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Comment by swamp40 | Hacker News Reader

All cell networks can contain memories, not just neurons.

Plant and animal body shapes (morphology) are determined from memories stored as voltage gradients) inside cells, not from the DNA. Just like neurons are good at allowing the body to navigate in 3D space (our world), other cell networks are good at creating 3D shapes (leaves, fingers, legs, livers, etc.)

You can decouple them, provide your own voltage gradients and get new body shapes using the same DNA.

https://www.xenobot.group/ https://www.drmichaellevin.org/ https://twitter.com/Kriegmerica

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This is a wild misstatement of what is going on. Morphogenesis is primarily governed by chemical interactions between proteins, on cell surfaces and secreted into intercellular space, as has been studied for decades:

https://en.wikipedia.org/wiki/Developmental_biology

And the proteins, and the maps and schedules for their production, and the machinery which gives them effect, are all encoded in the DNA.

I haven't actually followed Levin's recent work, so i don't know if he's going round actively misleading people about this, or if people are hearing about his work and assuming that's the whole story. To be honest, from what i've heard, he seems like a crank.

I don’t think Levin is a crank. He went on Lex Fridman’s podcast and talked about his bioelectricity work and morphogenesis. Like you said, I think people who don’t know much about development took that to be the whole story, when in reality it’s just one academic doing what academics do best: talk about their own work.

Edit: one small quibble with your comment is that it’s too reductive to say that morphogenesis is all encoded in the DNA. It’s really an emergent property of the whole system. Like DNA is only a few billion base pairs, which is not nearly enough to store the precise positions of every cell, much less every protein.

Thanks, this makes sense.

I think my reduction and your quibble is really a matter of semantics. It's true that the genome doesn't contain explicit coordinates for every feature of every cell. But at the same time, if you start with the same DNA, you get the same morphogenesis, and if you start with different DNA, you get different morphogenesis, so i would say the morphogenesis is very much encoded in the DNA. It's just that it's in a highly compressed representation, and the decompression machinery includes the laws of physics!

> if you start with the same DNA, you get the same morphogenesis

Then how do you explain their creation of xenobots using only frog DNA?

That was the whole point of the experiment - to disprove your statement.

https://wyss.harvard.edu/news/team-builds-first-living-robot...

Okay, same DNA in the same context then. That experiment doesn't disprove it in the slightest. Indeed, the fact that the experiment is repeatable confirms it.

Yeah sounds like we are both expressing the same idea.

I’m usually pretty touchy about software analogies for biology but “decompression machinery includes the laws of physics” is a good way to frame it.

This is related to the electricity guiding embryo formation of a frog, discovered back in 2011? https://now.tufts.edu/2011/07/18/face-frog-time-lapse-video-...

Yes, you can literally see the pattern of the face. And change it. Can you imagine the next 50 years?

I bet that this upcoming century will have advances in this field that will validate some of what the ancient monks had going with their concepts of "Chi" in China and "Prana" in India. Their "Energetic Life Force Residing in each cell"

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