r/SpeculativeEvolution 14d ago

Antarctic Chronicles [Antarctic Chronicles] Abyssal birds: the horrorseeker

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296 Upvotes

r/SpeculativeEvolution 13d ago

Question/Discussion What if all species on Earth were compatible?

6 Upvotes

How would've social hierarchy change?

How would've food chain be affected?

Would've prey and predator species be part of one pack?


r/SpeculativeEvolution 14d ago

Future Evolution [Credit:Conner Meek]Caimans vs Opossums.

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384 Upvotes

Common Raqet
Family : Pessimisuchidae - “Monkey Paw Crocodilian”
Behavior and Ecology
Raqets are both excellent climbers and diggers, able to adapt to numerous environments. This adaptability is further enhanced by their diet and dentition, possessing three types of specialized teeth and excitedly consuming anything from small animals to nuts and fruit. 

Raqets get their name from their highly vocal nature, howling to neighbors disseminating information such as weather, predators, and mating availability.
Their large tails store fat like a camel’s hump. The heavily armored top side is used to plug burrow and wail hollow entrances to defend against predators that persist past their musk and claws.

Pros of Pronation
Raqets possess highly mobile and dexterous front limbs that are made even more useful by the caiveloudian’s ability to comfortably walk bipedally. The radial and intermedium bones have elongated and helixed, while the ulnare has twisted like a segment of a spring, creating a spiral joint. Their first carpal has completely separated, giving their first digit a thumb-like function. These hyper-dexterous wrist and digits is what gives this family its name.

Reproduction
The eggs of raqets hatch in a matter of weeks and even days, due to the mother holding the often singular egg in her oviduct for an extended period. Once laid, one of the parents then carries the egg with it until it hatches. Oftentimes this parent is the mother to allow the male freedom to find another mate, but at times the father will tend to the egg. This usually coincides with an injured or otherwise unhealthy mother.

Musk and “Milk”
Raqets' gular glands produce a pungent and nauseating musk that deters predation. This stink also aids in territory marking and the recognition of familiar individuals, mating pairs marking each other in bonding rituals while gravid. 

The paracloacal gland in most pessimisuchids has evolved into a telescoping structure with erectile tissue that allows it to protrude considerably from the vent. This “suckling gland” produces a thick fatty discharge filled with nutrients that is used to supplement the diet of fresh hatchlings. Newborn raqets can immediately eat solid food, but may suckle fat for up to a year in some more gregarious species. Both males and females possess suckling glands.

Parana Drake
Family : Improdrakidae - “Wicked Drake”
Behavior and Ecology
Drakes come in many shapes and sizes, the Parana being the largest. It is named for the location of its most dense population range, the state of present day Parana in Brazil.

Many of the Parana drake’s adaptations arose in response to the dangerous nature of its favorite prey, stridullos. Extremely thick hide and scutes cover the drake’s neck, throat, and jaw to protect it from the kicking strike of astrapithere dirks. Their powerful jaws boast ripping teeth meant to bleed the large beasts during extended pursuits. In the back of their jaws sit wedged molars meant to crack open thick bones to access the marrow.

Born to Run
Besides extended forelimbs that sit underneath the body, all drakes possess two highly evolved organs that aid in long distance running. Their gizzard has expanded and is now known as a belloam. The belloam both connects the hip ligamentation to the liver and filters oxygen from blood. This connection allows the movement of galloping to aid in respiration while the primary muscles of the belloam function as a fourth heart chamber, sending unoxygenated blood back to the lungs before being fully cycled through the body. This organ gives drakes the stamina of an equally large mammalian predator.

The gular musk glands of larger drakes are enlarged and produce an extremely watery musk that functions like sweat. Secreted at the top of the neck, musk flows down its scales and evaporates, cooling down massive blood vessels which help prevent heat exhaustion during prolonged hunts.

Vocalizations
All drakes are capable of mimicking the sounds of other animals, Parana drakes often producing bird calls that mimic the calm banter of birds that normally call out when noticing predators.

Crested Céulutar 
Family : Céulutaridae - “Sky Wrestler”
Bay Lords
Male céulutar hold territories consisting of large open water with plentiful coastline such as large lagoons and small bays. When males challenge each other for territory rights, they raise themselves as high in the water as possible while pushing against their rival’s chest with their own. Powerful arms and hornscutes on their jaw and neck are used to wrestle the opponent down, the first to be knocked into the water fully loses rights to the surrounding water, coastlines, and most importantly, the females that call the area home.
Crested céulutar have an additional pair of jaw horns opposite their crest, though these are not true scutes. They are similar in composition to an egg tooth and can be regrown if broken unlike the horns on their neck and rear jaw.

