Hi Guys

I was wondering why ljk hadn't posted that one yet.

The impression I got is that he's advocating the view that ETIs actually travel via transmitting information sufficient to reconstruct themselves at their destination and he was pointing out that the apparent information required to transmit a body is less than commonly imagined.

My criticism of that is that there's no such thing as 100% faithful reconstruction of any complex lifeform based on the same DNA sequence because epigenetic factors play a big role in development and growing a body naturally is too damned slow as any kind of "teleportation". A body reconstruction would require a lot more information - to specify a single living cell requires a massive amount of information. Contrary to our usual impression DNA doesn't exactly tell cells how to do that - all the parts are encoded but the chain of life back to the Last Universal Common Ancestor means that there have always been decoding bio-machines in the cell ready to decode and reconstruct the genetic code. No cell appears without a "mother". A transmission of viable life would need to specify both in sufficient detail. Many of the components self-assemble but the overall organism lives in a particular context with particular stimulii providing reference points.

However if the destination already has a vat of cells ready and willing to be told how to get together then the required information will be a lot less. I'm sure a lot of repetition is involved in body making as the coding part of our DNA is only about ~ 15 megabytes and the regulatory regions around it about double that. Yet we each have about 256 different types of cells and about 75 trillion all told. The output file is much bigger than the source code.

Adam