Medicine has been fascinated with leeches for centuries, using them to thin the blood, remove clots and deal with hypertension. Now Potro Dhorma is bringing leeches into the world of Quantum Physics by seeing the world through the eyes of a leech.
“Leeches are incredible creatures. For something so seemingly fluid and unstructured, they’ve been designed very carefully. They are simple in structure, very simple, and it’s this simplicity that gives rise to perfect structures within the animal. The distance between the eyes is exact, correct to within nanometres in some species. This allows for precise measurements time taken between pulses of light reaching the sensors and subsequently the brain,” says Dhorma, “There are fifty receptors per eye, with a rigid, perfect alignment of each receptor, no lens to get in the way, so minimal processing power is required to interpret a signal.”
Building robots to accurately measure light pulsations is expensive and more complicated that one might think, he says, and operating on such a small scale means that often tolerances are exceeded.
“The experiments we are performing require very, very precise measurements. These can only come from very finely crafted sensors. It turns out those sensors are already being grown on our little friend here,” he says, holding up a leech for observation, “And we are not blessed with only one pair, but five.”
Asked whether there was a particular species of leech in use, Dhorma was quick to say that he could not identify it, given the secretive nature of his research. He did say, however, that he and his team are growing leeches in vats to genetically engineer a strain of perfect specimens.
“These critters will not be released into the wild. They are laboratory leeches only. Once we have perfected the strain, which, by our estimations based on convergence, should be within another fifteen generations, then we will be looking to patenting the creatures and selling them to the scientific community.”
When asked about how to use the leech, Dhorma demonstrated by dissecting one in front of us, attaching electrodes to the optic nerves, and hooking it up to a computer. He then showed how he can measure the time taken for photon interaction between the two sensors, and how they measure up against standard laboratory equipment.
“See, this sensor array here costs around two hundred dollars, it’s cumbersome to calibrate and it’s fragile. This leech would cost – including growing, harvesting, distributing and connecting – about five dollars when you add it all up. The results, even at this early stage, are almost identical,” he says proudly.
He says the working time of the eyes is around twenty four to forty eight hours after ‘harvest’, after which the results decline rapidly. The rate of decline is predictable and scientists could work around the shortfall.
“Of course, we could look at a solution whereby the leech is kept alive but immobile, perhaps with a kind of paralysis toxin. This would be ideal and an even more cost effective option.”