Last week, news came that the great emoji disparity would finally be addressed: In Apple’s next version of its phone and desktop operating systems, users would be able to type emoji people of color. Most humanoid emojis previously had white skin by default—now they could be one of six tones determined by the Fitzpatrick Scale.

But skin tone, say some, is not enough.

The redhead-advocating website Ginger Parrot has launched a petition advocating for a ginger-moji.

“If you say you're going to diversify, why not add a few red-haired emoji in the mix?” asks Emma Kelly, the site’s proprietor. “Natural redheads may be rare at less than two percent of the world's population, but that is 138,000,000 iPhones waiting to happen.”

Kelly isn’t the only advocate who says hair is the next frontier of emoji diversification. Writing at the Guardian, Rhik Samadder noted that there are no emojis for beards or afros. Survey the list of humanoid emojis, and the hair is mostly black, brown, and straight.

Kelly and Samadder’s pleas are half-jokey and a little self-aware, but they hit upon an important truth. There is already an emoji, one that has long predated the newer diversification efforts, titled simply “Person With Blonde Hair.” Blond-ness, in other words, has been recognized by the Unicode Consortium, whichnames emoji. Oughtn’t Unicode recognize gingers, curls, and frizz?

These petitions illustrate an unfolding issue for Unicode. In its little pictographs, the Consortium has chosen to illustrate the vast range of human difference mostly through realism. There are black people and blond people in the world, so there should be emoji that are black and blond. (This fealty is something that many commentators, including me, implicitly called for before the new skin tones were released.)

But there are many other types of humans too, obviously, and they exist in infinite gradations. Unicode, meanwhile, is a technical system with discrete possibilities. What kind of human difference should Unicode include? There are countless kinds of humans, after all—but only 700 or so emoji.