Some Sapient Aliens

 The Flourishing Void is my own take on "optimistic sci fi." I'm going for mostly hard sci fi with a few "big lies." Maybe I'll make a post about that sooner or later.

These are basically citizens of the Galactic Community, with some effort you can sort of squeeze yourself into the right mental states to understand their own instincts and point of view, and they can for you. There's aliens that are much weirder than this, but this post is long enough as it is.

For all of these I have yet to put significant thought into the actual biochemistry of them, though that's definitely something I plan to do in the future. So expect possible changes to any references to fun biochemical weirdness. Crustaceomorphs are kinda the exception cuz its part of their thing that they're biochemically compatible with earths biosphere, in a case of sheer cosmic coincidence.

Also included is their perception of humans, explored through some metaphor.

Chuuls from D&D look like scrawny, monochromatic
Crustaceomorphs with too few limbs.

1. Crustaceomorphs

Nicknamed "humanities twin" despite their considerable number of differences. This is because they were the first higher lifeforms humanity actually managed to contact, and due to sheer cosmic coincidence were at essentially around the same capabilities, technology-wise. Further similarities exist. They essentially filled the niche of "social troop-forming organisms descended from tree-analog dwellers" leading to similar baseline instincts. Shockingly the majority of their biospheres biochemistry is actually compatible with earths, though "cross-contamination" is still of little concern due to subtle differences that mostly impact pathogen development.

The cooperation between both Homo Sapiens and Crustaceomorphs was swift following first contact. While both were willing to cooperate and communicate, they did not have any way to know if other species would. Though these fears proved to be mostly unfounded, this initial goodwill proved well-placed for both species, as most polities involving one almost inevitably involve the other in the modern day.

While cultural details could continue from here, there is only limited space on the internet to put entries, and the Crustaceomorphs have a cultural landscape every bit as rich and diverse as humanities and all other species in this list, and yet completely distinct from them.

Physiologically they are quadrupedal, possessing two additional limbs for fine manipulation, and two more "pincer" limbs for when force and strength are necessary. The "head" structure contains sensory organs, including a number of "feelers" that engage in somatosensory and chemoreceptive roles. Their exoskeleton consists of several layers, the outermost being formed of chitin and the inner layers giving way to calcified tissues akin to human bone. Internal musculature is ring-shaped, and can both push and pull with the same muscular structures, leading to an organism overall more robust and strong than their human companions.

Perception of Humans: Soft, fragile, weak and impossibly graceful. Like a person between molts, but even more so. Faster too, though stamina falls within normal range. They are singing by default, when they try to speak your language (what of it they can speak) it sounds painful for them, though they try so very hard. They seem like they should fall over the moment they try to move, and for a moment you think they are falling and your hearts skip a beat, but then they land perfectly and are already on to the next fall.

Anosteous Sapiens are like if Sea pigs were also elephants, snails and trees. 

2. Anosteous Sapiens

At first glance the name "wise boneless ones" brings to mind organisms like the Octopus or Slug, but incredibly intelligent, a staple trope of Sci Fi. The Anosteous Sapiens, however, are far less "amorphous" and "wet" than these organisms, as tough structures within their biology are formed via cells that possess analogs to "cell walls" rather than via typical biomineralization. This is a feature of many ambulatory organisms of their biosphere, as for a significant portion of its early history, typical minerals useful for the biomineralization process were nearly totally absent from the biosphere, only entering during subsequent collisions with minor celestial bodies.

This means that most hard tissues in their body are actually composed of cellular structures. An example consequence of this is most organisms are able to regrow and/or heal teeth and claw analogs without worrying about needing to regularly "file them down" so to speak.

Physiologically, they resemble something akin to a three meter long, meter tall opaque and skeleton-bearing analog to the "sea pig", possessing a large cephalothorax as their primary bodily mass, with ten blunt "legs" for movement. Internal musculature allows them to move fairly swiftly for their size, but still slower than a more gracile organism would be capable of.

Eight sensory tendrils closer to the top of the head, resembling eyestalks of snails but including chemoreceptive and audio receptive organs, allow them to percieve a 360 field of view and lend themselves to audio-spatial sensing as well. Twelve manipulator tendrils tipped with a dexterous "cup" akin to the trunks of proboscideans, line the "mouth" of the organism. Finally, four radula are are contained within the "mouth" for grinding and processing food. The numbers provided only reflect an average, as approximately ~30% of their population possesses an unusual number of these organs, and of these ~83% possess more than the standard number, seemingly a bias that was selected for historically.

Their niche could be described as "herd scavenger-grazers." Historically living in herds of hundreds to thousands, with a fairly clear competitive hierarchy, one would expect their societies to trend towards hierarchical despotism, and this does seem to be the case throughout history. However, modern Anosteous polities trend towards a more collectivist bias, forming large migratory communities. This has occurred following a relatively unstable period in their political landscapes, which led to a disillusionment with existing structures.

