Extinct Civilizations  As Humans moved outward into the Local Neighborhood, a shockingly large amount of evidence for long vanished cultures began to be accrued, some of which dated back billions of years, and which had apparently risen to fantastical heights of technological achievement.  Other ruins offer little information on the nature of their vanished owners, beyond the fact that they had once existed.
  • "Angelics" (Primocogitarius sapiens sapiens): The earliest known civilization, which had expanded to cover most of the Milky Way.  Extant from 6.82 to 4.52 billion years ago, the civilization likely slowly fell victim to cultural senescence, eventually leading to the isolation and extinction of the species.
  • "ArcBuilders" (Primus condoquadrivius):  This is the species which created the ArcWay network, which tied together their interstellar polity within the Local Neighborhood, a polity which existed from 800,000 to 120,000 years ago.  That polity vanished literally overnight, and for completely unknown reasons.  The ArcBuilders (or "Builders") were adapted to various Gaian worlds, although they seem to have rarely expanded to such worlds not orbiting G-type stars.
  • Arim-Ojefo-Joi:  An extinct sophont species, native to a Dunwalli ringworld.  However, they utilized the ringworld's resources to such a degree that the biosphere collapsed, causing the extinction of all life on the structure.
  • Dunwalli (Dunwalli sapiens sapiens):  The dominant species of a now extinct galactic civilization, extant from 1.35 billion to 600 million years ago.  Evidence suggests that they first arose on a world either seeded or otherwise terraformed by an even older species, possibly even the Angelics.  They are known for the apparent large numbers of Bishop rings left behind, most of which are either senescent or completely abiotic.  The polity is believed to have fallen due to heavy dispersal over time, and the loss of contact and interrelationships necessary to maintain their technology.
  • Eiyogsha (Immortalus mentis eiyogsha):  The Eiyogsha civilization was extant from 588 to 363 million years ago.  However, the species eventually perfected the means to extend their lives, and over time individuals began to integrate themselves into massive spacefaring machines - starships, for all intents and purposes.  Reproduction ceased, and slowly entropy has reduced the species to near or full extinction.
  • "Lost Civilization" (Homo sapiens sapiens):  A former polity of Humans, centered on Earth, extant from roughly 11,000 to 7500 BCE.  The polity was culturally and technologically provolved by the Sivata, who aided them in spreading through the ArcWay network and colonizing a number of planets.  With the collapse and apparent extinction of the Sivata, the Lost Civilization fell as well.  The extrasolar colonies would devolve culturally to today's Lost Colonies, while those members left on Earth slowly vanished through a cultural senescence, with some pockets of the culture surviving in disparate regions of the planet.  The last remnants vanished when a combination of sea level rising and tsunamis submerged their primary center of civilization.
  • Sivata (Sivata sapiens):  A species adapted to GaianContinental worlds, and which had developed an interstellar civilization within the Local Neighborhood based solely on travel through the ArcWays.  Their civilization thrived from 16,000 to 10,500 years ago, and seems to have fallen within a matter of days.  The species itself is thought to have gone extinct in the same amount of time, although why remains a major mystery.  The Sivata had colonized the Earth during their period of exploration and expansion, and are responsible for the dispersal of several populations of Humans throughout the Local Neighborhood, via the ArcWays.
  • T'chebsoni:  An extremely large and terrestrial sophont species, native to the world of Phione IV, orbiting Beta Comae Berenices.  When first encountered, the species was a migratory species with minimal tool-use, and were initially believed to be little more than animals.  However, the discovery of their rich, sub-vocal language revealed their true nature.  Indeed, after contact, they adapted quite naturally and quite rapidly to Human-introduced technology, to the point where they had begun to experiment with travel (with Human aid) in their own solar system.  The species was wiped out, however, by the Dominion during their short-lived but intense program of multi-species genocide.
  • T'zeche (Tzechis peregrinus sapiens):  The dominant species of a now extinct galactic civilization, which had been extant from 747 to 384 million years ago.  The species apparently evolved on a meta-stable Dunwalli ringworld, and which spread out across the Galaxy via a beamrider network.  This network created a series of civilization "nodes", with large regions of almost no civilization between them.  The polity failed when the species mass-migrated out of the Milky Way for unknown reasons.  It is possible that the T'zeche still exist, in some form, in an extra-galactic milieu.
