Lacosian society is geriatocracy. The five eldest Lacosians comprise a High Chorus lead by a High Lord of the Lacosian Chorus wielding absolute authority. Other prominent roles within the Chorus are the Sacred One, the Keeper of Justice, the Elder of Ages and the High Seeker. The exact nature of these roles is unclear.
Lacosians are no taller than a metre in height with skin tone ranging from celadon green through oxidized copper to drab yellow-green. The broad, flat face and thin limbs have the appearance of a bipedal Terran toad. There is no apparent sexual dimorphism.
Regardless of age, Lacosians have juvenile tendencies. Hide and seek is a popular game even amongst adults.
Gam, a sort of diagnostic and maintenance device, are distributed throughout the sphere and relay information to nearby workers. Elder Lacosians can communicate with gam that are quite distant. Given the mass of material that can exist between a gam and a worker, it is likely that gam communicate as a network although this has not been definitely proven.
Lacosian work individually or in small teams. Most workers are called lacosniir with supervisory workers addresed as jekaal. Work crews may be called porenzek, a melody. More broadly, Lacosian society is a collection of melodies forming choruses or choroi.
All Lacosians are telepathic but retain spoken language as their primary method of communication with each other. The language is heavily symbolic; melodic fragments represent entire phrases and concepts. A second layer to the language is mathematical in speech and script. It is a verbalization of the language used to communicate with the sphere. Aurally, it is a melodic, musical language. Lacosians can sing multiple tones simultaneously producing harmony, overtones and interference.
Despite living below the surface, Lacosians recognize the artifical day-night cycle of the sphere. Juvenile Lacosians receive a purple rod, or shard, at about 25 cycles of age. One cycle is 500 days (1.37 Terran years). At 75 cycles, they become lacosniir, workers and are assigned to a work crew. A Lacosian is considered an Elder at 500 cycles. By this time, an Elder has mastered the entire toolkit required to maintain the sphere and communicate directly with gam and the sphere without the need to use rods as a medium.
Builder technology is utilized by Lacosians as a series of rods. Rods are hollow, hexagonal cylinders whose crystalline structure form a sort of circuitry. They are operated telepathically and have varying function based on color:
Builder technology is wormhole-based. Matter is manipulated with the creation of micro black holes and white holes. For example, matter creation is drawing material from a black hole through a white hole and modifying it. In contrast, replicator technology reorganizes matter in situ. Once opened, a white hole can provide as much energy as contained in the black hole to which it is connected.
Lacosian oral tradition retains several details of the history of their people and the sphere itself. Lacosians originate from the eighth planet of a star names Lacos collected by the Builders as material for the dyson sphere's construction. The Johvan populaton was present within the sphere as indentured laborers. Lacosians were prolific and easily conditioned through breeding and genetic engineering for use by the Builders. Telepathic ability was either nutured from early Lacosians or introduced by the Builders. The shell of the sphere was completed by a combination of Johvan and Lacosian workers. As the completed sphere was being terraformed, the Builders abandoned the project without explanation.
The Builders introduced a genetic condition called Rasp. It inhibits reproduction and is immune function causing premature disease and death. As a result, few Lacosians survive adulthood. Medical research culminated in a therapy to reduce the effects of Rasp in 2411. Success is variable with some patients experiencing no alleviation of symptoms and others cured. All Lacosians are genetically disposed to the condition and may be instigated by environmental conditions. It remains an ongoing area of research. Since 2411, the Lacosian population has nearly doubled to an estimated 60,000 individuals. Given the sheer size of the Dyson Sphere, it is remarkably rare to find a Lacosian.
Lacosians are friendly to Federation representatives although there is no active diplomatic relation. Lacosians had not been seen by Johvan in centuries and were considered more myth than reality. First contact occured between Starfleet officers and Lacosian workers in 2408. Encounters between the two societies are friendly although Lacosians focus on their work and will teleport without notice during a conversation. There is no established method of contacting a Lacosian. Finding a Lacosian is a matter of luck.
Communication is possible with a unvisersal translator. Lacosians carry a "voicebox" on the left-rear side of their heads to communicate with each other and non-Lacosians.