Perception of Humans: Like if a small and thin tree with too few branches was a person, faster than you, and moved around by acrobatics all the time. Weirdly inflexible digits on the upper manipulator limbs, and a weird inflexible orifice for feeding. Restless, like someone high on a stimulant. Their eyes flick around like they can't focus on one thing at a time, like to get the full picture of what's going on they need small snapshots every few seconds. Their voices are choppy, though some of their languages are a bit more (or less) so. This makes them seem almost like they're constantly ending their statement, and then beginning it again. Despite this they're just as thoughtful as anyone else, they see their experience as seamless and it gives interesting insights.

Coral Hives are called that for a reason. Much of their population is sessile support structures
that look a bit like corals or barnacles. Mobile workers vary in appearance too.

3. Coral Hives

Eusocial organisms with a complex life cycle, consisting of sessile and mobile morphs and colonies that differentiate based on chemical and genetic signals, as well as possessing eusocial caste differentiation. One of the most alien species that still acts as standard citizens of the Galactic Community, though the vast majority of their species is not sapient.

The sheer complexity of their life cycle is astounding, but the basic "larval" form is a radially symmetrical organism with a central "lobe" of sorts, the whole organism being roughly a fingernail in size, though eventually reaching up to a fist in size. Bilateral symmetry is sometimes introduced later, in addition to greater sizes depending on the caste.

The typical "Citizen" of this species is one of the sessile "Queen" morphs and their support-colony, ironically acting as both a controller and a reproductive caste, in contradiction to the standard earthly eusocial norms. Per Galactic Community standards, the non-sapient members of the hive, as well as its sessile structure, are considered extensions of the Queen, and extracting them from this is seen as morally equivalent to extracting a brain and placing it in a support structure bereft of the ability to manipulate the environment.

The "Queens" resemble a half meter tall "barnacle" of sorts, with feeding and reproductive orifices dotting the base, and a series of sensory and command structures extending from the top, like a tree of sorts. These "topmost" structures are modified limbs and sensory structures, the process of metamorphosis is quite extensive.

Queens command drones via pheromones, electroreception, photon and sonic signals, and may have other means as well. The sheer complexity of their communication and life cycle, as previously mentioned, has led to many theories regarding the "Coral Hives", further spurred on by the extensive ruins in the regions near the center of their space, including their own home-world. Some of these theories include that they are of artificial origin, though evidence of this is sparse to nonexistent.

Coral Hive culture is exotic, even by the rather broad standards of the modern day. To them, other species seem as if they are hyper-developed sub-units that have grown into fully fledged people, so the feeling is somewhat mutual. Though not a common sight by any stretch (their "nomad" population consists of a bafflingly small few hundred billion), they remain a staunch member of the Galactic Community, their "nomad" population often serving as valuable members of a crew, their hives being able to use their smaller units to get into very small spaces for repair and surveillance. Their more habitat and planet bound populations often aid with construction and repair in a similar capacity.

Perception of Humans: An entire species of disabled queens, who all act as each others workers and create technology to act as prosthetics. They are so bereft of basic capabilities that they need entire prosthetic clonal worker complexes (buildings and vehicles) to do basic tasks. They are almost insensate, struggle to make even the most basic concepts understandable to each other, lacking every capability that a worker morph could provide. And yet they work together in ways that we struggle to. Each one of them is a queen and a worker of each other. We could learn something from that.

Vitaegel anatomy is biochemistry. Its kinda like this, but uses
different shapes, because its not earthly life. Source.

4. Vitaegel

Multicellular life is not the only path towards complexity and, ultimately, awareness. Some life takes a different path. Slime Molds on earth are an amalgamation of countless individual amoebic organisms that have merged into one enormous cell for the purposes of movement, nutrient acquisition and overall protection.

The Vitaegel are similar, though distinct in a great number of ways. For one, they are not the merged forms of amoebic lifeforms, but rather similar to multicellular life in the sense that they reproduce, gestate and develop complexity in similar fashions.

The basic structure of the Vitaegel is a gelatinous substance, fluids contained in networks of complex chemical chains. Suspended within this gel are organelles of varying size and complexity, by default distributed throughout the organism. This includes stores of genetic information. The entire structure is often enclosed by a tough outer membrane and threaded with a complex immune system. They vary in shape more than humans vary in skin tone, eye color and hair color combinations, leading to their alternative name: Polymorphs. This is also due to their ability to redistribute organelle distribution and directly command very baseline levels of their biochemistry.

Evolutionarily, the planet Vitaegel are native to is unusual. Multicellular life seems to have been repeatedly out-competed by more bizarre alternatives. In fact its unclear if Vitaegel are even a distinct species when compared to the flora and fauna of their homeworld.