  • ZaFarKumor:  An extinct sophont species.
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Pre-Agricultural Civilizations  It seems to be a general rule of development that intelligent species exist as hunter gatherers far longer than they do as a technological culture.  Most of the intelligences out there could be considered to live at a "stone age" level or less.  The leap to discovering agriculture, animal domestication, and the establishment of permanent settlements may well remain out of reach for most, as environmental effects could see them extinct before they have a chance to develop further.
Post-Agricultural Civilizations  The development of agriculture opens the door to a more sedentary way of life, removing the need to travel great distances in the search for food.  Permanent settlements develop, and this leads the way to writing, more advanced religion, government, city-states, and empires.  A civilization could exist within this range of development for many thousands of years before technological advancement makes it less vulnerable to environmental forces.  As such, this level of development is also quite common.
  • Children of Kastiel:  A species of Human heavily genetically modified in order to survive the harsh conditions of their homeworld, Kidian, orbiting Omicron-2 Eridani.  A Lost Colony in origin, it is believed that the originators of the species modified themselves following the fall of the Sivata and the closing of the ArcWays.  The Children of Kastiel are a highly robust species, in possession of a culture deeply seated in concepts of honor, ritual combat, and the attainment of spiritual equality with nature.  When first encountered, their culture was divided among many different regions, each one based on a rigid feudal caste system.
  • Devasnid:  A species of Human heavily genetically modified, and native to the Lost Colony world of Kelari, orbiting 107 Piscium.  The modifications are believed to have been performed some time after the fall of the Sivata and the closing of the ArcWay network.  indeed, the planet's entire ecosystem seems to have been modified and carefully terraformed, resulting in a ecological balance of predators.  That is, everything on this planet hunts everything else, with only a small minority of creatures being completely herbivorous.  Curiously, the planetary arrangement itself seems to have been arranged.  The Devasnids themselves are divided into two distinct subsets, the male and female.  The males are often of a somewhat lower intelligence, inclined to violence, while the females are quite intelligent and capable of killing via a set of poisonous spurs in their wrists.  When encountered, the Devasnids existed in one small region, at a quite low level of technology and cultural sophistication, but were nonetheless considered to be the planet's apex predator.
  • Igii:  A sophont species located on the world of Igom, orbiting the star Tau Ceti.  This species is a heavily provolved form of Terran feline, the genetic work apparently performed by both Human and Sivata agents.  However, the Humans of this world either died out, or removed themselves at some point, leaving the Igii to develop naturally.  When encountered, they had developed into a remarkably Earth-like feudal society (some speculate that this was somehow "built into" their genetic make-up) that was just beginning to shift from a combative system of Houses to a scientifically-orientated culture.
  • "Tripods":  A sophont species native to the star HD 199476.  When encountered, they existed within a fairly primitive, pre-industrial society, largely confined to a single continent.
  • Tsalos'ey:  A sophont species, commonly referred to by Humans as "Bugs".  Their native world was seeded by the Tsubar'ey during their Third Civilization with biomes from the Earth of that period.  At some point thereafter, the world was abandoned as the Tsubar'ey plague swept the Galaxy, driving the patron species into their Third Migration.  in the intervening time, a species of Eurypterid arose to pre-sentience.  In recent millennia, these creatures were further aided by the Tsubar'ey, and have achieved a relatively advanced, pre-industrial culture.  The world remains quarantined by request of the Tsubar'ey.

Post-Industrial Civilizations  The rise to technological advancement often comes from a few remarkable individuals, or even accidental discoveries.  But once they occur and gain a foothold in the local culture, that culture begins to take great strides forward.  Very few civilizations remain in this state for more than 2,000 years or so, and some may advance much further in only a couple of centuries.  Marked by the rise of advanced metallurgy, mass production, rising education, and the use of fossil fuels, these civilizations are the first to begin impacting their world and influencing its development, rather than the other way around.

World Civilizations The often swift growth of technology will almost inevitably lead to a planet being united under one or more major influences.  On Earth, the exchange of information, globe-spanning transportation, and other similar means lead to the concept of the "global village".  Such civilizations need not act in unity, of course, for there remains room for many nation states to vie for power.  The greatest threat to these civilizations is global war, although their impact on the planetary environment could be cause for major concern as well.  World civilizations, nevertheless, often present one dominant voice that can be - just - heard by those who might strain to listen, far beyond the surface of the planet.
