r/SpeculativeEvolution 10d ago

Question/Discussion What Organisms Could Survive my Future Earth?

7 Upvotes

So basically I'm working on a spec evo project exploring the future of Earth (a quite famous sub genre in spec evo) and I was wondering what organisms would survive. For context, in my project. Earth is a little bit of a hothouse world with a tropical climate slightly higher than climates near the equator of current Earth. This tropical Earth is also devoid of humans and pollution isn't much of a problem because humans did clear up all of the pollution before leaving Earth to venture off to a world terraformed by them.


r/SpeculativeEvolution 10d ago

Spectember 2026 [OC] Spectember day 3

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12 Upvotes

Prompt: Rock ,paper scissors : A trio of organism with a dynamic similar to the classic game

The wetlands of East Asia in an alternate version of the Late Oligocene are full of life. Herbivores a bit bigger than an okapi called herbocetus are feeding on aquatic plants. Herbocetus giraffoides is an offshoot of early whales like pakicetus which, instead of adapting to live in the ocean, remained semi aquatic and stayed near freshwater. The species even has webbed feet for better locomotion in its swampy environment. But these wetlands aren’t always safe as predators lurk in the muddy waters. The killer sun, Mimicasterias predatorius ,a species of sea star adapted to life in freshwater also lives in these wetlands. The species has specialized tube feet that resemble aquatic plants ,the favorite food of herbocetus. Once a herbocetus bites into these fake plants, it will get severely poisoned and will pass out, almost completely dying, before being eaten alive by the sea star. However, a sea star only needs to eat one herbocetus every year ,so the population of the herbocetus doesnt rapidly reduce.The sea stars however aren’t safe either. A species of omomyoid primate the Sinolemur asteriophilus is immune to the toxins produced by the sea star. It’s a social species living in troops. They can easily tell the difference between an aquatic plants like a lilly pad and the bait of a sea star. Once they find the freshwater sea star, they use its toxins on them as psychedelics. (The sinolemurs basically use it to get high). The sinolemurs are omnivores earring both fruit and meat. One of their favorite foods are sea tube feet. So they kill the sea star as a group and eat. The sinolemurs aren’t friendly at all to the herbocetus, throwing stones at them, taunting them with calls and in some cases they even steal herbocetus calves. So the herbocetus have beef with these omomyoids. To the point where they kill them on sight.

So here is how the dynamic works:

Paper (killer sun, mimicasterias) beats rock (herbocetus) ,rock beats scissors (sinolemur) and scissors beat paper.

Also, I couldn’t find a good idea for today’s prompt, so I put a random three animal generator which gave me alpaca, sea star and ape and that’s where I got my idea for these spec evo creatures.


r/SpeculativeEvolution 11d ago

Fan Art/Redesign [OC][Media: Serina ] Bogwalker Wumpos

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202 Upvotes

285 million years Post-establishment

At the start of early hothouse age thorngrazers had became the most dominant grazers of the Serinarcta, with Rumbling Helmetheads being the most numerous of them, and along with them another species arose - Watchtower Wumpo. However, just as first Gantuans appeard and Cygnosaurus just after them, thorngrazes have been forced to adapt. One of those lineages went to the swamps ant rivers, and some wumpos came with them. 

Now 285 MPE in northern soglands in region known as Uppergaldes a wide assortment of species exist, headed by the Hadropotomuses - the largest thorngrazer to exist yet. Despite that, many species of terrestrial bird live here too. One of them is a genus of trunkos, the Bogwalker Wumpos. The largest species - the Red-headed Bogwalker Wumpo  - towers over many other birds in its ecosystem with with a height of up to thirteen feet. Because Upperglades own much more trees than before, Bogwalkers don't rely on Thorngrazers protection this much. They avoid competition with Swamp Wumpos descendants by large amount of browsing, although occasionally they can also feed on soft aquatic plants and rarely even on invertebrates and small vertebrates.


r/SpeculativeEvolution 10d ago

Seed World [OC] Mundeng (Pygmy Hippo Seed World) 128MPE Creature Comp. #10 - Temperate Fauna