The "brains" of Vitaegel are organelle complexes that utilize altered genetic material as a medium to store information. These complexes consist of several layers, the outer sphere being simply to isolate the sensitive structures, the middle membranes are responsible for much of the complex activity around producing, manipulating and packaging and ultimately transmitting the gene-synapses, and the central structure itself. This central structure consists of the aforementioned former genetic material.

Communication is achieved via packaging these "genetic" structures in a packet of sorts, redundantly so as to avoid the potential for miscommunication, and then physically exchanging it with another. In some sense, talking is mating to the Vitaegel, as they can use the communicated information to make alterations to their biochemistry.

Vitaegel were actually contacted prior to achieving spaceflight, due to a series of mishaps leading to the realization that their planet was inhabited. They have rapidly become a fixture of much of the local galactic community, their adaptability and reproductive rate is beyond compare after all.

Perception of Humans: Weirdly inflexible clonal colonies of extraordinarily specialized individual lifeforms. Thoughts do not arise normally, instead arising from the simple communication of billions of individual lifeforms. They communicate abstractly, using wave-patterns of various kinds to make information known. The concepts communicated are simple, but act as "keys" to complex abstract objects. Essentially just another alien. 

Pictured: Intolerably cold conditions for a Lithomorphic lifeform.

5. Lithomorph-48

Deep in the mantle and outer core of terrestrial worlds, it is possible for obscure chemistries to take place. The variety of these that can occur is beyond the ability of any one person to list, but the most relevant are the complex irregular crystalline structures that form in particularly chemically diverse worlds.

These crystals, at the basic level, can perform specific processes. They are naturally occurring machines, powered by local heat gradients, exotic chemical reactions, kinetic energy and electromagnetic phenomena generated by the planetary core. These machines, in many places, have formed dense clusters which eventually achieved homeostasis, and self-replication. Cellular life of sorts. Abiogenesis, in a completely alien environment.

Life has many challenges as it reaches to the stars, if it ever seeks to. It must ensure that its units survive in the hostile environment of space. It must ensure that they can resist the gravitational pull of the celestial body they develop on. It must ensure that they do not perish in the return trip.

Though equally (perhaps more) common than carbon-based life, lithomorphic life has many many more challenges. The heat and pressure requirements for them to survive are extraordinary, the alloys required to maintain such things are exotic even by their own standards. All of this, and they must have the desire to reach for the stars, and some way to get through the tough, cold upper mantle and life-consuming cold of the crust.

Lithomorph-48 won the cosmic lottery in this regard. Their proximity to their star scoured the atmosphere of their planet and rendered its surface molten. The regular solar flares deposited enough materials to maintain the planets mass, even as it might have otherwise very slowly fallen apart under the intense conditions. This contributed to a regular influx of exotic elements deposited at the surface, encouraging experimentation.

Physiologically, it is difficult to describe Lithomorph-48. Their shape might not be too out of place in an oceanic abyss, a meter long "trunk" that branches into multiple "arms" on one end, with a "bell" of sorts for moving through their medium. Their technology is mostly their equivalent of "biotechnology", taking advantage of their naturally evolved chemically flexible "glands" to grow technologies that aid them. These "glands" seem to have originated as a number of individual synthesis zones for the rapid production of important biochemicals that were favored as they slowly underwent a progressive development.

Early Lithomorph-48 space programs involved chemically induced and focused "supervolcanic eruptions" that launched strange ships into the void. These ships were composed of extremely dense and heat-retaining metal alloys and metamaterials, a requirement for them to even consider going to space. These bizarre contraptions (that would resemble a jet-black chrysalis of some monstrous butterfly to a human observer) kept their interiors within acceptable temperature and pressure ranges, though the residing lithomorphs had to enter their "slow" state to do so. Modern ships resemble these older ones, but the material composition is far more exotic, far more efficient and propulsion is achieved via reactionless drives (as is standard).

Settling and terraforming planets is rare in the Flourishing Void. Life-supporting planets are usually observed from afar, or closely in a controlled manner when more exacting science is desired/required. In the rare cases where a planet is settled (usually a lifeless one with surface or sub-surface habitats) then Lithomorph-48 volunteers will often begin to settle its deep interior, working with the surface world in symbiosis.

Perception of Humans: Extremophiles of the highest order, living far beyond where all life should be rendered impossible, composed of strange chemistries that can only operate at all-consuming life-obliterating cold. Not even twice the total length and volume of one of us, but over ten times as diffuse. Their senses turn to the void and they can impossibly percieve other celestial bodies, other stars, without instruments of interpretation. If they entered our habitats, they would collapse into only so much exotic chemistry. They are strange, delicate, diffuse, alien and beautiful, drifting at the edge of possibility.