Aalor is a class-M planet with surface gravity 1.1g and a standard atmosphere. It has little tectonic activity, resulting in many great plains which stretch across the surface and fewer salts and metals in the crust. While there are no mountain ranges, there are some spectacular volcanoes. It has many lakes and inland seas, with water covering to 65% of the surface area. The local year is 190 standard days; the local day is 26 standard hours.
The landscape varies from many fertile river valleys to the enormous plains which divide the globe. There are few deserts but many swamps. The wildlife are not very distinctive, with similar species across the globe. The plants are generally very tough, with tall grasses and thin trees dominant. The animals are variations on warm-blooded dinosaurs, marsupials, and avian species. The Y'prrg themselves stand out somewhat as more physically advanced than other species on their planet.
They have carapace-like ridges on their skin, going down their spine and along their arms. In males, on the forearms the ridges expand into barbed quills which have an irritant poison secreted into them. These quills generally lie flat against arms, sticking out a bit at the elbow. By muscles they can be raise these quills to a 45 degree angle as a painful weapon.
Their internal organ structure is significantly different, but functionally similar to Terran's except that there is slightly more redundancy in organs like the liver, spleen, and such.
They do have a notable metabolic difference from Terrans. They are capable of a {\em surge} of energy where they have perhaps twice their normal strength and speed for a period of 8-14 seconds. This causes immediate exhaustion, disorientation, and cramps for the next several minutes.
They advanced considerably in technology under an essentially feudal society. While they had gunpowder, and sailing, and astronomy, the lack of organization made these inventions not as revolutionary as they were on Terra.
When it did take over, suddenly an enormous number of nearly-built inventions took over. Mechanical computing, airships, rockets, radio, and more rapidly revolutionized how the world worked. The minds of the people were now thoroughly modernized, and much of societal structure was overturned in welcoming in the new changes.
This was the era of women's suffrage, of democracy, and of freedom of speech. Various grassroots cultural revolutions accompanied the technological revolution. While few of the ideals were fully met, an overwhelming optimism made up for the lack.
About a century after the beginning of the Revolution, they were enjoying nuclear power and the start of space exploration. While several local wars had marred the picture, the new World Concordium was growing in power as a global peacekeeper.
Then the Kzinti invaded.
The population was too stunned to react at first. Local forces which tried to resist the Kzinti at their landing sites were annihilated, and many of the other governments refused to believe the reports. Once in place, the Kzinti began to demand dues from other countries.
Forces which resisted were largely treated as sport: hunted, captured, and eaten. The remaining population suffered under increasingly oppressive martial law.
In Y139, the Federation took over the area of space and offered the Y'prrg membership. Adrift and lost, the Y'prrg latched onto this as a way to fight back. They offered additional services and people to aid Star Fleet in opposing the Kzinti.
A younger generation is taking a more cosmopolitan view of their place in the galaxy, and are trying to increase contact and trade with other Federation members.
Few large agencies remain to try to pick up the pieces. Large governments have largely been abandoned in favor of local government. Several bloodless revolutions broke up the larger nations into factionalized states.