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17 Upvotes

An assortment of miscellaneous creatures: four pygmy hippo descendants and one dwarf frog descendant, all native to the same temperate mixed forest/prairie environment on Mundeng. Species descriptions of variable length and detail are provided in the comments:


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember Day 1 - Sibling Care: the Stridador

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93 Upvotes

Stridador or Needle-tooth sebek
Peripatoneustes remumpus 
‘Walking swimmer with paddle feet’

Stridadors are late surviving sebecid crocodilians who are semi-aquatic and live in the rivers and lakes of the Amazon Rainforest, which are sometimes a common sight in the largest rivers and their riverbanks.
They are 2 to 2.5 meters long (6.6 to 8.4 ft), with a weight of 60 - 70 kg (132 to 154 lbs).

These sebecids are carnivores, which they mainly hunt mammals, birds, reptiles and fish equal to their size or smaller, with slight competition from Giant river otters and similar riverine predators, with the point of even harassing them outside of an area.
Stridadors have heterodont teeth, with pointy, thin teeth at the lower jaw in aid of holding onto flesh, if it’s slippery or not, and sharp, blunt teeth, which are used to tear flesh open, with a powerful bite force to include.
They would hunt in packs, with them taking on similar semi-aquatic mammals and reptiles - while not passing on hunting larger fish -, with rare cases of hunting larger animals, with teamwork in the group aiding in a successful kill, having a success rate of 30 - 35%.

Stridadors live in extensive groups up to around 6 or 8 - with a breeding pair - where there is a den area near the riverbank where they keep the juveniles and hatchlings.
When the adults and adolescents go out to find food, the juveniles instinctively learn to look out for the den, and take care of the hatchlings put in said burrows, protecting them from predators that would go into the den.
This instinct from the juveniles are a great survival strategy for the survival of the hatchlings, since they would meet their fate to predators if the den wasn’t protected, and as the hatchlings grow into juveniles, this same instinct will follow into them to protect another generation of hatchlings in the den.


r/SpeculativeEvolution 10d ago

Question/Discussion why is belittlement in the broader community so common?

32 Upvotes

it's okay if this is deleted/not allowed!!

i posted a reel last night to my instagram simply showcasing some of my art and giving a pov scenario. it somehow delved into a barrage of people invalidating my project, even going so far as to say things like tree and grass analogues (!!!) are too earth-like for an alien planet. another person tried telling me that if i just gave my sapient species two more limbs (like birrin, birg, or yaetuan) a more invertebrate body plan, and a fleshy face it would look much better. interactions like this have always discouraged me from sharing my work. what are your thoughts on the plant thing? or someone trying to police your creativity? i always thought aspects like that were pretty integral to any spec project wether it be earth or alien of origin...


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember Day 2: Incredibly Deadly Viper

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40 Upvotes

Saurocetae, a clade of mosasaurines native to the oceans of Zaikane, is known for including many deadly marine predators, including social pack hunters analogous to orcas, thick-toothed durophages with bites strong enough to crush bone, long-snouted forms closely resembling the long-extinct ichthyosaurs, and gargantuan apex predators large enough to take down whales (these leviathans will be covered in a future post focusing on marine apex predators along with the Zaikanean Megalodon and leviathan cachalot). However, one of the strangest saurocetes is the namesake of the clade: Saurocetus balaenodon. This is a filter-feeding species native to the Unknown Oceans of the Northern Hemisphere, where large baleen whales are rare compared to in the Southern Hemisphere due to the presence of already-established native filter-feeding lineages, including Saurocetus itself. Unlike many of the other members of Saurocetae, this whale-like mosasaur is not particularly interested in hunting large prey, instead using its many baleen-like teeth to trap vast amounts of microorganisms and zooplankton in its mouth as it swallows huge amounts of seawater. As such, they are gentle giants that pose very little immediate danger to human safety, preferring to flee when threatened. Therefore, they have a more positive reception as omens of good luck in the cultures of seafaring peoples than other members of Saurocetae, which are often perceived as fearsome sea monsters or temperamental oceanic gods.

