Skin pigmentation
Skin pigmentation, also known as skin color or skin tone, was the natural coloration of one's skin. It could also be referred to as complexion. ()

The graduations of pigmentation from black to brown, to yellow to white, were genetically predictable and were given an explanation from the earliest writings on genetics by Gregor Johann Mendel to the most recent nucleotide studies. The rare exception was the Cheron natives who were black on one side and white on the other. () Andorians sometimes referred to Humans disparagingly as "pink skins," though Thy'lek Shran, after getting to know Jonathan Archer, came to refer to him affectionately using the term. (, et al.) Individuals whose skin was seen as abnormally pale were called albinos. (; , et al.)

The space-borne organisms living in the Alpha Onias system changed their pigmentation from brown to green when feeling threatened. () 

On Earth, brown-skinned Humans (often referred to as "black") historically faced racism from those who were white in some cultures. In discussing why he did not wish to visit the holosuite program Vic's with his wife, Kasidy Yates-Sisko, Benjamin Sisko noted that in 1962 in Las Vegas, black people weren't very welcome in lounges like Vic's, except as performers or janitors, the Civil Rights Movement still being in its infancy. To this, Kasidy responded that the program would not cause them to forget who they were or where they came from, but it did remind them that they were no longer bound by limitations, except those they placed on themselves. ()

Members of the Andorian species generally had blue skin, though members of the Aenar subspecies were a pale white. The Aenar referred to Andorians as blue skins. () 

When Doctor Phlox studied epithelial cells from a Xindi pilot in 2153, he found the pigmentation far more colorful than he'd expected and later identified them as scales. () 

In the 23rd century, albino Klingons, such as Voq, were seen by some in their culture as being a mistake of nature. ()

Harry Mudd's complexion was "fair", according to his police record. ()

In 2266, an android duplicate of Doctor Roger Korby called Christine Chapel's attention to Andrea's lifelike skin pigmentation and the variation in her skin tones. ()

In 2267, Trelane described Lieutenant Uhura of the  as having the "melting eyes" and skin of the same "lovely coloring" as the Queen of Sheba. ()

In 2268, Captain Ronald Tracey noted that the Kohms of Omega IV were friendly enough once they got over the shock of his white skin which resembled the Yangs, who were seen as savages. ()

In the 19th century-based Sherlock Holmes Program 3A, the  hologram recognized Geordi La Forge as a "dark fellow" after observing him use the term "arch". () 

In 2368, while preparing to alter Data's appearance to that of a Romulan, Doctor Beverly Crusher noted that changing his skin pigmentation shouldn't be too difficult, while changing it back might be. ()

In 2373, several Borg drones regained their original pigmentation after their links were severed in an electrokinetic storm. ()

See also 
 Skin discoloration

External links 
 
 
 
 
 
Physiology