Extended Data Figure 7.

Energy landscape of neighbor exchanges. a, Schematic of key cellular configurations throughout a neighbor exchange and associated energy landscape. Changing neighbors requires overcoming an energy barrier. Large enough, active cell-cell contact length fluctuations enable neighbor exchanges. b, Measured energy landscape, E, for PSM and MPZ regions, normalized energy scale E_A associated with cell-cell contact activity or effective temperature energy scale, namely E_A = k_BT_Eff, where k_B is the Boltzmann constant and T_Eff is the effective temperature. n = 6969, 7896 cell-cell contacts obtained from 3, 4 embryos for PSM, MPZ, respectively.