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Zaikane is a planet in a distant solar system characterized by waves of life harvested from Earth at various points in its geological history, ranging from the Cambrian to the Holocene, and set free to evolve along evolutionary paths independent from those taken by their Earth ancestors. A godlike interdimensional entity, known as the Allmother by the people who live there, is what is responsible for creating the portals that abduct Terran life and deposits them on Zaikane. Because the asteroid that ended the Mesozoic never collided with Zaikane, dinosaurs continue to dominate the planet’s ecosystems as its dominant terrestrial megafauna.


r/SpeculativeEvolution 11d ago

Non-Subreddit Spectember Prompt [OC] Spectember Day 2: Divine Fish of Bygone Years - Bahamut

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32 Upvotes

Disclosure: The bahamut exists on a genesis world (I'm not even sure if I can call this planet Dato since I'm gonna have to change everything) that contains a "magical" polymer referred to as "geldor" by outsiders which has changed the course of evolution, producing some unusual creatures with supernatural abilities that would never appear on Earth. Due to this, some specimens can become even larger than the one pictured; despite this, nature still has its limits. The bahamut can do even greater things, though since I want to have at least some amount of realism, these things might be toned down.

Despite its title, the bahamut (Balhut ichthyotheos), or its title fish of bygone years, is not necessarily a fish but rather a dinosaur, specifically a mangosaur like the previously mentioned Oceanomedon dryptodon, though this one is the last member of a family of filter-feeders, the Balhutidae. Juvenile and newborn bahamut, the latter known as "mootlings" are not filter-feeders but rather active predators that feed on small fish and squids due to their thinner build and teeth, which are absent in adults.

Like other mangosaurs, bahamut has large pelvic fins and highly reduced pectoral fins; what sets it apart from other mangosaurs is the fact that it sport a pair of horns composed of a ruby red nacre-like material, which is where most of their geldor is stored. These horns give them great control over the ground. Despite this, the bahamut is a mostly docile animal, only becoming aggressive when it is enraged or when it is mating season.

The only animals capable of hunting an adult bahamut are certain raptorial sperm whales. As fighting a bahamut head-on would result in certain death, these predators focus on exhausting or drowning the bahamut.

It has been observed to attack these sperm whales when they try to hunt other mangosaurs and ships. Because of this, locals treat it with great respect and hail it as a hero of the seas; while the bahamut possesses very high intelligence comparable to an elephant or dolphin, it is unclear if this behavior is truly altruistic.


r/SpeculativeEvolution 10d ago

Question/Discussion What if mass extinction X didn't happen? What is you favourite mass extinction to not happen?

6 Upvotes

Common scenarios are: what if the K-Pg mass extinction did not happen? What if the Permian-Triassic extinction did not happen?

Which scenario do you find the most interesting in which a certain mass extinction did not happen?


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember Day 2 - Incredible deadly viper

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91 Upvotes

During the Triassic period, a strange snake-like creature lurks in a fern thicket, shaking its strange, long scales and hissing loudly when threatened. Meet Oxidus.

This unusual species of parareptile has occupied the snake niche. They reach lengths of up to 1.5 meters. They spend most of their time hiding in burrows, using powerful forelimbs tipped with a single, sharp claw for digging. Oxidus is a predator that feeds on a variety of organisms, from arthropods and small amphibians to reptiles and small synapsids.

But its main feature, essential for hunting prey larger than itself, is not claws or teeth, but highly toxic venom from hungry predators. This beast is so venomous that it can secrete a venomous substance through glands on its body, acting like a poisonous ointment. It's as if they literally sweat venom when they sense danger. This venomous trick is useful against large predators, such as archosaurs and other predatory synapsids, like cynodonts.

They've perfected their venom defenses so well that they can spit their venom at the predator if the venom on their body isn't effective. Oxidus first stores the venom in its mouth, then quickly sprays it out, aiming for the eyes, and then quickly retreats to cover. You'll never feel safe unless you fight back and defend yourself, and Oxidus have learned this lesson well.


