Bioelectricity, Morphogenesis, and Two-Headed Worms | Michael Levin

There's a really deep and interesting thing about plenarian, but let's talk about head and tail decisions. In most textbooks, what you'll see is they show the worm being cut into thirds. So there's like two cuts and then they draw this like gradient and they say, "Well, this is how you know where the head and

tail is." That's all well and good, but what they're neglecting to show you is the simpler but much more challenging version of one cut. Because if you make one cut in the middle, the cells on the left side of the cut are going to make a tail. Cells on the right side of that

cut are going to make a head. Their positional information is exactly the same. they were neighbors until you came with your scalpel and cut them apart. And just purely logically, you can't tell locally whether you should be a head or a tail. You have to communicate with the rest of the tissue. I wanted to

have one giant eyeball. I wanted the whole thing to be one giant eyeball. So, what I would do is I would go in and inject like an eight cell embryo. I would inject every single cell like, "Okay, this thing's going to be a giant eye." No, you can get multiple eyes, but you will never get a bigger eye. There's

something that we haven't cracked yet where they know what the size is. The first two-headed worms were seen around 1903, made by a completely different process. Nobody had thought to recut them for over a hundred years. Why? Because everyone thought it was obvious what would happen. This week, Michael and Shingu spoke with Dr. Michael Levan

about how bioelectric signals guide development, regeneration, and collective cellular decision-making. Levven explains how voltage patterns help tissues determine body structure, why cells communicate like networks, and how manipulating bioelectricity can induce regeneration, alter anatomy, and even create two-headed plenarian worms. We also discuss morphagenesis, memory, and living systems, and the possibility that biology operates through high level