But if the thought of organic robots is strange enough, things got really weird with the next generation.

“If I took all the parts of your car and hooked them randomly to one another, you’d expect it would be bad,” says Blackiston. “But it turns out biology has a lot more flexibility than that.” Xenobots 2.0 were formed from stem cells extracted from frog embryos and allowed to develop without relying on the algorithm. Independently, the cells began to develop entirely novel body plans. Hair-like motile cilia grew all over their surfaces – a feature usually found in the lungs, but these cilia were more like limbs, flailing rapidly to allow the xenobot to swim through its environment. In this video, a xenobot navigates a pretzel-shaped maze without touching the sides.

Rather than building a tadpole, the stem cells responded to the unique conditions of the laboratory environment to build bodies totally unlike their amphibian origins. They self-assembled spontaneously, leap-frogging (as it were) evolution.