Scientists have managed to build an artificial jelly fish entirely from rat cells, which can pulse and swim when exposed to an electric field, just like its living counterpart.

Taking cells from the heart of a rat, the team of scientists from Harvard University were able to grow a single layer of muscle on top of a patterned sheet of polydimethylsiloxane. The result mimics the bell of a juvenile moon jelly—a type of jelly of fish—which propels itself by sending electric signals through the structure to make it contract rapidly.

When exposed to an electric field, the artificial creature—refereed to as medusoid—contracts rapidly, in the same way as the jellyfish does during its power stroke. The sheet of elastic silicone on which the muscle is built then pulls the medusoid back into shape ready for the next stroke. If you're unconvinced, watch the video above: this thing really does look just like a real jellyfish as it moves through the water. The research is published in Nature Biotechnology. Kit Parker, lead researcher on the project, explained to Nature:


"Morphologically, we've built a jellyfish. Functionally, we've built a jellyfish. Genetically, this thing is a rat... We took a rat apart and rebuilt it as a jellyfish."

When people usually talk about synthetic life, it's at the cellular level. This time round, the scientists have built an actual animal. While it's a pretty cool scientific party trick, the idea is in fact to use the little creatures for testing drugs in the future. And there's more to come, too, because Parker is already planning how to build a synthetic octopus in the same way. Welcome to the future. [Nature Biotechnology via Nature]


Image by Harvard University/Caltech