Game Biology: Shine Bright like a Shine Bug (Oxygen Not Included)
Examining the glowing Shine Bug critter from the game Oxygen Not Included, how bioluminescence happens in real world animals like fireflies and a neat lil snail called Quantula striala, and how bioluminescent animals use their gifts to meet and/or eat each other.
Game and music source: https://www.klei.com/games/oxygen-not...
Abbreviated transcript:
The base builder game Oxygen Not Included provides a fascinating look into an alien ecosystem constructed by the designers of game studio Klei Entertainment. Among the building blocks of the biospheres generated in this game are critters - animals found roaming the asteroids which your duplicants are colonizing or synthesized from the printing portal. Today we’ll be shedding light on the shine bug.
The shine bug is a lightbulb-shaped critter which can be found floating around open areas in temperate environments in the game. Their main benefit to duplicants is that they give off light, which increases the decor stat around them, making the environment more pleasant and so reducing the colonists’ stress. The light emitted by shine bugs differs from light given off by lightbulbs or other power-dependent sources in the game because it does not give off heat. The ability for a biological organism to generate light is called bioluminescence.
Shine bugs consume phosphate; phosphates in the real world are a family of ores commonly found in sedimentary rock. Phosphates contain the chemical element phosphorus; organisms use phosphorous for many essential functions, including enzyme activation, gene transcription, and building bones and teeth (2). In this context phosphorus is interesting to us because it is chemiluminescent - it gives off light when exposed to oxygen. Just like the shine bug, phosphorus does not give off heat when emitting light this way.
Shine bugs are attracted to light sources, and the database entry for shine bugs specifies that they “emit a soft light in hopes of attracting more of their kind for company”. One well-known real-world corollary to this behavior is fireflies, which contain a light-emitting compound called firefly luciferin; fireflies are able to control whether or not they give off light, and create flashing patterns, by controlling whether or not oxygen is flowing into the light-producing organ in their abdomen, called a lantern (3). Unlike fireflies however, shine bugs shine constantly, so they do not seem to have this sort of control. Females of the firefly Genus Photuris mimic mating flashing patterns of other species to attract and prey on unwitting males as meals; in turn, males of the Photuris species also mimic the flashing patterns of other species males, either for the same purpose or to attract Photuris females (4).
Although Shine nymph eggs do not give off light in the game, there is a real-life bioluminescent species’ eggs that do: this is Quantula striala, the only known bioluminescent land snail. Quantula striala produce a faint greenish light from what’s called their “organ of Haneda”, named after the researcher Dr. Yata Haneda, who discovered the snail’s bioluminescence in 1942 (5). Their eggs glow continuously, and adult Quantula striala snails produce dim flashes of light while moving. Some species of firefly eggs and larvae also glow.
There are several differently-colored versions of shine bugs in the game. This is another correlation with real life fireflies; while most fireflies give off a yellow-green light, some species such as Phausis reticulata, also known as the “blue ghost firefly” of the Eastern United States, give off different colors of light, such as bluish white in the blue ghost’s case (6).
Bioluminescence is useful to some real-life animals as a way to deter predators from eating them; this is known as aposematism. The glow of firefly larvae and biolumniscent millipedes has been shown to consistently deter predators such as mice which would otherwise feed on comparable prey (7, 8). One might think that an animal glowing would make it more prone to being eaten since it makes the animal easy to spot, but the opposite seems to be true; in the case of the biolumniscent millipedes, much like poisonous frogs are brightly colored, the millipedes’ glow functions as a signal of their toxicity, as they secrete cyanide.
WORKS CITED:
1) https://www.sciencedirect.com/topics/...
2) https://ods.od.nih.gov/factsheets/Pho...
3) https://www.scientificamerican.com/ar...
4) https://www.ncbi.nlm.nih.gov/pubmed/1...
5) https://www.malacology-asia.com/index...
6) https://www.sciencefriday.com/article...
7) https://link.springer.com/article/10....
8) https://www.ncbi.nlm.nih.gov/pmc/arti...