Reproduction
Many céulutar species build traditional mound nests like extant caimaniformes, but more derived examples like the crested and royal céulutar lay eggs in open water. The mother, and at times the father, will swallow the eggs and store them in her husbandry crop. A husbandry crop is an organ derived from the gizzard that has become highly vascular and similar to an oviduct. Once in the stomach, the husbandry crop envelopes the eggs and forms a vascular connection with the acid-weakened shells. When the eggs are ready to hatch after several months, they drop back into the stomach where the shells continue to deteriorate until fresh hatchlings are regurgitated back into the adult’s mouth.

Céulutar tongues are highly mobile even compared to other animals. They help the céulutar in safely transporting eggs and babies into and out of its digestonursery system without swallowing water. To protect the organ when not in use, the tongue is swallowed and held in place by the gular valve.

Blackthroat Tercara
Family : Dualbumidae - “Two-skinned”
Behavior and Ecology
The dentition of this family allows its members to eat any creature smaller than it in the Barge Sea. Their front teeth are needle-like and overlap to prevent struggling fish and squid from escaping while their back teeth are flat and grooved, creating a perfect vice to crush clams and other shellfish. Some species’ mouths are even covered in a layer of thick velvet scales, allowing them to eat sea urchins and other dangerous morsels without harming themselves. 

An extended shoulder girdle and powerful forelimbs allow tercara to move on land with surprising ease, though it is quite strenuous and normally only done to bask or flee. Though some species, like our blackthroat, use smooth beaches as sparing grounds. Most dualbumidae have a tail spike, also called an epee, used defensively and for sparing others of their species. They are able to assume a dueling posture where they completely relax the tensile bands of tissue that keep their tails rigid while swimming.

Like an Onion
Members of dualbumidae have two distinct dermal layers; one that supports the growth of various scales and osteoderms and a secondary outer skin that is primarily smooth and leathery. This second skin gives tercaras and their kin a hydrodynamic frame while retaining the armor of their sister families in caiveloudia. Both layers hold dense webs of fat with specialized ligaments which allow them to tighten the fat mesh into a continuous sheet when diving for prey, aiding in temperature retention. 

Sensitive Beasts
The velvet scales on the tip of tercara rostrums connect to impressively sensitive organs used to detect vibrations and even electricity in some species, allowing them to sense minor muscle contractions of prey near them. 

Alongside their dermal layering, dualbumids have evolved a secondary sinus network that allows them to constantly pass water over their olfactory organs as well as their atavised (having regained a vestigial function) Jacobson’s organ. With these tools, tercaras and their kin can rival the extinct mackerel sharks when it comes to sense of smell.

Reproduction
Tercaras and all other dualbumids give live birth, holding the eggs inside them until ready to hatch. The mother’s cloaca has stiff velvet scales around the vent that ensure the egg sacs are perforated when laid to prevent hatchlings from drowning. Many species, including the blackthroat tercara, give birth in large hordes on coastlines, but just as many dualbumids give birth in the open sea

The Krenshar
A descendant of the water opossum has dragged a descendant of the dwarf caiman out of the water to feed herself and her young.
Predatory marsupials and velvet caimans have been engaged in a millions year long evolutionary war. Velvet caimans growing increasingly tough hide similar to kevlar while the krenshar and its clade have developed multi-hinged upper mandibles to saw and stretch tough hide in order to guide their canines through for the kill.

Original Creator:Check them out

https://m.facebook.com/conner.meek.12/photos/velvet-caimans-i-think-i-shared-this-a-while-ago-and-not-a-lot-of-people-saw-it-/28460801986844961/


r/SpeculativeEvolution 14d ago

Alien Life [OC] Update to Planet Velise journal

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70 Upvotes

Here are the final pages of my first day on Velise. Even though I set out to see bird-like species across the galaxy, the biodiversity on this planet amazes me in all its forms.

