Quantum and biological systems are seldom discussed together as they seemingly demand opposing conditions. Life is complex, "hot and wet" whereas quantum objects are small, cold and well controlled. Here, we overcome this barrier with a tardigrade -a microscopic multicellular organism known to tolerate extreme physiochemical conditions via a latent state of life known as cryptobiosis. We observe coupling between the animal in cryptobiosis and a superconducting quantum bit and prepare a highly entangled state between this combined system and another qubit. The tardigrade itself is shown to be entangled with the remaining subsystems. The animal is then observed to return to its active form after 420 hours at sub 10 mK temperatures and pressure of 6 × 10 −6 mbar, setting a new record for the conditions that a complex form of life can survive.

While being a prerequisite for quantum applications, entanglement certification per se destroys the entanglement under investigation. We experimentally certify entanglement without its complete destruction by employing non-projective measurements and subsequently recover the original entanglement.