written by Thom Garrett
edited by Danna Colman
“There is no need for alarm,” said the lead researcher at the University of Vermont, something that no one ever says if it’s true.
They are called xenobots — tiny, living, programmable robots made entirely of stem cells scraped from frog embryos. Skin cells bonded to provide structure and pulsing heart cells synchronized, resulting in motion. Tiny pink blobs swam like tadpoles in a saline solution and even hopped around on the sterile agar of petri dishes. Quite unexpectedly, the little beasties gave their creators a couple of surprises. First, they began to display the unexpected capacity to heal if cut. Second, when “programmed” to push tiny pellets, small groups of xenobots spontaneously coordinated their actions, swimming in a circle and working together to push the pellets to the center, effectively corralling them.
The scientists were understandably exuberant as they toggled together new versions of the tiny xenobots through the use of a microscope and a couple of tiny tools. They took their original designs from dozens of body plans generated by a supercomputer and then tested their efficacy with specific tasks, discarding the less able and focusing their efforts on improving the performance of the more able. It was very much like evolution through natural selection, although this selection was biased and decidedly unnatural. They even modified one of the designs that moved better than the others by giving it a hole in its middle, like a tiny, living donut. The hypothesis was that this would reduce drag and improve the efficiency of its movement. It was only later observed that the little guy with the hole in its middle could hold something there and carry it along while it moved so efficiently from here to there. Who knew?
Now, on a completely different and unrelated topic, did you know that in the early stages of development embryos are just a blob of undifferentiated cells? The first really big-deal change is when that blob develops a hole in the middle. That’s interesting, isn’t it?
But I digress. When the xenobots were finally unveiled, the response on social media was huge! The scientists were overnight rock stars, and one might be tempted to say that the xenobots went viral, but that would be an ill-advised choice of words. Whatever words you choose, the result was that the scientists were suddenly extremely busy and the lab was a chaotic, media-driven circus. It’s perfectly understandable that, under those circumstances, a young child might not receive the kind of supervision he should have had. But there’s no need for alarm.
Little Josh, Jr., the lead researcher’s son, toddled around the lab, peeking around tables and dodging the long legs of too many adults moving too fast in the crowded space. He dragged a stool to his special spot and climbed up. He peered into the tank, looking for his favorite. It didn’t take long because it was even bigger than yesterday. Josh called him Donny the Donut, and he had taken a special interest in the little guy ever since he’d noticed him chasing the other bots around the tank. He’d tried to get any of the adults to see it, but they were all too busy, so Josh just sat and enjoyed the show.
Donny was faster than the rest so he could easily catch up to one, but the tricky part was getting it into his donut hole. He eventually got one, and then another. As he absorbed their cells and released their stored energy, he was able to re-organize his bits and pieces. He grew larger and faster, and he shaped his donut hole to be better at catching and holding the littler bots. Today he was as big as a lady bug, and he had eaten almost all of the others.
Josh excitedly hopped down from his stool and ran to his bedroom. He grabbed the little net from his saltwater aquarium and trotted back to the lab. Donny was easier to catch than a fish, and a moment later Josh was tipping him into the water.
He stood there, his nose pressed to the glass, and he watched as Donny began to move around, bumping into things he had never experienced in his old tank. A rock, a plant, gravel on the bottom. But then that darn angelfish came out of hiding. Josh hated that fish! He had watched it chase and pick at one pretty, new fish after another, chasing them around the tank and tearing their fins apart until they couldn’t escape. And then it would eat them alive. Now it was after Donny.
Donny never had a chance. He was fast compared to the other bots, but no match for a fish. The angelfish poked at him curiously once or twice, and then sucked him in whole. Donny was gone.
Josh was so mad at that angelfish he decided to flush it. He stood on a chair so he could reach down into the water with the net. His anger soon turned to frustration as he realized that the fish was just too fast for him, and he slumped down into the chair and glowered at it as it swam from one end of the tank to the other. After a moment, though, its swimming became erratic. It struggled to stay vertical and sometimes flopped on its side on the gravel. Josh jumped back up and tried again, this time easily netting the flapping fish.
He dropped it into the toilet bowl but didn’t immediately press the lever. He was a born scientist, and he knew he was seeing something out of the ordinary. He decided to watch. The fish ceased to flip or flop at all and just lay there on the porcelain bottom of the toilet. Its mouth gaped and its body trembled, and then it was still. Josh watched as its belly pulsed and then tore open. Eating from the inside out, Donny emerged, as big as a quarter now. He methodically devoured the angelfish, using his donut hole that now was able to clamp down and tear off bits of skin and flesh.
When the last of the fish was gone, Donny lay quietly on the bottom of the toilet bowl, still at first, but then ripples began to roll from one end of his body to the other. As Josh watched, Donny’s little round blob of a body began to grow scales, and then to stretch out, ripple after ripple, taking a long, slender shape like a torpedo. At one end was an opening, the remnant of his donut hole. At the other end, his scaly skin fanned out into a delicate tail. Fins budded and grew on the sides of his body, growing larger with each ripple. And then Donny, as big as Josh’s little hand now, began to dart around in the water, as fast as any fish.
Josh was so excited by how his little friend had grown that he wanted to show his father right away. He reached into the water with both hands and quickly snagged Donny, but Donny wasn’t having any of it. He latched his opening onto a fleshy part of Josh’s palm. As hard, sharp edges cut painfully into his skin, Josh opened his hands. Donny hung there, shaking violently until he tore a hunk from Josh’s hand and fell back into the toilet. Josh screeched with the pain, but then at the sight of his blood dripping from his wound and into the water below, he fell silent.
Josh had been cut before, so he knew what to do. He rushed to the sink and ran hot water over his hand. He washed it with soap and then blotted it dry with toilet paper. Blood still seeped out, but not too badly. He clumsily applied a Band-Aid. In the meantime, Donny swallowed Josh’s skin and absorbed his blood from the water. He lay still and then began to ripple. He didn’t grow much larger, but he re-organized according to a new plan.
Josh’s hand really hurt, and he was as mad at Donny now as he had been at the angelfish. He looked down into the toilet, wanting nothing to do with Donny anymore. Too angry to care, Josh couldn’t help but notice the changes as they occurred. That little body was covered in a patchwork now, changing with each moment from scales to smooth, pink skin. The fins had stretched out, and as he watched, the ripples rolled down each one, and tiny bumps at the end grew into fingers and toes. The front end of the body with the nasty, biting mouth was now topped with a sparse patch of thin brown hairs.
Josh didn’t care. Donny had bit him and it hurt! He didn’t care that he had changed again, or that the scientists might want to know about it. He didn’t want to show him to his father anymore. He didn’t ever want to see Donny the Donut again.
Josh put his hand on the lever and looked down one last time. Lazy eyelids slowly lifted and two brown eyes looked up. Josh flushed. Donny vanished. He was gone. Nothing to worry about now. No need for alarm.