Cuke
The cuke (pronounced /kjuːk/) is a species of organism native to the planet of Kadis, which has a level of intelligence at least equal to that of a nonhuman ape, and which many biologists believe to be actually noetic. The fact that cukes do not seem to produce their own elaborate tools and other artifacts does not prove their innoesis, as they may simply not have reached that level of technological development yet, perhaps being the equivalent of pre-civilized human "cavemen". Because of their possible noesis, Kadis United has outlawed the keeping of cukes as pets, or their use in scientific experiments, or any other employment that would not be suitable for humans or other noetic beings. On the other hand, while to some degree protected from exploitation, cukes are not legally recognized as noetic entities equal to humans and other races, and are not granted full rights.
Cukes are found on all continents of Kadis, though they are most common in the supercontinent of Iorland, and paleontological evidence suggests they arrived on the planet's other two continents significantly more recently, perhaps within the past few dozen millennia. They are even found beneath Kadis's oceans; not needing to breathe air, they can function beneath the water much as they can above it—though they can use atmospheric oxygen as a supplementary energy source, so marine cukes tend to be sluggish in comparison to their terrestrial cousins. Cukes are particularly common within the tunnels that honeycomb the planet's outer crust, and many biologists believe the creatures were actually responsible for these excavations (though the majority opinion, albeit that of a currently shrinking majority, identifies the nelder as responsible for all such activity predating human presence on Kadis.
Description
The cuke has an oblong body, slightly larger on one end than the other, not unlike an elongate gourd. It is this resemblance that gives the cuke its name, cuke being short for "cucumber", or in this case more specifically for "sea cucumber", which animal some of the planet's first human explorers thought it brought to mind. (Along similar lines, present-day Kadians sometimes call the creatures "gherks" (pronounced /gɜrk/, and sometimes spelled "gurk"), after "gherkins", though in many areas this term is considered somewhat offensive by those who believe the beings to be noetic.) Furthering the creature's cucurbitaceous appearance, its flesh is bestrewn with irregular bumps and warts. The thing's primary manipulating members are retractable tentacles clustered at both ends, which can extend out to well over half the creature's length or fully retract to leave their tips flush with the surrounding tissue. When extended and opened, each of these tentacles ends in four splayed "fingers" with an aperture between them, though when they are retracted the "fingers" close around the center and the tentacle ends are almost undetectable as anything other than yet another of the many lumps on the body.
Coloration and ornamentation of cukes' bodies varies widely. Cukes of virtually any color are known; red, white, and green are all particularly common, but blue, brown, orange, and black also frequently occur, and even cukes of unusual hues such as bright chartreuses and vibrant magentas have been seen. More common than solid-hued cukes, however, are those of patterns. Some cukes sport stripes or bicolor spots, but more irregular markings are the rule, with blotches and mottlings and particolorings routinely occurring. Some individual cukes have become known for their odd patterns, sometimes coincidentally resembling known shapes or figures. One well-known cuke living near Thartis is called "Father Time" because of the neat hour-glass symbols on its sides. Another cuke is referred to as Celeste, perhaps short for celestial globe, after its pattern of white specks on a black field that brings to mind a starry night sky. (Some of its spots are even said to accurately depict actual constellations near Kadis, but the closeness of this resemblance is highly exaggerated.) Yet another is rather more crudely called Johnson, for a large spot on its back that bears a remarkable likeness to the outline of a human male reproductive organ.
Anatomy
At a glance, a cuke looks like little more than an illineated lump, with no apparent apertures and its only obvious appendages being its tentacles. Even those aren't necessarily noticeable when retracted. Of course, the cuke is not as featureless as it appears. Close inspection may reveal a subtle seam running down its dorsal surface. This is an opening to the os, or mouth, which leads into the creature's digestive cavity, or gut, more technically referred to as a venter. This description is a bit deceptive, however, because the cuke does not necessarily have a single gut; it has the capability of partitioning its venter into as many as six sections. Moreover, it has conscious control over which sections actually fill with digestive acids; the cuke can therefore use part of its venter for digestion and another part to carry objects safely. The cuke has no digestive tract beyond the venter; food waste is simply expelled back through the os.
Some of the cuke's systems are unusually decentralized. This applies most notably to the nervous system and the circulatory system—the cuke bears a number of scattered ganglia rather than an encephalized brain, and the cuke's blood (or the fluid that serves the same function) is pumped through its body by a network of small hearts rather than one large one. One organ that does occur singularly is the fornacula, a tough sac in the center of the cuke's body that holds radioactive minerals. When the fornacula was first discovered, before its purpose was understood, it was dubbed a "gizzard" by analogy with the gigerium of birds and certain other animals. Now, although it's still sometimes called a gizzard, it's known to serve a very different purpose; the radioactive stones in the fornacula are not gastroliths there to grind the cuke's food (except during the reproductive process, there is no connection between the venter and the fornacula, but as a power source. The cuke has developed a means of absorbing and storing energy from the gamma rays given off by radioactive decay.
Cukes use the radioactivity of their tissues not only as a power source, but for communication as well. Another organ embedded in the cuke's body, the gratilla, is able to detect gamma radiation. (Since the gamma rays easily permeate the cuke's tissues, the gratilla's internal position little hinders its percipient properties.) The gratilla can detect not only the presence or absence of gamma rays, and their wavelength and intensity, but also their polarization. AS the shielding tissues around the fornacula are able to selectively block some polarizations more than others, cukes can therefore modulate the polarization of the gamma rays they emit, and use them for communication over large distances. This modulation of polarization was not recognized until quite recently, and it was thought that cukes had no complex communication—one of the reasons many biologists were certain they were innoetic. Now, it's still not yet clear whether their communication composes a true language, though evidence seems to be pointing in that direction.
