Cannibal robots that can grow by feeding on other machines have been built in New York.

Scientists at Columbia University said they have developed a new way for robots to grow, heal, and improve themselves by using parts from their surroundings or other robots.

This process, called 'Robot Metabolism', lets machines absorb and reuse components, moving closer to robots that can take care of themselves.

Lead researcher Philippe Martin Wyder said: 'True autonomy means robots must not only think for themselves but also physically sustain themselves.

'Just as biological life absorbs and integrates resources, these robots grow, adapt, and repair using materials from their environment or from other robots.'

Footage shows this new technology in action using a modular robot called Truss Link, inspired by the Geomag toy.

These robots are made of bar-shaped pieces with magnetic connectors that can join together and move in different shapes.

Professor Hod Lipson, a co-author of the study, said: 'Robot bodies today are monolithic and unrecyclable, unlike biological bodies that grow, heal, and adapt by reusing modules. Robots must learn to use and reuse parts from other robots. This emerging field is machine metabolism.'

Lipson also mentioned that while the idea of self-reproducing robots sounds like science fiction, it is important for robots to learn how to take care of themselves, even if that means using parts from other machines.