9th December 2023 – (Hong Kong) In a remarkable breakthrough, researchers at Tufts University have created tiny biological robots or “anthrobots” entirely from human cells. These microscopic robots can move, heal wounds, and encourage the growth of neurons, pointing to potential medical applications. However, their creation also prompts fundamental questions about human nature and free will.

Measuring between a human hair’s width to a sharpened pencil’s point, anthrobots are assembled from human tracheal cells without any genetic modification. Tracheal cells normally have hair-like projections called cilia that beat in waves to clear mucus and particles from airways. But when grown in the lab into little spheres called organoids, the cilia spontaneously coordinate to propel the anthrobots across surfaces.

“We wanted to probe what cells can do besides create default features in the body,” explained lead author Gizem Gumuskaya, who has architecture and biology degrees. “By reprogramming interactions between cells, new multicellular structures can be created, analogous to the way stone and brick can be arranged into different structural elements like walls, archways or columns.”

A depth-colored anthrobot is depicted, surrounded by a halo of cilia that enable the bot to move. Credit:  GIZEM GUMUSKAYA, TUFTS UNIVERSITY

Remarkably, the researchers found anthrobots not only formed new shapes but also exhibited purposeful collective behaviours. Clustered anthrobots or “superbots” were able to migrate through scratched “wounds” in neuron cell layers, stimulating regrowth like a living bandage. The anthrobots even encouraged thick bridge-like neuron growth unlike areas without them.

“It is fascinating and completely unexpected that normal patient tracheal cells, without modifying their DNA, can move on their own and encourage neuron growth across a region of damage,” said senior author Michael Levin, director of Tufts’ Allen Discovery Center. “We’re now looking at how the healing mechanism works, and asking what else these constructs can do.”

Beyond regenerative medicine, anthrobots offer safer, less ethically controversial alternatives to embryonic stem cells. They only survive under special lab conditions, naturally biodegrading within weeks. Patient-derived anthrobots also avoid immune rejection, unlike foreign cell sources. The researchers believe they could one day deliver drugs inside bodies or build tissues.

However, the ability to create living machines from human cells blurs the line between technology and biology. If we can design cellular robots, are we just biological automatons ourselves? According to Levin, “The cellular assemblies we construct in the lab can have capabilities that go beyond what they do in the body.” In other words, the anthrobots appear to have functions more programmable than their original purposes in tracheal cilia.

Philosophers have long debated whether humans have free will or if our actions are predetermined by biology, physics, or fate. Neuroscience indicates consciousness emerges from electrical chatter between neurons, suggesting a computational, mechanistic basis beneath our subjective experiences. Observations of automatic bodily processes like digestion that occur without conscious control also illustrate how much of our biology operates involuntarily.

Some scientists propose our feeling of self-determination is an illusion masking automatic cognitive processes evolved for survival. We have an inner drive to make sense of our experiences and choices post hoc even if they arise deterministically from genetics and external stimuli. There may be no ghost in the biological machine of our brain.

If anthrobots are designed biological systems, perhaps humans are as well. Our neural networks may enact predetermined functions modulated by nature and nurture. We are intelligent creatures with self-awareness, but not necessarily self-determination. The Buddhist belief that the “self” is an illusion resonates with this view. From this perspective, free will could be a narrative construct to maintain psychological control rather than an empirical reality.

However, the universe may not be wholly deterministic either. Quantum physics reveals an inherent randomness at subatomic scales that contradicts rigid Newtonian causality. If our brains have quantum aspects, some spontaneity could emerge like genetic mutations. But whether true free will exists remains scientifically unproven and philosophically debatable.

Anthrobots represent a milestone in humanity’s ability to engineer living systems that blur the machine-organism divide. As biotechnology advances, we may find opportunity but also profound challenges in altering cellular and cognitive functions. Just as anthrobots display capabilities distinct from their original tracheal purposes, we may gain powers to transform ourselves in radical ways.

And if we are biological automatons, who or what is programming us? As we shape the small-scale worlds of cells, are we simultaneously being shaped by forces larger than ourselves? The creation of anthrobots forces us to look inward at our own hybrid mechanical-spiritual natures. The answers may reshape society and life as we know it. Whatever the case, our quest for knowledge marches on, sometimes outstripping our ethics and wisdom. But such is the double-edged sword of realising our scientific potential for better or worse.