On 10 April 2013 I watched an episode of Pointless in which, at the penultimate stage, the two remaining couples were asked to identify British birds that have two-word names. They were shown photographs of five birds, which were labelled as ---- Thrush, ------ Duck, ---- Bunting, ---- Wagtail and -------- Dove.
Both couples chose to name the Wagtail, with one couple identifying it as a Grey Wagtail and the other pair as a Blue Wagtail. Both were wrong, because the Grey Wagtail is an altogether different bird and the Blue Wagtail is a tropical fish. The correct answer was Pied Wagtail.
Except that it wasn’t.
Incidentally, as many as 47 of the 100 randomly selected people described the wagtail as a Pied Wagtail. Only the Song Thrush was more frequently identified, with 50 subjects able to name it. The pigeon was correctly identified as a Collared Dove by 23 of the 100. Perhaps surprisingly, more people were able to name the rare Snow Bunting (12/100) than could identify the much commoner Tufted Duck (7/100).
[And when the episode was repeated on 16 March 2015, there was no acknowledgement of the Pied/White Wagtail error.]