I was having a snack with DS4 at Starbucks and drew his attention to a "Coffee Belt" world map. I mentioned that the shaded areas were where coffee beans grow. His eyes flickered to the map and he almost instantaneously said "Oh, they grow in Mqdagascar, I wonder if lemurs eat them."
No one heard that, but we did get some funny looks later when we walked by the map again and he said "I notice that coffee grows in Australia, but only in a very small area."