Monkey is a common term, used indiscriminately for two otherwise unrelated groups of mid-sized Old Earth primates that were neither humans or other apes nor early primates such as the "prosimians" (lemurs, galagos, etc.). One group was native to Africa and Asia; they had bare "sitting" pads on their buttocks, sometimes brightly coloured, and included both terrestrial and fully arboreal forms; their best-known varieties included baboons, macaques, and langurs. The second group was from South America and Central America, and was exclusively arboreal; notable species were the howler, spider, and capuchin monkeys. Though numerous and successful prior to the advent of humanity, most species were extinct in the wild by the end of the Information Age due to predation and habitat destruction by humans. Many were entirely extinct, and existed only as records in gene banks, though some were preserved as captive populations. They exist now primarily on Old Earth, where many or all the original species appear to have been lazurogened and restored to their original habitats, and in reserves established by the Institute For Primate Provolution, in artificial habitats at Solsys and on its planetary preserves at Ao Lai.
Monkeys were not popular provolution subjects in the Interplanetary Age, mostly because the impulse to create primate provolves waned after the advent of the first ape clades, and partly because early monkey provolves did not do well in human society. Many of them were too shy or too aggressive by human standards, and though the genetic engineering of the times could increase overall intelligence it was less successful in its influence on particular personality traits. Later attempts to compensate often produced individuals or clades little different from baseline humans in appearance and behaviour. However, there were two minor clades, one based on the capuchin monkey and the other based on the common rhesus macaque. The sapient capuchins in particular proved to be a hardy if somewhat reclusive spacer clade. The discovery, by the group that was later to be known as the Institute For Primate Provolution, of a cache of monkey and other primate genetic information, led eventually to a proliferation of monkey provolves, but monkey derived provolve clades have never been as numerous as other mammalian provolves.
Sub-sophont monkey-derived species are part of the maintenance crews of many habs in the Zoeific Biopolity, and are moderately popular in that role in other places as well, particularly if they are also physically attractive. Some of the more spectacular extinct species, such as the giant baboons (Dinopithecus species) have been popular subjects of lazurogenic attempts, and are found in various game parks. Monkeys of all sorts (baseline, lazurogened, splices, and tweaks) form part of the biota in many habitats and on many terraformed worlds across the Terragen Sphere.
Grafts from monkey genes are fairly common in the human nearbaseline population, though they usually code for useful traits that are not apparent to casual inspection. More obvious are cosmetic mods, such as those for unusual golden, orange, blue, or true white skin colour; these traits are usually derived from the genome of the douc langur, or the mandrill, or for some of the more attractive patterns of fur in some nearbaseline subclades. Persons carrying such relatively minor mods are not considered true rianths. In fact monkey rianths are rather rare since most often they are interfertile with the rest of the human population and do not form separate clades. Some human-derived spacer clades have prehensile tails modeled on those of the South American monkey species, to supplement their prehensile feet. These are distinct, and usually do merit separate clade status (though they are usually called tweaks, not rianths).