Can you imagine the possible image of a future robot? What does it look like? The T-1000 from Terminator 2? Transformers from Cybertron? Or an agile robot with unprecedented mobility like those developed by BostonDynamics? Indeed, most of the human technologies are made from steel, plastics, and chemicals, so are robots. But the story has changed since advances in computational search and 3D printing made manufacturing physical instances possible. In 2020, researchers from the University of Vermont and Tufts University engineered living robots, called Xenobots, using skin and heart cells from frogs. Yes, they are the moving tiny blobs in the picture.
How were they created?
They are the products of computational design and biological manufacturing.
The first step of computational design is the evolutionary algorithm. The evolutionary algorithm creates multiple generations and thousands of candidate solutions for new design forms, and simulates each design in a physics-based virtual environment, and automatically assigns performance scores. The lower-performing design will be deleted and overwritten by a randomly modified copy of the higher-performing design. Repeating this process can yield diversified and high-performance design solutions. Then, performance filters are used to judge and delete the design that does not meet the requirements. There are mainly two filters. The first is “Robustness Filter”, which is mainly used to judge and delete those designs that cannot resist the chaotic and complex physical environment through noise resistance. The second is “Build Filter”, which is mainly to judge and delete designs that are not suitable for the current biological construction method.
Biological manufacturing comprises stem cell culture and micromanipulation. First, scrape the skin cells and the early cells of cardiomyocytes from the Xenopus embryo at the blastocyst stage, separate them into single cells, and then incubate the different cells in a layered stacking manner. Then the researchers used tiny tweezers and electrodes to manually shape the gathered tissue, and manipulate it under a microscope to shape it into the approximate shape designed by the computer.
What can they do?
Don’t be fooled by their appearance, they are genuinely advanced machines. “These robots can move, explore, and collaborate on their own,” said the research team. They can move on their own without additional nutrition, exploring in a watery environment for days to weeks. Even if they are cut open, they can heal automatically. What is amazing is that these simple cellular robots exhibit surprisingly complex behavior characteristics, such as circling together or herding cellular debris into piles. They have a hollow structure, which means they can carry some objects (such as drugs) to designated areas, and these characteristics and functions undoubtedly have high research value and prospects in the fields of medicine, biology, chemistry, etc.
Will this be another Pandora’s Box?
To attract eyeballs, many media have rendered an atmosphere of fear in their reports, and people felt that this biological design will eventually destroy humans, just like in many science fiction movies. I can hardly agree. Please do not underestimate the greatness of the creator of nature. The simplest life in nature can go up to Mount Everest, down to the Mariana Trench, enter the edge of the earth’s atmosphere, and even parasitize in the human body to coexist with us. Their complexity is not in the same order of magnitude.
We do not need to be afraid of this breakthrough in scientific research. We should realize that every major discovery in human history has greatly promoted the development of human civilization, and this time will not be an exception. Perhaps, there indeed are crazy scientists in reality, just like the villain characters in Spiderman movies, who want to use their research findings to do some crazy things. This brings me to the last point I want to make. We need to conduct reasonable supervision of scientific research under the premise of complying with the law and try to build a new ethical framework to deal with possible subversive ethical threats.
Source:
Kriegman, S., Blackiston, D., Levin, M., & Bongard, J. (2020). A scalable pipeline for designing reconfigurable organisms. Proceedings of the National Academy of Sciences of the United States of America, 117(4), 1853–1859. https://doi.org/10.1073/pnas.1910837117
https://www.wired.com/story/xenobot/
https://www.uvm.edu/news/story/team-builds-first-living-robots