Though the cuke's other sensory organs are not concentrated in a "head", they are nonetheless present. The most visible are the numerous tiny grey eyes that speckle its body, not obvious at a glance but discernable on closer inspection. Each of these eyes individually supplies a rather poor image, but in combination they provide the cuke with adequate vision. The cuke's hearing, on the other hand, is rather poor; while there are some spots on its body that are sensitive to vibration, they are not particularly strongly so. Olfactory apparatus exist within the cavities in the cuke's tentacles.
Naturally, the drawback of the cuke's constant exposure to radioactive substances is the cellular damage that these high-energy rays can cause. Like many Kadian organisms, cukes have therefore developed a high resistance to genetic mutation. Genes hit by gamma rays in the cuke are no less likely to be altered, but the cuke's cells maintain several copies of their genes, and have molecular mechanisms to continually compare the various copies against each other and repair any that have been altered. Nevertheless, these repair mechanisms are most acvie in the most essential parts of the genome, and some less vital parts are allowed to more freely mutate. These mutations are especially common in germ cells, having as they do fewer copies of the genes, and this is, perhaps, the reason that cukes vary so much in color and pattern. Other nonessential aspects exhibit similar apparently random variation, including number of tentacles, arrangement of "warts" in the cuke's surface, and even the precise positions of certain organs in the body.
Reproduction
Cukes are hermaphroditic beings, without separate genders, though a solitary cuke is incapable of self-fertilization. More specifically, a cuke can be said to be dichogamous, spending most of its life female but occasionally becoming male. (The designations of "male" and "female" for the cuke's temporary genders are somewhat arbitrary, however, as arguably it is the effusion of the gender traditionally referred to as "male" that better corresponds to the ovum, though it is the "female" that actually bears the young.) A cuke from time to time enters a state called viratus in which one of its tentacles changes form slightly and essentially becomes a sexual organ. If this tentacle is then interfaced with the interior of the venter of an aviratic cuke (that is, a cuke not currently undergoing viratus), it temporarily fuses, whereupon it emits a cluster of gametes collected in a reproductive vesicle that forms in the aviratic cuke's membrane. This process, which is (not entirely aptly) called impregnation, takes about two hours, after which the two cukes may separate and disengage. The aviratic partner then secrets gametes of its own into the vesicle, which combine with those deposited by its viratic impregnator to form embryos.
Viratus does not occur on any regular periodic schedule, but on average a cuke undergoes viratus about every ninety days, and the state lasts for a little under three days. While a viratic cuke cannot be impregnated, it is quite possible for a cuke to enter viratus while pregnant.
For roughly 150 days, the embryos will grow and develop in the body of an impregnated cuke. During this period, the parent cuke locates and ingests radioactive minerals, which are passed through the lining of the venter and into the vesicle to be incorporated into the maturing fœtuses. (Cukes do not typically take in new radioactive matter for their fornaculae Finally, when the cuke is ready to give birth, the section of the venter nearest the vesicle becomes sectioned off, and the reproductive vesicle moves toward the venter and merges with it, expelling the newborn cukes into the partition, wherefrom they are then vented outside the body. A typical cuke birthing results in two to four young, which by that time more or less resemble the adults except for their size.
Diet and behavior
Although the radioactive sources in their fornacula provide much of a cuke's needed energy, they still need to eat, not only for energy but to obtain necessary chemicals. Cukes are omnivorous, feeding on both flora and fauna, seizing food with their tentacles, be it vegetation or mobile prey, and introducing it into their venters for digestion.
Given the cuke's ungainly form and lack of claws or teeth or other obvious natural weapons, many unfamiliar with the creatures are surprised to hear them described as (at least part-time) predators, and wonder how such a seemingly harmless thing could possibly manage to catch anything moving. The truth is that while the cuke's motion is mostly rather slow—its normal means of locomotion is a contraction and expansion of its body not unlike that of the sea cucumber from which it gets its name—its tentacles can lash out with remarkable rapidity when necessary, and are strong enough to hold prey fast and even to crush smaller victims. Moreover, glands within the apertures in the ends of the tentacles can secrete toxins capable in even small quantities of irritating flesh, and in prolonged exposure of killing. These toxins are more effective against the Kadian native life they evolved to attack, but alien beings such as humans are not immune to them. As for their defenses, the cukes' tentacular toxins work to ward off creatures that would prey on the cuke as well as they do on the cuke's own prey, and if a cuke really needs to escape a threat in a hurry, it is capable of pulling itself along with its tentacles, or even raising up on tentacles and awkwardly "walking" on them for short distances. This means of movement the cuke rarely uses, because it is extremely tiring, but is much faster than its normal locomotion and is often useful in emergencies.
Cukes live in large communal tribes, numbering from a dozen to several hundred. Young birthed from any tribe member are raised by the tribe as a whole, although their parents recognize them and typically give them especial intention. Most matings take place between members of the same tribe, though intertribal dalliances are not uncommon. It's far from unknown for a cuke to decide for some reason to leave its tribe and join with another, though if it does so the members of its old tribe thereafter generally disregard its past allegiance and treat it as they would any other member of a foreign tribe.
Off Kadis
Cukes are very seldom encountered off Kadis—not being considered fully noetic, they aren't offered positions or passage on ships leaving the world, or allowed near duplicators, but being considered more than simple beasts they are not permitted to be taken off the world against their will either. Nevertheless, a few rare cukes have made their ways to other planets. Some have stowed away on ships for various reasons, others have been smuggled off planet as curiosities or mascots (and perhaps escaped later to make their own way on new worlds). Perhaps a very few cukes have been taken in by individuals or groups who despite the current consensus opinion—and their inability to easily communicate with them—see the cukes as the equals of any other noetic entities, but this is an extremely exceptional occurrence.