I am not even half way through this video (53:30) and I thought of an answer that seems to be perplexing scientists about human migrations. I have not heard anyone else propose this theory, but I bet someone else already has. Here it is just in case I am the first:
I don't know much about migratory birds, but it seems to me that our human ancestors were much more in tune with their surroundings including bird migrations. If a they knew which birds were land dwelling as compared to aquatic birds, wouldn't they notice where they were migrating to? If these humans were living at the edge of a sea or ocean and they noticed land dwelling birds migrating away from the land and away into the sea or ocean, wouldn't that lead those humans to assume the birds are headed to some land on the other side of the sea or ocean? As BionicDance says: Just sayin'.
Another crazy utterance from the crazy man.