Harkness test refers to a humorous set of instructions regarding sexual interaction with a fictional creature that is not a human.
The name of the guideline refers to Captain Jack Harkness from the television series Dr. Who and Torchwood, who is known for his indiscriminatory nature when it comes to sex.
Over time, the “Harkness test” which was in the form of an infographic, started to be used as an exploitable format for memes about having sexual intercourse with various fictive beings, including monsters from Scooby Doo as well as various Pokémon beasts.
Captain Jack Harkness (portrayed by John Barrowman) is a character from the 9th and 10th arcs of the Dr. Who series, who is known for being “omnisexual” which means he has a romantic interest in even non-human species.
His name and behavior served as the inspiration for the name of the test as well as the meme derived from it.
The test basically consists of finding out if an alien specimen is sapient and adult, to avoid bestiality and paedophilia.
The first time the “Harkness test” infographic emerged online can be dated to January 6th, 2013, when user BeakieHelmet posted it to Furaffinity.
It soon appeared on Imgur, posted by MeloDoggo3928 on February 8th, 2013.
Starting in February 2013, the popularity of the “Harkness test” grew steadily over the years, spreading to sites like Reddit and Derpibooru, a My Little Pony fan site.
It also grew popular on Tumblr, appearing in several posts, all containing an edit of the original infographic, applying its rules for creatures from ficitonal universes.
The definition of “Harkness test” was uploaded to Urban Dictionary on July 20th, 2019 by user imsorrymom, after the popularity of the phrase was boosted by a mention in a Plague of Gripes video.