Hair

Hair is bio-material produced mostly by mammals through the skin follicle. It often serves the function of comfort and protection for various types of mammals.

In Smurfs Media
In traditional Smurfs media, male Smurfs are often born relatively hairless, with a beard and moustache grown around 400 years of age, and additional hair grown around the head in advanced stages of physical maturity. Female Smurfs, who are most likely created by magic rather than born, are the only Smurfs commonly seen with a full head of hair. Body hair doesn't appear on Smurfs unless they have been magically altered in their appearance.

The Smurfs (Film)
Gutsy Smurf in the 2011 Smurfs movie is the only known case of a young Smurf his age growing facial hair.

Empath: The Luckiest Smurf stories
In the EMPATH: The Luckiest Smurf story series, one male Smurf called Lord Vladimir Smurfula is shown to have full head hair while most other male Smurfs are generally bald. Papa Smurf grew body hair as a result of his transformation into a muscular, love-crazed grotesquerie from his exposure to an altered form of "pheromone cologne" in the story "Papa's Big Crush." However, after Papa Smurf was purged of his physical desire for Smurfette, the body hair disappeared altogether when his normal appearance was restored.

Smurf hair is often used by Papa Smurf in the creation of Smurf essence, though he primarily uses clippings from his own beard in order to keep the Smurf essence that he makes pure. Empath's eyebrows were used in the creation of Smurf essence in order to save Polaris' life from a degenerative disease that is inherent in all Psyches that are disconnected from the Psychelian mindlink.

Probably because that male Smurfs are bald, their heads tend to be very sensitive to the female touch as it triggers a physical form of stimulation, which is part of the reason that male Smurfs wear hats. It is only during the honeymoon of a newlywed Smurf couple that a female Smurf is allowed to touch a male Smurf's bald head, which leads to the romantic hat-removing mating ritual.

Glovey Story
The main character of the Glovey Smurf story series has head hair due to the fact that he was previously in human form before he was changed into a Smurf. His son Angelo, born to Glovey's wife Smurfette, has long blond head hair. Aksel Smurf has a crown of brown hair that is cut in the style of a friar. Gargamel when he was changed into a Smurf form kept his hair along with most of his human physical appearance.

RDK Stories/Expanded AU
Within The Reluctant Dark Knight series, which crosses over with the Expanded AU, hair exists on nearly ever creature, but below focuses on specific species that are directly introduced.

Humans
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Smurfs
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Other Creatures
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