The trees seen at FTDNA, other companies, and ISOGG are just logical phylotrees based on snps. They indicate the logical time ordering (greater than, less than, connectivities, etc.) of the shown nodes of the tree along with the necessity of shown nodes based on seeing haplotypes with various combinations of snps in derived or ancestral state. These kind of trees indicate no metric or measure of time back to the various nodes. My trees linked to below include all the node time ordering logic obtained from snp information available to me, but they use extended STR haplotype information from large collections of haplotypes as well --- for purposes of putting measured time into the trees. From the STR haplotypes measures of “distance” between haplotypes and their clade MRCAs are obtainable. These “distance” measures are typically some kind of variance or GD like calculable quantity. With measured mutation rates for the STRs present in the haplotypes, these measures of distances between haplotypes can be converted into actual time intervals between the nodes, thereby giving the trees not only logical structure but estimated depth back in time to key node events. Others messaging on this or that forum have been constructing trees with a measured time sense using analagous methods. If the nodes are not too dense, the STR-based methods of measuring time between nodes can also infer the logical ordering of the nodes when the snp information is not yet in hand. That was in fact the rule in haplogroup I in the early days before the recent “explosion” in available snps. Kenneth Nordtvedt See: "Tree for I1" "Tree and Map for haplogroup I" "The I1modalities" at http://knordtvedt.home.bresnan.net showing my working tree for YDNA haplogroup I. These files are periodically updated as new information is obtained.

I agree that the Y-DNA SNP haplotrees at FTDNA, ISOGG, and elsewhere are logical cladograms, though I don't know that I would say — or that FTDNA or ISOGG would say — they are "just" logical phylotrees, not considering the resources invested in building them. A time-axis is implied in all evolutionary cladograms, and it isn't necessary to scale the time axis — by scaling the lengths of the branches — unless the time scale is of interest to the researcher. Sometimes it's the sequence (the correct order of branching) that is a researcher's main interest. Both scaled and non-scaled haplotrees are valuable tools. Diana > From: Kenneth Nordtvedt > Sent: Saturday, March 24, 2012 2:55 PM > > The trees seen at FTDNA, other companies, and ISOGG are just logical > phylotrees based on snps. They indicate the logical time ordering > (greater than, less than, connectivities, etc.) of the shown nodes > of the tree along with the necessity of shown nodes based on seeing > haplotypes with various combinations of snps in derived or ancestral > state. These kind of trees indicate no metric or measure of time > back to the various nodes. <snip>