viral Tumblr dress

Photo: Caitlin McNeill/Tumblr

Yesterday was a big day for the Internet. Llamas were on the lam in Arizona, and then a woman posted a photo of a dress on Tumblr.

You know what dress I'm talking about.

Whether you see it as white-and-gold or black-and-blue has become an identifying characteristic that you were likely compelled to share on social media.

Numerous news outlets have shared explanations for why some people see blue where others see white, but there's at least one person who doesn't fall into either the white-and-gold camp or the black-and-blue camp.

Most people are trichromats who see about a million different colors, but impressionist painter Concetta Antico is able to discern 100 million.

She's a tetrachromat, meaning she has four different color receptors. Most of us have only three, so when we look at a rainbow, we see seven colors — but Antico sees hundreds.

"In an odd twist of fate, the same genetic glitch that creates color-blind males may create females with better-than-usual color vision," writes Cynthia Wood in A Life More Colorful.

What does Antico see when she looks at this viral photo of the dress?

"This dress is a colored or darker version of gray," she writes on her Facebook page. "It has hints of lilac, blues, grays, pinks... not bright but subtle... it is definitely not appearing dark as in black or dark blue on my monitor. In the gold area or lace there is some gold yellow but also grayish gold brown and lighter gold beiges."

Scientists have been studying this phenomenon since 1993, and research shows that 1 percent to 50 percent of women may be tetrachromats.

Think you may be one? You can take a test to find out.

Learn more about Antico and how she sees the world on her website.

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