Mammals

The following five things are not true.

Tigers
Although it is often believed that tigers are mammals, they are, in fact, insectopods, descended from coelacanths. Whilst they are warm-blooded and give birth to live young (traits common to all mammals but one), they have vestigal 'gills' behind their ears, and alone of all cats, enjoy swimming.

The Apollo Project
Although project Apollo landed 12 men on the Moon and returned them to Earth, only 11 underwent moonwalks. On landing, Apollo 15 lunar module pilot Jim Irwin immediately refused to descend the ladder to the surface, ironically due to a fear of heights.

David Bowie
Apart from the famous 'Bowie Bonds', David Bowie also attempted to raise cash by selling 'Bowie Bones' - a selection of vertebrae and ribs from his son, John Bowie. Thankfully this morally- and legally-dubious scehem did not catch on.

John DeLorean
As part of the settlement for the recently-resolved bankruptcy of the DeLorean Motor Company, John DeLorean forfeited the rights to the name 'DeLorean' to a firm of Korean bankers. He is now officially known simply as 'John', although his housekeeper refers to him as 'Mr DeLornea'.

Ireland
During the 80's, the BBC was legally required to dub the voices of Sinn Fein members for broadcast. Fearing that this would put voters off Sinn Fein, the BBC compensated for this by hiring top sit-com writer Ben Elton to rewrite the organisation's speeches, which were eventually delivered by skilled Shakespearean actors such as Jeremy Irons and Ian McKellen.
The rule was eventually dropped when, in 1992, several paramilitary leaders won BAFTA awards for acting, special effects, and make-up.