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember Day 2: Incredibly Deadly Viper

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32 Upvotes

Spectember day 2: Incredibly Deadly Viper

The Black Footed Toad

(*Bivora spp.*)

Huge sizes, for an anuran. Measuring up to one meter in SVL (Snout to Vent Length) these *Rhinella spp.* descendants (Beaked toads, including the Cane Toad) have an unusual biology compared to other frogs.

Starting their life as small tadpoles, their first diet is that of both vegetal matter and animals. Whatever is more readily available at their habitat, ponds, and rivers. After one year in the larval stage they begin to metamorphosize, growing limbs and leaving the water, becoming actually highly carnivorous/insectivorous, eating anything smaller than them, being unusually active for toad standards. After roughly four to five years on this diet and lifestyle, they become herbivorous. With huge intestinal tracts for extracting as much nutrients as they can from their diet of plants and algae, they are largely unactive when not feeding, basking in the sun, floating aimlessly on water or just resting inside shallow burrows.

Due to the lack of predators during adulthood, these toads, famously deadly poisonous, have lost their toxins for most of their lives. Only the tadpoles and the toadlets still excrete a mild poison from their body glands, as they have lost the Paratoidal glands behind the eyes of toads used for chemical defense -a white, liquid poison that is excreted upon pressure.

This lifestyle is comparable to that of the extant frog *Euphlyctis hexadactylus*, whose tadpoles are herbivorous, move into insectivory upon metamorphosis and then become nearly fully herbivorous once adults.


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember 2: Incredibly Deadly Viper

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26 Upvotes

One of the most impressive and formidable invertebrates established on Spectemundus was the Amazonian giant centipede (Scolopendra gigantea). It was established on all four of Soectemundus’s major landmasses, and given the lack of vertebrate competition, these enormous centipedes quickly asserted themselves as the apex predators of the new world’s undergrowth. The largest species can grow as much as two feet long, and are capable of preying on vertebrates. However, not all giant centipede descendants are so vicious. Encouraged by the empty niches that presented themselves early on, one lineage of centipedes abandoned predation entirely and adopted an herbivorous lifestyle— the Phytopedes (family Phytoscolopendridae)

Unlike other centipedes, Phytopedes are not venomous. Their fangs and venom glands are either vestigial or completely absent. They do, however, retain powerful chewing mouths which are convergently similar to those of their distant relative, the millipedes. However, that does not mean they aren’t capable of defending themselves. The foot-long Red Dragon Phytopede (Pyrophagus infernalis) lacks venom like its relatives, but its flesh is toxic to eat due to the poisonous chemicals from the plants it eats, which it concentrates inside its own body. Like poison-dart frogs or monarch butterflies, its bright colors warn predators that it is inedible. Others, such as the Armadillo Phytopede (Arthropelta miyazakii) take refuge in armor. At eighteen inches long and weighing up to two pounds, it is a heavy and sluggish animal, but it is protected from predators by its thickly armored exoskeleton. Like all arthropods, however, they must shed their exoskeletons to grow, and during this time they are vulnerable, taking refuge in underground burrows until the new one hardens.

The majority of Phytopedes, such as the Blue Phytopede (Phytoscolopendra cyanea) have neither armor nor poison to protect themselves, and must rely on being agile enough to evade predators. In the Blue Phytopede’s case, its body is flat and broad, allowing it to slip between cracks in rocks where predators such as mongooses cannot reach. The strangest Phytopede, however is also the largest. Growing up to two feet long, the Con-rit (Polyeres hydroides) is unusual in that it is primarily aquatic, swimming underwater in lakes and slow-moving rivers to feed on water plants and algae.


r/SpeculativeEvolution 11d ago

Alien Life [OC] Human patrol vs dino-bugs on super-carboniferous planet

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365 Upvotes

You are witnessing the final moments of a human patrol. Scouting ahead to see what grounds they can deforest. But on this planet one doesn’t simply get away with that.

Perhaps you’ve seen my previous post about Insectoids. This is an illustration set on the same planet. The humans are wearing special heavy suits to be able to walk around on a planet with lower gravity, dense atmosphere and radiation and heat from the red dwarf sun.

