"if Ruddy is capable of wiping out WH, which it seems it is, then isn't the rationale behind them being seperate species being called into question a bit"
An excellent point Brendan, I'm surprised it hasn't been raised before. I assume that studies have been carried out that show that the two have diverged sufficiently to be regarded as separate species (assuming, that is, that they have the same common ancestor) but I don't know this. However, even if they were genetically close enough to be regarded as the same species (see below though) they are still distinct and clearly diagnosible *taxa* and W-h D would deserve conserving regardless of its species or subspecies status. It's hard to get out of the mindset that species are more important than subspecies but as the distinction between the two is often so vague anyway we must make that leap sometimes. The term Evolutionary Significant Unit (and ugly phrase I know but at least it carries the meaning of the concept it refers to well) has sometimes been used in preference to 'species' or 'subspecies', it can be usefully applied in this case.
In any case, there isn't, as far as I'm aware, an agreed point of genetic divergence at which a subspecies becomes a species anyway. Genetics, thankfully, is not the only taxonomic measure used (and it isn't the holy grail some imagine it to be), though it is nevertheless a very useful and interesting tool.
I'm not a geneticist and I don't pretend to understand genetics very well, so if anyone can correct any of the above or offer further clarification I'd appreciate it!
Dave
