Captains log: Our initial assumption regarding the dominance of marsupial mammals has been proved incorrect. Apparently, they have only flourished on this one continent. Why this should be, we are not quite sure. Either the previous expedition did not see fit to note this, as their main regard were the search for intelligent species, or some sort of major event has taken place on this continent.
We have further tried to contact the whales, and in particualr the doplhins, but something strange seems to have occurred. They are still intelligent creatures, but it seems that they have devolved from their present level of sentience, and are now at the same level as a Arilou child! We are not sure why this has happened, but clearly some sort of major event has taken place while we were absent.
While the devolvement of the whales is an intriguing fact, it is still not vital to this mission. Now that we have collected the background facts, we will commence a deeper study of the earthlings themselves.