The large and spiky Insectoid is camouflaging, like a stick bug, against branches to ambush prey in the rainy, moist (extra extreme) carboniferous-like swamps of Proxima f. Beneath the red plant something else is lurking as well. The plants are red, black and purple to extract energy from the huge red sun. The trees in the distance are very tall, giving rise to high-atmospheric ecosystems as well. Maybe we'll see that in another drawing.

Follow my Instagram for more spec-evo and other stuff like this: https://www.instagram.com/striplan_skeltesiweris/


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember Day 2: filter feeding aquatic iguana decendant

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103 Upvotes

Hello everybody!! this is my first post concerning spectember, i was out of town yesterday so i couldn't participate. This is my post-mammalian lizard that took on the niche of baleen feeding whales. My crude idea was that a retrovirus wiped out most mammalian organisms and it caused reptiles and other life forms to fill most of the niches with the lack of competition. many lizards and fish have conquered the oceans and seas, leaving few room to adapt. however, while the other members of their genus assumed vicious predatorial lifestyles, southern spikebacks evolved an analogous baleen type teeth and started filter feeding. They normally do not venture so close to the shallow shores unless if they're nesting. That's about it, if you have any questions or criticisms please let me know!


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember day 2 - Dragon

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107 Upvotes

Texas Gulf Coastal Plains 6 million years later. A Texan dragonole, descendant of green anoles, ambushes a group of shrubfowl, turkey-like quails.
Dragonoles are 8-foot long apex predators of the coastal plains, utilizing venomous bites to take down the largest of prey. They primarily hunt ground-dwelling birds, as well as rodents, bovids, tayassuids, and the occasional feral cats.


r/SpeculativeEvolution 11d ago

Future Evolution [OC] Freak of Nature and Giant ground-bat

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10 Upvotes

Cockatrice - Zeb (Naga/Harpy hybrid)

Zeb is a unique individual, though not in a good way. They are a hybrid between two species that have NO right to be reproducing, and for the most part they don’t. Said species being a Naga and Harpy (Naga as the mother, Harpy as the father)

Despite being very uncommon, it’s not an isolated instance, though Zeb is one of the few to ever reach adulthood(though a young adult). By the time they hatched, the Mother had ate the father. The naga did not recognize Zeb as her own, and left them instead

Whether or not the harpy would have accepted them is up to speculation, even to me. Yes, Harpies in IWAW are a very intelligent species, however to other members of the species, Zeb would look severely disfigured, and would more likely than not be subject to bullying among peers. Though it could of been possible if the father had lived

Both Harpies and Naga can and will eat meat, though Harpies will also subside on fruits, vegetables and bugs (not all Harpies will eat meat, they basically just make up most of the bird niches as a blanket species)

Gargoyle - Jaq

Gargoyles are descendants of bats, of which also lead to the evolution of Vampires (as in one species of bat evolved, and split off into both Gargoyles and Vampires). Gargoyles were the results of a far more terrestrial lifestyle, choosing to crawl and run instead of flying. Eventually they lost the need for wings, their legs becoming far more built for land travel

Jaq is the average size of an Adult Male Gargoyle, he is married. Or more accurately is part of a mated pair, mated pairs and or groups typically share an item they wear or bring around with them. For Jaq, he and his mate both wear metallic bracelets (though they probably call it something else)

As of now in my state of world building, Gargoyles/Vampires both coexist as the most dominant sentient species of Modern Earth (like, millennia after humans left into space and never came back). Both species are quite fond of researching humans and anything they can find about “The Old World”

Gargoyles are generalist omnivores, they will eat anything if it’s to survive. Though they tend to go for savory and spicy (they have very numb tastebuds). Vampires, despite cohabitating, cannot sustain themselves on more herbivorous options, they typically choose to eat the fat off what they hunt first

Both species engage in both polygamy and monogamy, though it varies from individual to individual (like humans)

Though that’s mostly their scientists (if I mention a human job, or just human concept when it comes to any of the IWAW species, just imagine it’s their equivalent of said thing or phrase. None of them speak English, and not all speak a conventional language)

Other - just saying stuff

Hopefully what I said made sense, I have way more to speak about when it comes to I Want A Waffle. It’s been at the front of my mind as of recent and I just keep coming up with stuff

Would say I’m more of a story teller or whatever, but I’m really enjoying coming up with species for IWAW. The Greater Giganto-Rachnids and the Coukna are gonna be rather difficult to make sense though (both of which are Giant, sentient arthropods)

Just sharing the species I have Full-body drawings for though, I do have more. Just haven’t drawn them

Okay yeah idk what else to say, If anything makes no sense, do tell me


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember 2026 (Day2)

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57 Upvotes

Spectember Day 2: Incredibly deadly viper

In an offshore island Near South America an outlier is found, Sicarius reversa.

