The DNA samples used to identify a "true" wildcat include a Victorian specimen kept in the British Museum - providing a sample with 63, 000 genetic markers.

BBC: When is a wildcat really a wildcat?

Even though the sample card was half of the size of an actual Social Security card, was written in red, and had Specimen written in bold (see above), many people mistakenly thought it was their own Social Security number.

FORBES: Tax Trivia Giveaway #4: Social Security Numbers