From frogs: engineers first created work from living cells

     The robot is an artificial body of living cells that can be controlled.

     Robots made of skin and heart cells taken from frog embryos were assembled into stable forms, designed by a supercomputer and placed in a petri dish. The skin cells give the body a shape that resembles a drop with four “legs”, while the cells of the heart pump blood inside the organisms and help them move.

     Each robot has a length of about 1 mm. Scientists have called the development “xenobots” – in honor of the frogs of the species Xenopus laevis, embryonic cells which formed the basis of the devices.

     Tests have shown that organisms are able to swim inside the fluid from a few days to a few weeks, working only on the accumulated germ energy. In groups, they usually swam in circles and could even push pellets into the center of the tank inside which they moved.