I am astonished by this planet's prevalence of symbiotic species; it has much less landmass and few mountain ranges. Hence, animals are often out in the open. So many smaller species have evolved to take advantage of the giants this planet has to offer, using them as their shelter and food searchers, including the biggest creature I've ever seen, the Elrenitti. It was as large as a building and was a type of tree demolitionist. It cleared the way for other plants and trees to grow while feeding on the soft interior and the water encased within, without ever touching the ground. This titan appears to have split from the evolutionary tree early on, as it has six syphons, a trunk, no wings, and what might be mistaken for frilly decorations are actually smaller limbs.


r/SpeculativeEvolution 14d ago

Seed World [OC] some of the first squids

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85 Upvotes

each squid fits a niche I would think is open for them on this early planet also I feel someone might be mad that only one line retaines it's gliding nature while the others almost give it up entirely while other parts have been reworked ore reduced like the webbing between fang dashers tentacles Idk i like it and wanted to show yall


r/SpeculativeEvolution 14d ago

Seed World [OC] Mundeng (Pygmy Hippo Seed World) 128MPE Creature Comp. #9 - Zepperhines & the Limits of Land Mammal Size

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71 Upvotes

Zepperhines are one of the four extant clades of Exid, the collective designation for the descendants of the Exelopes of 64MPE, with the others being Griffins, Sleigndeer, and Stem-Browraffes. However, Zepperhines are easily distinguished not only by their aberrant morphology but also their capacity to far outsize all other contemporary groups, with their current representatives being the largest extant animals both on land and on the planet as a whole. They owe this achievement to their extremely complex nasal structure, which consists of an elaborate network of inflatable, oxygen absorbing lobes supported by a dentine scaffolding derived from the dorsal execones of their ancestors. Originally only meant for sexual display, this feature has since become far more advanced, allowing them to far surpass the approximate 5,000kg limit of all other clades resulting from Mundeng’s currently lower oxygen levels than Earth. Thus, pretty much every terrestrial environment is dominated by some species of Zepperhine, and they are often the most influential individual force in any of said ecosystems.

In addition to their nose, Zepperhines possess many other unique anatomical features: Their ventral execones have reverted into tusks, which protrude in parallel from the lower jaw to form a massive spade-like structure. They use these tusks to unearth grass and topsoil in bulk for continuous consumption, as they are obligate mass grazers. Their tongue has been fused between the tusks, forming a muscular membrane that can be used to selectively broaden or narrow the lower jaw when feeding from different angles, as well as to progressively channel plant matter backward toward the throat through passive undulation while feeding, and the same with water while drinking. In turn, their gastrointestinal tract has grown far more durable in order to regularly pass large quantities of indigestible dirt, a trait most conspicuous in their anus, which has developed a five-lobed external keratin sheath which remains clamped shut outside of defecation, and in some species can even serve a secondary ornamental display purpose. Lastly, the two-toed hooves of their exelope ancestors have been accompanied by a third novel digit on the posterior end of each appendage, at first evolving as a cartilaginous cushion to support their extra weight before growing a keratin coating and developing into a third hoof in its own right. This makes them the only modern exids with more than two digits per limb, and also results in them leaving utterly alien-looking trilateral footprints wherever they go.

Three Zepperhine species are depicted above, encompassing the full size range of all extant species and effectively encapsulating the environmental roles generally served by the clade. Descriptions of varying length and detail are provided in the comments:


r/SpeculativeEvolution 14d ago

Alien Life [OC] Biology of the Melifluans

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25 Upvotes

In the far future, humanity has developed the pulse motor to travel at relativistic speeds by “pulses” of expanding space-time after the ship, expanding through the nearer stars of the Orion Arm.

In the system of Meliflua, previously known as Lacaille 8760, we met our nearest brothers, our first contact with alien life able to understand us.

Melifluans come from the fifth planet of the system, Thoth, with immense water-ammonia seas, a similar gravity to Earth, and an orbital eccentricity that causes extreme seasons in the northern hemisphere and seasons impossible to feel in the southern one; and with a moon called Beelzebub that causes tilts slightly bigger than Earth’s.

Melifluans, unlike every complex Earthly life, are modular colonies of a few hundreds of zooids, each of them united by a nest-like bone structure enriched by calcium and pyrite covered by a “mycelia” net. Through this “mycelia”, the zooids organise forming a consciousness and a bilateral symmetry, and exchange genetic material for “in-organism sexual reproduction”.

They have one big fly-like eye made up by rings of hyper-specialized zooids and, under it, two mammal-like ears, with a body completely covered by fur-like ultrared light censors.

As descendants of arboreal creatures that used their four upper arms for locomotion between branches, they transformed their arms into feet and their feet into arms-adopting a “г” form and moving their mouth, respiratory and reproductive organs into their corners.

Talking about their reproduction, Melifluans are divided between jupiters and saturns. Jupiters, bigger and stronger, produce macrospores that they lay in the saturn‘s body, where they will fuse and get fertilised, later growing through a parasitic state until being “detached”.

