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The author claims 20 generations would be enough to breed the powers shown and thousands is unrealistic: " even the most pessimistic estimates of how many g

The author claims 20 generations would be enough to breed the powers shown and thousands is unrealistic: " even the most pessimistic estimates of how many generations it might take to drastically increase average human intelligence or almost entirely eliminate a nasty recessive by R.A. Fisher might be 20 generations . " But some of the powers, like remembering ancestors memories barely even exist in humans today. The field of epigenetics has proven that a starving parent can alter how the genetics of even grandchildren express themselves. So some basic functions like wrapping DNA tighter or loser and adding a methyl chemical group exist to pass information across generations, but this is like an extra bit or two per gene. To extend the functionality to the level of recording memories would take almost as long as it took for DNA to become as fancy as it did from the original RNA molecules that could produce more of themselves without any enzymes or DNA having developed yet. So almost as long again as life itself has taken, not 20 years.

gwern 8y ago
> But some of the powers, like remembering ancestors memories barely even exist in humans today. That would be a valid point... except why are they still breeding for things like intelligence? That was my point. Thousands of generations later, they're still breeding for basic stuff like enhanced intelligence, which makes little sense under pretty much everything we know about intelligence's genetics. > The field of epigenetics has proven that a starving parent can alter how the genetics of even grandchildren express themselves. The extent to which transgenerational heritable epigenetics matters in humans has been wildly exaggerated by the media and the field is rife with overinterpretations, small samples, and non-replication. Not to mention, even that hype didn't exist when Herbert was writing it, so he couldn't've been thinking of it. I am fairly sure he was gesturing towards a more Akashi-Records-style psi mechanism with access granted by ancestry, not actual encoding of memories into spare DNA (which among other things would mean no ancestor would remember anything after having a kid). > To extend the functionality to the level of recording memories would take almost as long as it took for DNA to become as fancy as it did from the original RNA molecules that could produce more of themselves without any enzymes or DNA having developed yet. Neurons already re-edit and splice their chromosomal DNA, so the mechanisms are already there for at least part of it.

gwern 8y ago

> But some of the powers, like remembering ancestors memories barely even exist in humans today. That would be a valid point... except why are they still breeding for things like intelligence? That was my point. Thousands of generations later, they're still breeding for basic stuff like enhanced intelligence, which makes little sense under pretty much everything we know about intelligence's genetics. > The field of epigenetics has proven that a starving parent can alter how the genetics of even grandchildren express themselves. The extent to which transgenerational heritable epigenetics matters in humans has been wildly exaggerated by the media and the field is rife with overinterpretations, small samples, and non-replication. Not to mention, even that hype didn't exist when Herbert was writing it, so he couldn't've been thinking of it. I am fairly sure he was gesturing towards a more Akashi-Records-style psi mechanism with access granted by ancestry, not actual encoding of memories into spare DNA (which among other things would mean no ancestor would remember anything after having a kid). > To extend the functionality to the level of recording memories would take almost as long as it took for DNA to become as fancy as it did from the original RNA molecules that could produce more of themselves without any enzymes or DNA having developed yet. Neurons already re-edit and splice their chromosomal DNA, so the mechanisms are already there for at least part of it.