Science nerd post redux (or: I have no idea why I sat down and wrote this)
Scientists invent a gel that undergoes peristalsis
This may be far more interesting to me as a result of being in a medical field, but plainly stated: this is really fucking cool.
A quick primer: peristalsis is the system of movement that your bowels perform in the process of digesting food. It's basically your intestines rhythmically contracting and relaxing in order to slowly move the digested food (at this point referred to as chyme) further along the digestive tract. Imagine holding a very long tube of cookie dough, placing your hands at one end of it and squeezing, and then squeezing in intervals further down the tube to propel the cookie dough out. It's essentially the same mechanical process.
But peristalsis is a negative feedback mechanism, meaning that at some point, peristalsis will result in a product that will then stop the peristalsis itself. In this case, the peristalsis will eventually move the chyme through the intestines and to the colorectal area, where the absence of distension in the tract will tell the brain that there is nothing present in the small intestines, and so peristalsis stops.
Not only is it incredible that scientists have a created a gel that can perform peristalsis, but I think it's even more incredible that it functions as a positive feedback loop. Unlike negative feedback, which eventually results in the original process stopping, positive feedback produces a product that continues, or intensifies, the first process. A textbook anatomy example of this is contractions in childbirth. Contractions of the uterus signal a release in the hormone oxytocin, which itself has the effect of further intensifying the uterine contractions. So, as per a positive feedback loop, the original contractions are intensified. Just to drive the point home, if this were a negative feedback loop, then the contraction would release an inhibitory hormone that would stop the contractions, rather than intensify them.
The real insight here, at least for me, is what this offers in terms of understanding evolution. This gel highlights that mechanical byproducts such as peristalsis, which are necessary to our life, are basically certain configurations of the right chemicals. Keeping this in mind, it's a little easier to imagine at some point in evolutionary history, some organism developed this ability and it proved tremendously useful, so selection pressures saw fit to keep it. Another way to think of it is that scientists just reconciled one of the many puzzle pieces to explain how it is that we arose as the organisms we are. As we continue to reconcile the puzzle pieces and "put them together," so to speak, we get much closer to understanding the creation of life.
We already have filters--called diasylates--that efficiently act as an external kidney and filter our blood. We already have pacemakers that can spur the action of a heart beat, and mechanical pumps that we can pair them to. We're getting closer to full-fledged artificial intelligence all the time, and our progressing insight into the workings of the brain is astounding. We've become quite adept at simulating the mechanics of walking. Now we can add to this collection a gel that can stimulate the actions of the digestive tract. It's not altogether implausible to imagine putting all of these inventions together in the far future to simulate the many functions that equate to the human body. At that point, it won't be so easy to point at such a thing and say "that's not alive," especially if it can do all the things that we do.
This reminds me of a project by the engineer/artist Theo Jansen, where he essentially creates a number of creatures that can respond to stimuli and adapt to problems. Granted, his creatures are extremely rudimentary, but the basic principles that in all likelihood give rise to more the complex characteristics of life are there. For us to say that Theo Jansen isn't creating life, or that the peristaltic gel described above doesn't provide insight to how we came to be, is like my laptop turning to the calculator that sits in my dresser drawer and saying "You're not really a computer."
In conclusion, I need to get out more.
This may be far more interesting to me as a result of being in a medical field, but plainly stated: this is really fucking cool.
A quick primer: peristalsis is the system of movement that your bowels perform in the process of digesting food. It's basically your intestines rhythmically contracting and relaxing in order to slowly move the digested food (at this point referred to as chyme) further along the digestive tract. Imagine holding a very long tube of cookie dough, placing your hands at one end of it and squeezing, and then squeezing in intervals further down the tube to propel the cookie dough out. It's essentially the same mechanical process.
But peristalsis is a negative feedback mechanism, meaning that at some point, peristalsis will result in a product that will then stop the peristalsis itself. In this case, the peristalsis will eventually move the chyme through the intestines and to the colorectal area, where the absence of distension in the tract will tell the brain that there is nothing present in the small intestines, and so peristalsis stops.
Not only is it incredible that scientists have a created a gel that can perform peristalsis, but I think it's even more incredible that it functions as a positive feedback loop. Unlike negative feedback, which eventually results in the original process stopping, positive feedback produces a product that continues, or intensifies, the first process. A textbook anatomy example of this is contractions in childbirth. Contractions of the uterus signal a release in the hormone oxytocin, which itself has the effect of further intensifying the uterine contractions. So, as per a positive feedback loop, the original contractions are intensified. Just to drive the point home, if this were a negative feedback loop, then the contraction would release an inhibitory hormone that would stop the contractions, rather than intensify them.
The real insight here, at least for me, is what this offers in terms of understanding evolution. This gel highlights that mechanical byproducts such as peristalsis, which are necessary to our life, are basically certain configurations of the right chemicals. Keeping this in mind, it's a little easier to imagine at some point in evolutionary history, some organism developed this ability and it proved tremendously useful, so selection pressures saw fit to keep it. Another way to think of it is that scientists just reconciled one of the many puzzle pieces to explain how it is that we arose as the organisms we are. As we continue to reconcile the puzzle pieces and "put them together," so to speak, we get much closer to understanding the creation of life.
We already have filters--called diasylates--that efficiently act as an external kidney and filter our blood. We already have pacemakers that can spur the action of a heart beat, and mechanical pumps that we can pair them to. We're getting closer to full-fledged artificial intelligence all the time, and our progressing insight into the workings of the brain is astounding. We've become quite adept at simulating the mechanics of walking. Now we can add to this collection a gel that can stimulate the actions of the digestive tract. It's not altogether implausible to imagine putting all of these inventions together in the far future to simulate the many functions that equate to the human body. At that point, it won't be so easy to point at such a thing and say "that's not alive," especially if it can do all the things that we do.
This reminds me of a project by the engineer/artist Theo Jansen, where he essentially creates a number of creatures that can respond to stimuli and adapt to problems. Granted, his creatures are extremely rudimentary, but the basic principles that in all likelihood give rise to more the complex characteristics of life are there. For us to say that Theo Jansen isn't creating life, or that the peristaltic gel described above doesn't provide insight to how we came to be, is like my laptop turning to the calculator that sits in my dresser drawer and saying "You're not really a computer."
In conclusion, I need to get out more.