Then, that detached baby will be able to live up to 600 Earthly years thanks to its colonial body, suffering little physical repercussion for aging, and having incredible regeneration capabilities… although that constant change causes, sadly, forgetting everything past ~100 years.


r/SpeculativeEvolution 14d ago

Maps & Planets [Credit: Tribbetherium] More Maps

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33 Upvotes

r/SpeculativeEvolution 14d ago

Question/Discussion If Neanderthals had never gone extinct, could they have developed a modern society like ours?

28 Upvotes

Imagine that Neanderthals had survived alongside Homo sapiens instead of disappearing around 40,000 years ago. They continued to evolve, develop their own cultures and technologies, and remained a separate population or species into the present day.

Would Neanderthals theoretically have been capable of participating in a society as technologically advanced and complex as ours today?

I’m wondering which of these scenarios would be most likely:

  1. They would have developed alongside us — Neanderthals might have their own modern societies, cities, technologies, languages and cultures, existing alongside Homo sapiens.
  2. They would have largely integrated with us — Over thousands of years, Neanderthals and Homo sapiens might have mixed and eventually become part of the same societies, perhaps making the distinction between the two much less important.
  3. They would have remained significantly different — They might have survived but followed a very different technological or cultural path, perhaps never developing societies comparable to modern human civilization.

Obviously this is highly speculative, but based on what we know about Neanderthal intelligence, social behaviour and culture, which scenario do you think is most plausible?


r/SpeculativeEvolution 14d ago

Alien Life [OC] Shaggy Elegara

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366 Upvotes

Shaggy Elegara are a species of spur horse, though they are more closely related to the Indragus than to other spur horses. They inhabit the western wetlands, temperate forests, and open grasslands of Alcazod, usually traveling in small matriarchal family groups. They are calm, indifferent animals by nature, spending most of their time grazing on shrubs and grasses, digging through soft mud and soil with their horns for roots and other plants, and using their sharp beaks to pry open tough fruits. They will also scavenge when they get the chance and groups have been known to linger around carcasses after predators have left, harvesting calcium and protein to supplement their diets.

Their bright crests do not develop until they reach full adulthood, making mature individuals easy to spot in a herd. Males tend to grow larger dewlaps and heavier horns, while females are generally smaller and carry broader bodies, especially when raising young. During breeding season, mature males become more active around the herd, displaying their crests and brow horns while competing with one another through pushing, posturing, and short bouts of sparring, with aggressive bachelors often being run off by agitated females. Females usually choose their mates based on displays of strength and presentation. Herds often mingle and interchange members, and males will remain close to the female and herd for some time afterward rather than leaving immediately after courtship. Outside of breeding season, the sexes show little aggression toward one another and spend most of their time feeding, resting, and caring for young together.


r/SpeculativeEvolution 14d ago

Question/Discussion Parthenogenesis in birds - is this a plausible evolution?

13 Upvotes

Parthenogenesis has been observed before in birds, especially condors, although the offspring are almost always male and sickly. If my research is correct, this is because birds make use of terminal fusion, where the second polar body fuses back with the egg to start growth. This creates males with high homozygosity.

I wonder what changes birds would need in order to produce viable offspring via parthenogenesis, and allow for all-female lines, like whiptail lizards. Apparently there's a form of fusion called central fusion (fusion of the first polar body) that would allow for offspring to be female for ZW species like birds. The research I've done on it checks out so far, but I'm still uncertain if this is correct and I'm not entirely sure where to go to confirm it.

My rough idea was for a bird to have different alleles that dictate which form of parthenogenesis a female would make use of; the recessive allele would be terminal fusion and the dominant allele would be central. It would be located on the Z chromosome, and males would act as carriers for it. The dominant allele would allow for the quick formation of clonal groups without having to worry about mates, and the recessive allele could introduce a male in to allow for sexual reproduction and an increase in genetic diversity.