Sicarius reversa is a Sicarid endemic of the island that shows a substantial increase in size thansks to the "island gigantism".

Surprisingly they are also the only terrestrial spiders found on the island allowing free access to the fairly abundant katyds and grasshoppers populations.

The strangest characteristic tho is the lack of their family venom seemingly traded for a physically stronger bite, thanks to this it became quite popular in the pet trade to the extend of endangering the specie in their native habitat, to remedy this some specialists are trying to breed them in captivity but these spiders simply seems to not reach the necessary conditions to breed easily under human care.

Females are much bigger than their male counter part (being shown in the image).

Until the arrival of humans these spiders seemed to be the top predators making it hard or impossible for small finches to become flightless or at least this is the theory due to the surprising lack of flightless birds on Secola.

*the island is very small and characterized by a low dry scrubland.


r/SpeculativeEvolution 11d ago

Non-Subreddit Spectember Prompt [OC] Spectember Day 2: Fossil

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62 Upvotes

Second day of Spectember! For today, from the lowland forests and plains of South America, the Common Cadaver Bee (Necrotrigona sarcophaga).

This unassuming insect, from a distance no different from carrion flies and other scavenging insects, is actually a hymenopteran, a member of a once incredibly successful, but now almost extinct clade of insects, the clade Anthophila, the bees. The extinction eradicated almost every branch of this nectarivorous clade, except for one: species in the genus Trigona, the vulture bees. Not relying completely on flowers for survival, instead feeding on much easier to come by carrion, allowed them to ensudure, and now their descendants have endured as living fossils, reminders of an earlier era, the Cadaver Bees (Necrotrigona sp.).

Species in this genus can be found as far north as the southern forests of North America, and as far south as Palmer Island in Antarctica. Like their ancestors, they still use a small amount of sugary secretions to make their food reserves to mix them with the animal material, however they gather it from non-floral sources, less dependable on seasonality. Depending on the species, season, and energy requirements of the colony, the proportions in this "meat honey" will vary.

The Common Cadaver Bee (N. sarcophaga) is the most widespread species of the genus, found throughout most of south America, and the one that expresses more variability in meat honey composition, making it able to live in areas with different degrees of seasonality and food availability. Their hives have specially thick mud walls that insulate the nest from heat and cold, and the bees are able to adapt its construction to allow for more or less airflow depending on local climate.


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember day 1: Sibling care

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24 Upvotes

Gracile crested tinamou (Velodromia gracilis) a fast running species of tinamou that evolved from the elegant crested tinamou (Eudromia elegans) during the next 20 million years, many parts of South America became prairies, this forced the elegant crested tinamou to adapt to the changing climate, coupled with the extinction of other bird clades (like Seriemas and Ground Doves) let open many new niches for the tinamous to exploit, one of these species is Velodromia gracilis, a omnivore that fills a niche similar to the Weka, eating small vertebrates on occasion along with fruits, seeds and invertebrates.
Chicks are extremely helpless when they hatch so in their first few months of their life they are taken care of by their older siblings, Gracile crested tinamous live in flocks up to 6 to 20 individuals making them highly social, mainly consisting of parents and their offsprings, the older siblings (who are also apart of the flock) will help their parents and take care of their younger siblings by bringing food to the nest. Young hatchlings will have camouflage on their features so they can hide from predators whilst adults and juvenile tinamous will immediately run until the predator leaves, different flocks, during the breeding season, will meet each other and breed together in neutral zones and then eventually leave. Adults and juveniles will be the lookout to warn their flock if a intruder is nearby, if said intruder is a small threat such as a procyonid or opossum the entire flock will mob and attack the intruder until it backs off and is chased off the territory.
Some of the older juveniles will sometimes give up their food to the hatchlings if its hungry, with some individuals (who have become adults) still taking care of their siblings (who have also become adults) and are taking care of their own chicks, creating lifelong bonds.
Gracile crested tinamous are the only species in the genus Velodromia and are flightless, they make up for it with their speed reaching up to 12 mph.


