance with two-sided p-value calculation. The schemes on the right show how the l distance was determined. e, Ventral view of the foregut pocket endoderm in the RSGs. f, A similar representation of the foreguts in e, indicating the midplane intersection (pink dotted lines), the ridges detected, first bilateral and later fused medially (blue), and the d1 line, at the border between the myocardium and the splanchnic mesoderm (red). n, normal direction of the midplane.
