From the BBC News website this morning:
"Intelligent children are more likely to become vegetarians later in life, a study says. A Southampton University team found those who were vegetarian by 30 had recorded five IQ points more on average at the age of 10... Twenty years after the IQ tests were carried out in 1970, 366 of the participants said they were vegetarian - although more than 100 reported eating either fish or chicken." [my emphasis]
Perhaps they should deduct 10 points from people who think fish and chicken are vegetables.