Viviane you asked why draw the line where I did. It was a suggestion. The line was drawed becaused it fit the data and a pattern was found. Why use the definition of species when is flawed? You have horses and donkeys mating and some of the offsprings are not always sterile. If you take the definition of species that they can only mate with their own species and produce only that species then mathematically you could prove that a species could NEVER produce another species therefore prooving evolution doesn't exits. Since we know that is not the case the definition of species if flawed. Start with a wrong premise no wonder is impossible to find the first human(s).
cofty you say " It's not really a "current limitation", it's intrinsic to the task of trying to put the continuum of life into neat boxes."
That was my point why put a continuum in neat boxes why not redefine them and make the models fit better? Sure it might be more complex but it could help explain things better. But maybe someday you'll become less close minded and find out there are more ways than one to look at something and more than one solution to most problems, and if we all limited ourselves to what the science says now and what other scientists have written down there would never be any more breakthroughs. My suggestion was why not do it differently, your answer: because it will not work. OK I understand you now all the infinite number of models have been tested and they don't work, I am glad we clear that up it might save someone a lot of time when they think about trying something different.
Viviane usually programs are squishy(have bugs) because we don't have the same standards as other disiplines and we get away with it. Compare a bridge collapsing vs a program crashing. Some fields required very robous and bug free coding but those are few.
Thanks Apognophos I was beginning to think no matter how I try to explain myself I failed.