System Civilizations  Few civilizations expand beyond their solar systems.  Whether they choose to remain confined because of the inherent difficulties of interstellar travel, or they lose their interest in seeing what is beyond, they nonetheless remain advanced enough to take advantage of the resources inherent in a solar system.  Relatively speaking, these civilizations are easy to detect at interstellar distances.  However, they are still vulnerable to extinction; cultures who have taken advantage of a system's wealth and which later withdraw back to their homeworld will collapse under the material demands of their society, which can no longer be met.
  • "Moon Men" (Homo sapiens sp.):  A subspecies of Human, genetically bred in the old Lunar nation of Da-luo-tian, and specifically adapted to the low-G environment of the Moon.  This species remains extant, and has spread throughout much of the Solar System.  Off-shoots of the species have also spread to micro-gravity environments throughout the Solar System.
  • "Iskanderites":  A sophont species indigenous to a ThioGaian world, Iskander, orbiting Psi-5 Aurigae, and which had just begun to colonize their solar system when first encountered by Humans.
  • Urgchitsitnik:  A sophont species at the star HIP 109084.
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Interstellar Civilizations  Very few species will move beyond the confines of their solar system, most of the time due to the great initial expense in materials.  It is far easier to expand throughout a solar system, which provides a huge amount of space and resources.  A species may reach another star, only to either retreat, or to fail and never try again.  Those that become true Interstellar Civilizations not only establish successful presences on other worlds, but lines of communication between these colonies and the homeworld remain unbroken.  Even so, most never spread to more than some of the closest stars over several millennia.  A very few will continue to spread, however, either managing to maintain a tenuous cohesiveness with the other colonies and the homeworld, or they will lead to new branches of culture and civilization.
  • "70 Virginis Species":  Native to the EuPelagic world of Chinlé.  When encountered, they had become a fledging Interstellar species, tentatively colonizing a small number of surrounding stars.
  • Aagüla (Methanae eflo sapiens):  The Aagüla are the dominant species of the so-called "Red Dwarf Empire", a polity located within the Local Neighborhood, and extending to within only a few light years of Sol.  it was founded 216,000 years ago, although its growth is slow due to the deliberate and methodical nature of the species.  Native to Asimovian Type worlds, the species was provolved by the Tsubar'ey some 2 million years ago, and had at one point lead a millennia long war against their overseers, called the Local War.  While the conflict was resolved, the Aagüla remain reclusive and often openly hostile towards all alien species, including the Tsubar'ey and Humans.
  • "Bugs Province":  Transplanted populations of the Tsalos'ey, moved by the Tsubar'ey, and technologically and culturally provolved until they established themselves as an interstellar polity. They are located well beyond the Local Neighborhood.
  • Oswagii (Oswagii sapiens):  The dominant species of the interstellar civilization known as the Union of Synchronized Systems, located within the Local Neighborhood, and which was founded some ten thousand years ago or more.  The species is adapted to various Gaian type worlds, and despite their technological advancement, they often practice high levels of natural conservationism.  However, this also often creates deep conflicts within their own culture.  The species is naturally inquisitive, and exists quite peacefully with Humankind.
  • Satlek (Satlek sapiens):  The dominant species of their own interstellar polity, located within the boundaries of the Local Neighborhood, a polity founded some ten thousand years ago or more.  The Satlek are an ammoniagenic species, typically found on Amunian worlds.  Their relations with other interstellar polities, including the League, is cool but decidedly non-hostile.
Galactic Civilizations  These are the apparent pinnacle of cultural advancement.  Through whatever highly advanced technological means, the species will manage to create a unified polity that spans not only its own local region of the galaxy, but a good chunk of the galaxy as well.  The most advanced that have been known have spread from one end of the Milky Way to the other.  These civilizations often have technological means at their disposal which seem, even to interstellar polities, almost magical.  At their height, these civilizations may exist in an abstract manner, lacking any traditional governmental of social structure, and yet remain quite cohesive.  Others may simply begin to fade, apparently having reached some sort of cultural "weariness".  Evidence points to some extinct Galactic Civilizations as having simply allowed themselves to disappear, their drive to explore and advance even further gone.