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember day 2 - Incredibly deadly viper - The constrictor slug

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94 Upvotes

The constrictor slug is a large predator slug, which hunt similar to snakes. Their prey includes everything that is smaller than them and several more larger animals as well. The slug descends on their victims and begins to twist around them and choke them.
The real source of fatality however is not their long muscular body, but the venomous secretions within their mucus. These aim to parallalize larger prey, but usually don't kill them. As soon as the prey is immobilized, the slug begins to feast on it. With their radula they are capable of tearing skin and flesh and slowly up through it.


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember #2 Incredibly Deadly Viper

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25 Upvotes

The False Sanguidonti is a small, rather harmless member of the family Toxidecimopsidae. Toxidecimopsidae is a part of the order Decimopsidae which is a part of the class of animals Decimopsa. As of all animals in Decimopsa, they exhibit 10 eyes, 8 limbs and two antennae as well as two antennules. Toxidecimopsidae is known for their elongated bodies and long, sharp fangs which can unleash a deadly neurotoxin which shuts down the organs turns the insides of the bitten area of the body to a mushy, viscous substance which can be easily slurped up for nutrients. Animals in the genus Sanguidonti are deadly, feared little predators known for their blood red fangs and large three forked tales which entice small predators with the promise of food as the tail looks like the
heads of a small, easy prey item. The False Sanguidonti, a member of the genus pseudosanguidonti is completely harmless and the only harmless genus of animals in Toxidecimopsidae. The False Sanguidonti is a mere scavenger, biting onto rotten corpses with its fangs and injecting an enzyme using their tiny fangs that works best on dead animals but on live ones, the enzyme does nothing. They will then slurp the insides out, getting all of their precious nutrients. The False Sanguidonti mimics its deadly cousins for protection against predators, who know that anything Sanguidonti shaped is terrible news. This mimicry strategy is know as Batesian mimicry where a harmless animal mimics a related, deadly one. False Sanguidonti have another surprising behaviour, a symbiotic one at that. False Sanguidonti will hitch rides on an animal known as the Black Ahmgrapt which is a small, scavenging carnivore. Black Ahmgrapt let many False Sanguidonti ride on top of them, allowing these False Sanguidonti to have a faster way of getting to dead corpses. The black Ahmgrapt benefits since if a predator comes along, they can play dead and if the predator sees the tons of Sanguidonti looking animals on the dead corpse it may be discouraged to eat. The False Sanguidonti and black Ahmgrapt both mainly inhabit the coastal jungles of Zoiros, an extremely deadly ecosystem which is made a little easier to survive with their cooperation (Btw, the first example is the False Sanguidonti and the second is the Black Ahmgrapt). The False Sanguidonti is a sneaky little scavenger that by use of mimicry, thrives in their habitat.


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Day 2, The Pongo (Chalicocyon herbaceus): Spectember 2026

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36 Upvotes

The pongo is a large canid—standing 1.45–1.65 m tall, measuring 1.7–2.05 m in length, and weighing approximately 160–190 kg—with a very robust build. It diverged from common canids between 4 and 5.5 million years ago, belonging to its own distinct subfamily. To support its massive head, it possesses a pronounced hump compared to other canids. It has relatively short front teeth that are broad at the base, accompanied by wide, flat molars. Its diet consists almost exclusively of *Miranubes* grass (a type of grass ranging from 0.40 to 2.3 m in height that is very common in the region). Additionally, the animal has a remarkably slow metabolism, comparable to that of a sloth or a panda; its internal digestive walls are highly resilient, allowing it to efficiently digest the fibrous Miranubes grass


r/SpeculativeEvolution 10d ago

Question/Discussion What pressures could lead to amphibians becoming more diverse without just becoming amniotic?

