Were there any marsupials in Gondwana?
Monotremes (like echidnas and platypus) are known to have been in Australia and South America while they were still part of Gondwana, but the oldest marsupials we know of are from the early Cainozoic (about 62 million years ago) after the separation, from both Australia and South America. For them to appear on both continents there must have been some common ancestor in Gondwana, but we are still looking for it.
