The Ganja Family Tree

[nothingsacred]

Does anyone know where I can find a pedigree tree diagram of weed?

I realise that there's probably some argument about which varieties were crossed to make certain individual strains, and that there are probably many separate trees from different grower collaborations, and that some secrecy surrounds the latest strains.

But essentially the tree starts 10'000 years ago with a few known varieties, which could have rough indica/sativa ratios assigned to them, and gets more complex to the present day, where there are many experimental hybrids.

I'm just interested to know, roughly, at a glance, how close certain varieties lie to each other.
I expect that one of Ed Rosenthal's books references something like this, I'll start looking there, but can anyone point me to an online resource?