Robotic ray is part animal, part machine

Frankenstein, here we come.

Or Frankenstein's monster if you'd rather.

Or just Frankenstein if you really want to be pedantic.

I caught this video from the Science journal article that goes into more detail than does the above, silent film video (sadly lacking a mustache twirling badguy). In all honesty, the idea of tuning heart cells to contract in response to light stimulus - which is then designed to create waves of motion within the 'string ray' - is pretty phenomenal.