Marsupial evolution

[q] I do think marsupials are a more ancient lineage than placentals [/q]125 million years is supposed to be the age of the oldest placentals and marsupials found to this day, indeed. Without having gone into details of the discoveries, the fact of carrying the baby outside can be seen as sophisticated but also as primary. I can' tmake an opinion for myself on that, but i find it very interesting