#TIL flatfish have an eye that migrates to the other side of the head after birth. It helps hunting and predator aversion from the ocean floor to have two eyes up. This seems key to epigenetic study by I didn't find multi-generational studies that manipulate environment to see whether the eye migrates even when disadvantageous over multiple generations. Seems to me that the obvious assumption is that we'd find reversibility in this adaptation. And that the calcified institutions would doubt that reflexively.