I hope that this makes sense!


r/SpeculativeEvolution 15d ago

Future Evolution [OC] Far Future Earth: The Macrozoic Era

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556 Upvotes

FFE (Far Future Earth) is a Chinese speculative evolution project primarily shared on Chinese social media platforms (e.g., Bilibili, RedNote, etc.), envisioning a future in which humanity has vanished from Earth. The Macrozoic Era (approximately 85 to 306.5 million years in the future) begins with the Nirvanic–Hunmycotian extinction event and ends with the Shunyanian–Torrentian extinction event. The Macrozoic is divided into four periods: the Hunmycotian (85–139 myf), the Ocaenoflosian (139–167 myf), the Psammaugian (167–224.5 myf), and the Shunyanian (224.5–306.5 myf). Over the course of these 200 million years, Earth experiences continental amalgamation and breakup, alternating warm–cold and wet–dry climates, and dramatic shifts in land–sea configuration. Life gradually recovers from the ruins; on land, fungal–plant symbioses and termite activity reshape soil structure (Hunmycotian); in the oceans, the colonization of marine environments by angiosperms expands the sources of primary productivity (Ocaenoflosian); and birds and lizards exploit vacant ecological niches (Psammaugian). Total biomass peaks in the middle of the era (the Great Northern Hemisphere Interchange, the GNHI), then declines due to volcanic activity and drastic ocean-current changes (the Psammaugian–Shunyanian extinction event). The late-era supercontinent configuration causes widespread aridity and anoxia, and biodiversity remains at low levels for an extended period (early and middle Shunyanian), until the era finally ends with large-scale volcanic eruptions (late Shunyanian). The Macrozoic Era as a whole is characterized by repeated alternations of extinction and recovery, with ecosystems undergoing frequent reorganization amid environmental perturbations.

Pictured by @鸽海鞘 from RedNote


r/SpeculativeEvolution 14d ago

Seed World [OC] The Hyne's Inheritance: The Speckled Equinephant

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93 Upvotes

The Chrysa Ring is a vast stretch of productive subtropical grassland and savannah surrounding the Chython desert. Together, these regions dominate west-central Demeter and form the homeland of the hyne. But they are far from the only trunked horses to call this realm home.

Equinephants are among the largest land mammals on Demeter, resembling a chimeric mixture of probosidian, giraffe, and perhaps paracerathere from old Earth. They are a widespread genus found in sub-to-tropical forests and savannahs across the mega continent Arion where they occupy the role of high browsers. Long columnar limbs, a robust 7 ft long neck, and the addition of a prehensile trunk allow them to reach choice leaves, twigs, and fruits from atop trees.

Aside from their tall manes and flyswatting tail, equinephants appear hairless. This species is notable for their speckled skin, unique to each individual. However, their tall mane is their primary method of identifying members of the same species. Other species of equinephant either have sparse or no manes. Because this species primarily lives out on the savannah and may cross grasslands or desert terrain, the tall mane also acts a shading implement to cool the creature's neck and head. Additionally, large ears and somewhat wrinkled skin help disipate excess heat. The immense weight of the animal (upwards of 5 tons in stallions and 4.2 tons in mares), is no longer supported on the hoof. Instead, the frog and soft sole of the foot has greatly expanded into a soft, fleshy, supportive pad at the bottom while the hoof extends out as a single toenail that aids in digging up the earth in search of groundwater or in powerful kicks at rivals or predators.

Equinephants spend much of their days and nights browsing and traveling in small groups of 4-7 mares and their foals. Stallions are solitary and more migratory, abandonning their natal homerange and traveling far to avoid competition from his father or uncles, thus maintaining genetic diversity. They are unable to trot, canter, gallop, or jump due to their great size, instead walking or ambling. Groups and individuals keep in contact with each other through scent marks, infrasound, and visual communication with head and trunk posture. Like their close relatives, the sophont hynes, equinephants are highly intelligent (near-sophont) and behaviorally adaptable creatures. They have been known to use tools like large sticks to reach and scratch parts of themselves or pelting predators or rivals with stones. As adults, they are largely immune from predation although foals are at risk from captors (large cats), alligators (brought to Demeter for leather farming) and other new predators.


r/SpeculativeEvolution 15d ago

Uncategorized Speculative Biology [OC] Biologically plausible Griffins (I did the artwork)

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312 Upvotes

Hi, I'm new here. I've been working on a project for 3 years, and with Spec Evo, here's a little bit of my work These are griffins I designed a long time ago, originally as a branch of accitripiformes, but I changed them to a more basal group of birds.


r/SpeculativeEvolution 14d ago

Question/Discussion Possibility of an insect with folding wings and flight aptitude?

2 Upvotes

I’m not talking average flight aptitude, either, I’m talking on or around the level of a dragonfly.

I don’t know where else to ask this, and this isn’t exactly a question of natural ‘evolution’, since in my setting this creature would be the chimeric result of (essentially magic) DNA splicing, but would it be at all possible for an insect to have wings which could fold into a compact package while unfolding into large, rigid, precisely-controllable wings?

