"These results support the notion that, also inside the family of N1 subtypes, a clear distinction can be made to distinguish avian-like H1N1, such as the one from the current outbreak, from other existing H1N1 strains." What would be the explanation for this? A recent recombination between an avian-like H1N1 or has it diverged from other avian like H1N1 with the recombination occurring much earlier. Could this information be superimposed in phylogenetic context on current figure 3 ?