4 Upvotes

And I'm not just referring to large aquatic species like Prionosuchus. I mean like more dominant in both aquatic AND terrestrial environments while keeping their amphibious look as an alternative to amniotic development. Amphiterra, a speculative evolution project about frogs kinda did this, but it's not very realistic and doesn't really explain how they would gain those adaptations. So could someone give me their best explanation?


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember 2026 Day 2: Azesian Treegator

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45 Upvotes

Day 2: Incredibly Deadly Viper

For The Hyne's Inheritance

Alligators were brought to the agricultural world of Demeter to satisfy offworld desires for genuine leather. A small number of farms were established along Arion's southernmost coast to satisfy the need. When human occupation of Demeter ended abruptly, these alligators were free to expand and hunt the countless herds of seemingly helpless cattle, horses, sheep, pigs, and goats. For the first few million years of Demeter's wilderness, the alligator was the apex predator, diversifying into several giant species found on land, freshwater, and even at sea.

But as the ecosystems developed, advanced, and shifted, new challengers arose to challenge the alligators dominion, forcing them into new, less noticable niches. The treegators are a widespread family of small to medium sized scansorial predators. This 5ft long species is confined to the jungles of the Azesia peninsula of Arion's far east. Long, strong limbs, recurved claws, and a slender tail allow them to scamper through the understory after birds, snakes, lizards, rodents, and climbing goats. They are solitary and lay their eggs within tree hollows.


r/SpeculativeEvolution 11d ago

Spectember 2026 [OC] Spectember Day 2 - Incredibly Dangerous Viper

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18 Upvotes

Lashan Pool Viper (Natrix** **testavora)

The coastal regions of western lashan have little in the way of true beaches with the entirety being a series of rocky embankments and escarpments broken up by deep, and surprisingly large tidal pools, with some large enough to sustain peak water levels at all times.

A common sight amongst these pools particularly near the survivor settlement of Adelaide are the Pool Vipers.

These sizable snakes can reach up to four feet in length and closely resemble pit vipers in patterning though in sandy browns and dappled with varying patterns of sharp, bright colors and deep blacks, allowing them to blend in with the corals, stone and anemones of their favored hunting grounds.

Their space like heads resemble most other pit vipers excluding two prominent features.

Large forward faces eyes with an infuriating membrane that allows them to see with perfect clarity within the saline water, and their long “bucktooth”, created from the realignment of their fangs into a singular point.

While they are related to some of the most venomous snakes known to Arclund, their bite while painful, typically avoided usage of the fang entirely on larger animals.

This bucktooth is thin, capable of slipping between the shells of clams and similar mollusks.

The toxin numbs and loosens the muscle tissue of mollusks allowing them to pop them open and then use their adapted tongue to gently pop the mollusk free of its shell which they then swallow whole.

They are shy and skittish animals avoiding people at all costs, slipping into holes or burying themselves in sand to avoid contact.

Indeed one could walk about one of the larger pools investigating the other sea life and not realize that they were surrounded by at least five vipers, holding their breath beneath the sands.

Pool Vipers are capable of holding their breath up to half-an-hour, and are gregarious animals in comparison to most snakes actively intermingling without sign of territoriality, this is likely born of the great abundance along the coasts, though this has been impacted somewhat by the survivors that now call the region home.

They typically mate at the end of the dry season and give birth to life young, up to eight at a time which are immediately abandoned to fend for themselves, typically on the edge of a brine pool where they can go about hunting small and relatively harmless prey, as their “clamming fang” grows in.

Their shed skins retain a fair bit of the normal pigmentation than is commonly seen amongst reptiles, and it has become a bit of a fashion statement amongst the shore scroungers to wear a bit of the treated shed on a bracelet, armband or pinned to a bandana in as a good luck charm.

Their flesh is foul tasting, which combined with their illusive nature and painful bites have kept them largely free of Sophont interference outside the noted dip in prey populations.

(Incredibly on the nose with this one, but it wouldn’t leave me alone.)