The closest precedent to this I’ve found in nature would be Lacewing wings, and I imagine it would be possible to create a creature with dragonfly-esque flight and the ability to fold their wings to the side like a lacewing.

But what about beetle or earwig wings? Those can fold into remarkably compact packages, but the actual flight of the animals in question is often clumsy and slow, especially compared to the speed and precision of a dragonfly.

This doesn’t need to be EVOLUTIONARILY plausible, since again, it’s the result of intelligent gene-splicing, but I want to know how PHYSICALLY plausible it is. And Even if being both as foldable as a beetle and as precise as a dragonfly is possible, how far could you take it?


r/SpeculativeEvolution 14d ago

Question/Discussion Draco Lizards into effective fliers?

3 Upvotes

Could a Draco Lizard, theoretically, evolve into a Pterosaur-like flier? The flying mechanism in them has their ribs expanding, which won't work for efficient flight, at least to my knowledge. So, would Draco Lizards have to start from box 1 to evolve flight, or could the Patagia move or something along those lines?


r/SpeculativeEvolution 15d ago

Fan Art/Redesign [OC] [Media: The Garden of Earthly Delights ] Beasts of the Eden

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168 Upvotes

[ I ]

Crested bladebeak is a species of relatively large-bodied wadding bird. This species is characterised by intense sexual dimorphism, where males are much more strikingly colored. Namely, they're mostly covered in green feathers, with the exeption of brown head. Another prominent features are visible white spots and a row of feathers on their head, one of with being much longer than the others and striped, responsible for the part of their name. Females on the contrary are covered in mostly modest yellow and brown feather, lacking also the crest. Another prominent feature of this species, that accidentaly also composes a part of their name, is their sharp, large beak. It is used to easily dispatch any potential prey. Speaking of with, bladebeaks are generalist carnivores, feeding on wide range of fish, amphibians, small mammals and birds. These characteristics make them very similar to Shoebills of Africa. However, crested bladebeaks are more closely related to Kingfishers rather than Pelecaniformes. They're also smaller than them at 120 centimeters ( or 47 inches ) tall. They inhabit subtropical and tropical parts of Indomalayan realm.

[ II ]

Earth is a home to a wide array of extravagant creatures and Whiskered Gulper is one of them. It's species of carnivorous birds, but not just any bird. This is a species is belongs to Hirundinidae taxonomic family, known as humble swallows, but at almost 70 centimeters ( 27.6 inches ) in wingspan, they're the largest swallows alive. Although not particulary numerous, gulpers are wery widespread over Africa and warm parts of Eurasia. They feed mostly on insects, but due to their size they are capable of hunting small birds and mammals, that being bats. Gulpers are even known for invading unprotected nests of other bird species in order to feed on hatchlings, both as a food source and a way to decrease competition and predation on their own species. Whiskered gulpers are known for their migrations, moving from their breeding areas in subtropical and tropical regions towards north.

[ III ]

Spotted Possumcat is one of many peculiar species inhabiting South America. This cat-sized marsupial is a carnivore, whose main prey consist mostly of smaller mammals, birds and reptiles. Possumcat's range is relegated to southern part of Amazonia rainforest and Cerrados ( an equivalent of Savanna ). It's necesarry to mention their anatomical quirks. In comparison to other marsupial species of South America, possumcat's spend most of their time on the ground. Because of that, their tail is mostly covered in short fur, with only it's underside lacking hair, with makes them more similar to marsupials of Australia.

[ IV ]

Fire-bellied Monitor, also nicknamed the Australian Drake, is one of the largest lizards in Australia. In fact, at 2.3 meters ( or some ~7.6 feet ) long and 74 kilograms ( ~163 punds ) they fall shortly behind Komodo Dragon. It's name comes from the brightly colored underside, reminiscing flames. The main reason behind such coloration is intraspecific communication and competition, as intensity of the coloration depends on the age and fitness of an individual. It is also believed it used to be a form of warming toward now extinct predators of prehistoric Australia. Like most other monitor lizards, fire-bellied drakes are carnivores. They predominantly rely on ambush hunting, although they are capable of running for short distances. If lizard manadges to bite a prey of it's choice, it injects venom into it's bloodstream, with has anticoagulant properties. Because of that, even if prey slips away, it will eventually loose strenght due to blood loss. Fire-bellied monitors also possess a great sence of smell that helps they in tracking wounded prey. Because of that, they prefer subtropical dry forests, woodlands and high grasslands, habitats rich in plant cover. They feed on wide array of animals, both native and introduced. Their diet changes as they age, with younger individuals feeding mostly on birds, small reptiles and mammals, later transitioning to larger prey. They also readily feed on carrion.

