The rhythmic beating of these clumps is mesmeric—but it could be life-saving, too. These are tiny 3D printed versions of hearts and lungs, which work just like the real thing.
Created by researchers from the Wake Forest Institute for Regenerative Medicine in Winston-Salem, North Carolina, the pale gray objects mimic the heart and the dark one apes the liver. They’re manufactured by “reprogramming human skin cells into heart cells, which were then clumped together in a cell culture,” explains New Scientist. Those clumps were then formed into objected of the desired size and shape using 3D printing techniques, to create cellular blobs that measure just 0.01 of an inch across.