The rainbow spectrum of hues bathing our world holds beauty and mystery. Yet for a rare fraction of people, that palette appears far wider and richer. Thanks to quirks of genetics, some humans receive enhanced color vision known as tetrachromacy, a true superpower allowing people to distinguish 100 million shades – 100 times more than the rest rest of us.
A Numbers Game in Our Eyes
To perceive color, our eyes rely on cone photoreceptor cells tuned to red, green and blue wavelengths. The combination of signals from these three cone types underpins normal human color vision. This tri-chromatic vision provides the capacity to discern around one million distinct hues.
However, mutation can grant some people an extra type of cone cell sensitive to different wavelengths. Possessing four cone varieties instead of three boosts color perception exponentially in these lucky tetrachromats.
A Female Phenomenon
Tetrachromacy only manifests in women, as cone genes reside on the X chromosome. If a woman inherits normal and mutated cone genes on separate X’s from each parent, she gains tetrachromatic potential. Men receiving just one X chromosome have no such redundancy, so anomalous cone genes cause color blindness instead. Overall, roughly 12% of women carry tetrachromatic genetics. Of those, a small fraction tap into enhanced color sensing.
Visions of Vibrant New Palettes
What’s seeing through tetrachromatic eyes really like? These exceptional observers describe palettes alive with hues we utterly miss. Artist Concetta Antico calls it “more intense,” saying “I see colours in other colours…So white is not white; white is all varieties of white.” Leaves, shadows and human skin all reveal secret shades. However overwhelming at times, tetrachromacy lets Antico produce artworks with depth we barely perceive.
For now tetrachromacy’s rarity means most of us remain tri-chromatic. Yet perhaps through advancing genetics we may all one day access the brilliant extra richness tetrachromats enjoy. Until then, we must close our eyes and envision the dazzling world apparent to those gifted with nature’s true technicolor vision.