This is story from the lab where my mom used to work. The people she worked with were doctors, as in new graduates from medical school. They often had a very limited view of the world and ignored everything else. They got on the subject of chickens and eggs one day and one of these young doctors asked my mom, seriously, how does the rooster fertilize the egg, does he have a tiny drill or something to get through the hard shell? He must have passed biology at some point, right? And yet my mom had to explain bird reproduction to him.