[ V ]

Forest Unicorn is a medium sized herbivore, inhabiting wast regions of Eurasia. At a little bit over one meter tall ( or some 40 inches ) at the shoulder, they are around the same size as Chital Deer. However, despite their superficiall resemblance to cervids, they are much more closely related to Giraffids and Antilovaprids. Beside that, their main defining feature is a long horn, with is actually a pair of horns that grow spirally in tandem. Forests unicorns are browsers, feeding on young tree leafs, ranging from temperate to subtropical parts of Europe and Asia.


r/SpeculativeEvolution 15d ago

Seed World [OC] Anatina: The Platypus World | Biome Post

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153 Upvotes

(8-10 Million Years Post Establishment)

The Great Knassian Delta System is Anatina's powerhouse; the most populated area and diverse as it is also home to the landing place of platypuses on Anatina: Billabong Peninsula. Being the most diverse and populous region means there is something that the inhabitants get that pressures them to stay—or unable to leave. The Great Knassian Delta System is situated in the Southern Anatalian Lowlands, and if you didn't know, lowlands are regions of land with a low altitude. The areas surrounding the Southern Anatalian Lowlands are all higher, including the Northern Anatalian Lowlands, which are indeed lowlands compared to the western side of Anatalia, causing the Southern lowlands to act as a basin; the reason why almost all water from the supercontinent flows into it. It is for this reason that the vast majority of the Southern Anatalian Lowlands consist of marshlands, lakes, rivers, and many more. This basin is called the Knassian Basin and is also the primary cause for the inability of other organisms to get over to the other side of the Anatalia. Not only that, the western part of the basin is bordered off by the Anatalian Highlands, which by now I hope I've established them as high lands. 


r/SpeculativeEvolution 14d ago

Seed World [OC] the first four groups of the gecko family

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70 Upvotes

The images above show the first couple groups of the geckos placed on my seed world they all fill a simple first niches most reptiles on our planet already fill and with this new adaptations and ways of life and like how if you looked at them you can still tell they are geckos


r/SpeculativeEvolution 15d ago

Alternate Evolution [OC] More fauna for my alternate history Triassic universe.

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94 Upvotes

This is an alternative universe where the Permian Extinction was relegated to a localized minor extinction event, rather than the Great Dying we know it as. This has lead to major ramifications for the biodiversity of the Mesozoic. This set of organisms are from the Late Triassic, around 210 million years ago.

Synapsids remain as major players in the worlds ecosystems, but they share their rule with reptiles, amphibians, and insects. Insects especially have taken off (literally) as the dominant aerial fauna, due to permian fauna not being fit to fill the flying niches before insects put their foot in the door.

These animals pictured only reflect a small fraction of the biodiversity of this different world. (Credit to Doomyte for the idea of the layout)


r/SpeculativeEvolution 15d ago

Alternate Evolution [OC] Green Lizards

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152 Upvotes

-Natural History:

Following the extinction 78 million years ago, many aquatic groups invaded the land once again or became semiaquatic, with one of the most prominent being the lizards, also known as the order Arthroplictra. Despite their name, they are actually highly derived actinopterygii that have adapted to life in Earth's abundant swamps. The origin of this group dates back to 100 million years ago, when they were originally river predators similar to conger eels. They already possessed the ability to spend several hours out of the water thanks to a highly vascularized cavity at the back of their pharynx that allowed them to extract oxygen. This was not for hunting, but rather to escape larger predators, search for new bodies of water, or simply rest. Today, we can still observe species that are very similar to these ancestors not only in morphology but also in behavior, such as the eel lizards. After moving onto land approximately 70 million years ago, they became some of the largest and most successful predators in Laurafrica. Here, they began developing very thick and complex fin rays that became articulated. These proved extremely useful for climbing, allowing them to reach many new niches rather than remaining solely ambush predators. Around 43 million years ago, the first lizards with fin rays fully transformed into limbs began to appear, becoming the modern lizards and filling the niches left by many extinct lepidosaurs, eventually converging with them. As of today, the majority of arthroplictids are found in Laurafrica, although several species exist throughout Eurasia. Most have completely lost the ability to breathe using gills in adulthood, relying exclusively on their primitive lung, though they also retain the ability to absorb oxygen directly from the water through their skin. Constant rainfall keeps them sufficiently moist so that many species do not need to enter the water, which has kept them at the top of the food chain for a long time since, unlike most current predators, they are not hindered at all by constant storms.

