parrot - While understanding of the relationships between subgroups of true parrots - e.g. the one containing the Grey Parrot vs. the relatives of the budgerigar - are rather well resolved and knowledge of relationships between species has much improved in the last years, it is still a matter of dispute whether the distinct lineages of true parrots should be considered subfamilies or tribes. Due to parrot fossils and molecular divergence date estimates providing insufficient data to properly resolve when exactly the major diversification and divergence periods in parrot evolution took place, i.e., how distinct the various lineages are really from each other, or how fast and radically they were changed by evolution.