They do not necessarily accurately represent the species evolutionary history.The data on which they are based is noisy; the analysis can be confounded by horizontal gene transfer, hybridisation between species that were not nearest neighbors on the tree before hybridisation takes place, convergent evolution, and conserved sequences.
But do you understand how that doesn't disprove it? And there's also the mountains of evidence outside of mitochondrial DNA for the age of humans being a lot longer than 6000 years. Seriously, look into it. It's fascinating stuff. Nat Geo did a documentary on it and they have a website about it too.
But anyways, I'm off to bed. Have fun ignoring stuff! You never did get back to me on that other thread, that list of signs of a dangerous group. Maybe I'll bump it tomorrow.