Artificial Jellyfish Made From Rat Cells

It looks like a jellyfish. It swims like a jellyfish. But, the tentacled artificial creature above, dubbed the "Medusoid," is actually created by scientists at Caltech and Harvard with rat cells:

It is able to mimic the swimming movement of a jellyfish thanks to muscle cells from rat hearts which were implanted onto its silicon frame and grown into a pattern similar to the muscles of a real jellyfish.
By applying an electric current to a container of conducting liquid, the scientists demonstrated they could "shock" the muscles into contracting so that it began to move through the water.

Nick Collins of The Telegraph has the story: here