"In a study published in Nature Communications, the researchers reveal an elegant molecular mechanism that acts like a GPS coordinate system for regenerating cells… the puzzle was how the cells in the regenerating limb-stump controlled their levels so precisely to know exactly where they were on the axis from shoulder to hand.”
The Nature paper:
Woah, fascinating. Of course very far out, but manipulating and regenerating human limbs in a similar way would be serious sci-fi stuff. Just impressive