As the A?dans were less numerous than the descendants of the Four, their Second Millennium colonies had tended to be smaller and more Spartan, leading to a symbiotic relationship with the Camites, who tended to thrive in such environments. A?dans built colonies but Camites made them work.
In any case, the formation of new colonies and habitats during the Second Millennium had led to a phase that the historians called Isolation: the formation of racially “pure” populations. Isolation led to Caricaturization: selective breeding, pursued consciously in some cases and unconsciously in others, that had the effect over many generations of intensifying racial differences. The example cited most often was a gradual change in eye color among Moirans. Eve Moira’s eyes had been hazel: relatively light in color by the standards of black people, but not all that unusual. By the end of the Second Millennium, many Moirans had eyes so pale in color as to appear golden in strong light. On the walls of the Great Chain’s fashion stores, blown up to ten times life size, Moiran fashion models still gazed at you through shockingly yellow, catlike eyes. Because pale eyes had been a distinctive characteristic of Eve Moira, it had become thought of as beautiful and desirable, and Moirans with pale eyes had found it easier to mate and reproduce, intensifying the trait over time, to the point of caricature. Kath Two herself, no model, was frequently complimented on the lightness of her eyes, which were closer to green than yellow. But modern, appearance-conscious Moirans were frequently startled when they saw photographs of their Eve with her eyes that were merely greenish-brown.
The shift in Moiran eye color was obvious and easily documented, but the same thing, mutatis mutandis, had happened with scores of other phenotypes among all the races. Selective mating had the power to wreak impressive changes over time, without any artificial meddling. In some cases, though, racial isolates had acquired genetic labs of their own. These had been used for many purposes, usually considered benign. In some cases, they had been used for Enhancement, which meant deliberate genetic manipulation for the purpose of rendering racial characteristics more pronounced—the artificial acceleration of what was happening “naturally” in the way of Caricaturization. Sometimes this led to freaks, monsters, and disasters. But often it worked. And when its results mated within isolated groups, those isolates became more and more pronounced embodiments of their races.
The end result of all this tended to be nonviable populations clearly identifiable as inbred. So, as often as Isolation, Caricaturization, and Enhancement had taken root and run their courses, they had led either to extinction of colonies or to an ameliorative process called Cosmopolitanization, wherein formerly isolated groups had remerged with their long-lost cousins of the same race and bred back in the direction of healthy and sustainable hybridized strains.
Not surprisingly, Cosmopolitanization had flourished as the habitat ring had been formed during the most recent millennium, suddenly creating a vast amount of new living space far more appealing than the cramped, dark tori in which people had been living for the last four thousand years. The isolates, some of whom hadn’t been heard from for centuries, some of whom could not even speak Anglisky (as the Russian-inflected English, now shared by essentially all humans, was called), emerged from their holes and recombined with their extended families in a population explosion the likes of which had not been seen since Old Earth’s twentieth century. Most of the population of most of the races had thus converged on a set of renormalized racial profiles, while preserving a few extreme tribal isolate strains, variously treasured, feared, or persecuted by others of the same race.
Or at least that was how it was in Blue. Red had exhibited the same general trends among its A?dan mosaic, its hundreds of millions of Camites, and the roughly 80 percent of Julians who had decided to throw in their lot with Red. The current state of affairs between the turnpikes could only be speculated at, since no communication, other than stray signals intelligence and a propaganda channel that most people ignored, had been received from that part of the habitat ring for almost two hundred years.