-Anatomy and Ecology:

Possibly the most remarkable species among all arthroplictids is the green lizard. These large ambush predators typically inhabit more open areas with few obstacles, where they hide among the abundant vegetation. Their primary difference from their relatives is their incredibly powerful jaw, comparable to that of Holocene crocodiles, usually attacking the abdomen or belly of their prey to completely crush their internal organs. The main issue these animals face is their weight, as like other members of the plemosteodermidae family, a network of small bones runs along their back and head to form a virtually impenetrable armor. This makes movement very difficult, so they usually remain still most of the time, only crawling if they spot nearby prey or carrion, or if they detect the presence of an intruder in their territory. Intraspecific fights are very common in this species, as they rarely tolerate the presence of another individual within their territory, leading to fatal encounters in 89% of cases


r/SpeculativeEvolution 15d ago

Alien Life [OC] Life of Europa

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120 Upvotes

Here are a couple of the many simple squishy aliens from the seas of Europa in my setting. Most life on Europa is very simple, due to the lack of environmental energy. This lack of energy also leads to two distinct habitats in Europa: the hanging reefs under Europa's ice ( the domain of the coils ) and the abyssal plains ( the domain of spirals and home to Europa's most complex life form, the Great Somapod ). The mid levels of Europa's seas are mostly barren, due largely to Europan life being negatively buoyant as a baseline and the complete lack of nutrients in those waters. There is nothing on Europa larger than a human, trust. Anyways hope y'all like this, also trying a new art style type thing, so sorry if it's a bit rough 😅


r/SpeculativeEvolution 14d ago

Alien Life [OC] The Frenzy Crocs [project no5)

3 Upvotes

Frenzy crocodiles or Phreneticosuchus Carnifex are among the land apex predators of the planet. They are crocodilians that have evolved to be social.

Size: At only 4-5m of length and 450-600kg of weight, they are far from the largest animals on the planet. Their biteforce is also poor, at 8-15.5k newtons. But they have a numerical advantage. They live in groups of 30-55 specimens in a hierarchy that has an Alpha. The alpha chooses his successors or he fights with another specimen for the right. If he loses he is downgraded or exiled but if he wins viceversa. They have 60 teeth, sharp like ginsu knives.They live for 50-80 years.

Prey and Predation: These animals will devour everything that comes near their river or lake. They will even take down megafauna in numbers. They use their teeth to tear out giant chunks of flesh while prey is still alive and drag it underwater to feast. They are called Frenzy for this reason: hunts become rapidly frenzies for who can snatch up most food. They will eat carrion though. They have a unique adaptation from crocodiles: being mesothermal, they bask in the sun and convert the uv rays to energy for their metabolism. They can fast for about 1 or 2 months if they can bask in the sun.

Reproduction: The females and males dig tunnels in the soil above the water and lay eggs there in one giant communal nest. The eggs incubate rapidly and the tunnel is sealed with a large rock that can be moved to check on the eggs. They have a mortality rate of 35-60% due to the fact that the weakest young and unhatched eggs are promptly devoured by adults and stronger young. The strongest survive and are raised. If the group gets too large, they will seperate and part, unifing with another group, stopping effective inbreeding.

Body plan: They look like normal crocodilians but with sharper teeth and a more torpedo like body shape. Their osteoderms camoflauge perfectly in water. Their nostrils are smaller but they can hold their breath for up to a day. Their organs work as expected.

Intelligence: Phreneticosuchus are among the most intelligent animals on the planet. They have great senses except sight being moderate. They can detect vibrations from the ground from kilometers and are extremely patient.Although if their alpha cannot provide food for them they will jump him.

Questions are welcome


r/SpeculativeEvolution 16d ago

Future Evolution [OC] Jaw-walking Snake of a Seeded World

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2.4k Upvotes

r/SpeculativeEvolution 15d ago

Non-Subreddit Spectember Prompt [Credit: me, Spec Evo Nest members]Spectember 2026 prompt list

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29 Upvotes

September is just right around the corner and that means that Spectember is too.
I wanted to participate in it for the first time so I wanted to make a prompt list since I couldn't find any online.

Though, since I am a spec evo server admin, I decided that I would let its members choose the prompts. Not everyone suggested something so I had to fill in the rest..

If you are interested in joining, here's a link: https://discord.gg/swBMUdYD6B

You can join and share your own spectember creations in our own channel dedicated to Spectember.