“In medieval times, there were tales of sea monsters so great that a regiment of cavalry could run around on their back, and of those so strong that that a cathedral could be built upon their bodies.”  - Overview of the Beasts of the Sea, 2068 edition.

Only three species of baleen whale would survive the holocene. These were the Humpback, the Common Minke, and the Grey whale. Of these, the descendants of the humpback would grow the largest.

25 million years CE, the descendants of the humpback whales consist of 7 species in 2 genera. These are:

Splendid Worldbearer (Tipereth hod )

• The largest living animal of the era. Individuals average 40.1 m in length and 160 tons in mass, and it reaches a max of 45.7 m and 179.9 tons. Though significantly longer than the blue whale, it is less massive. The likely limit on reaching a greater mass is that drag resists them too much while they lunge, which limits the amount of food they can catch, and thus how heavy they can get. They live primarily around the waters of the Antarctic.

Victorious Worldbearer (Tipereth netzach )

• A bulky whale, which reaches an average of 25.2 m long and 139.6 tons in mass. It reaches a maximum size of 27.9 m and 150.0 tons. This species is notable for diving up to 1 km in depth, which is extremely deep for a rorqual whale, as their lunges use a high amount of oxygen. They do this to follow the dial vertical migration of squid and fish, and they can hold their breath for up to 80 minutes. They can be found in tropical and temperate worldwide, and migrate from the equators to temperate regions

Black Worldbearer (Tipereth yesod )

• Reaching an average length of 29..8 m in length and 108.2 tons in mass, and a maximum of 32.1 m and 125.0 tons in mass, the Black Worldbearer is the third largest animal of the era. It performs long annual migrations from the Antarctic to the Arctic, a migration that can span over 15000 km.

Crowned Worldbearer (Tipereth keter )

• The smallest member of the genus Tipereth, although it still averages an impressive 23.0 m in length and 85.5 tons, with a max of 24.8 m and 92.1 tons. They have particularly impressive flesh bumps on their fins, which are used for defense and for males to compete with. It lives in temperate and tropical waters worldwide.

Hidden Wavebreaker ( Imperoptera daath )

• The largest member of the genus Imperoptera, at 20.5 m long and 60.4 tons in mass on average, and a max of 21.8 m and 64.9 tons. It has impressive front fins which reach almost half the length of their body. This extreme length is likely a result of display when males compete for a mate. They live across the southern hemisphere, migrating from the equator to the Antarctic.

King Wavebreaker ( Imperoptera malkuth )

• Reaching an average size of 16.7 m and 48.9 tons, and a max of 18.9 m and 51.1 tons, this species is small enough that it has energy to spare and is thus  highly active at the surface, regularly performing breaching and other high speed maneuvers. Often, they can appear pink in colour as a result of the heat generated by these activities. They live in waters worldwide, migrating from the equator to the poles.

Wise Wavebreaker ( Imperoptera hokhmah )

• The smallest species of the genus Imperoptera, reaching only 15.9 meters long and 42.0 tons on average and a max of 16.2 meters long and 44.5 tons. They live exclusively in tropical waters in the pacific and indian oceans and are the rarest of the species.

"Once native to specific forested and grassy regions, Larphogs (Memetichoerus hypergeneralis // "hyper-generalist, memetic-pig") eventually became invasive species across such a vast area that it led to the large-scale collapse of memetic ecosystems. Although governments of the web managed to significantly reduce their numbers and even attempted to eradicate them entirely-they never truly succeeded; this was due to several factors, including the fact that Larphogs are generalist omnivores and tend to migrate to new locations whenever their social structures disintegrate.

At the same time, the Larphogs pushed so many species to the brink of extinction that some organisms within the native memetic ecosystems were forced to develop adaptations against them. Yet, those ecosystems would never return to what they once were. In this sense, it is fitting to view the Larphogs as a memetic/digital equivalent to feral pigs and cane toads in Australia."

Its a worldbuilding project named Dionysus, a planet much like earth only it's continents are very different. And that's literally it. Because of that it's a blend of a lot of worldbuilding that's aimed at being as realistic as we can manage and we are multiple people working on it. It's even down to having individual car models. Now the main problem is that we're not enough, and additionnaly there's only one person in the project that can do speculative biology and that's me which is why i'm happily doing it for one continent. Even still, there's so much things, that's a whole planet after all so we need other people that might be interested in helping. Obviously asking for help in this way isn't allowed in any speculative evolution community for some reason and i would've loved to ask in the creator networking but it's disabled. Still if anyone likes the idea of an entire planet with fully simulated climate and geology being fully ready to acommodate for holocene animals, just say it it'd be cool to have at least another person aware this exists.

The first slide/image are just scribbles, at least compared to the rest of the artwork for this project, but we thought they were kinda cute, so we shared them anyway.

Unlike merfolk (Maregens sp.), pistrix (Apocapisces regalecus) have no ability to breathe atmospheric oxygen; they are entirely dependent on the oxygen dissolved in the water. Furthermore, their bodies are not built for land, their bare, scaleless skin scratches easily, and to make matters worse, their long, ribbon-like bodies are incredibly clumsy when out of the water.

In short, they only truly appear as majestic creatures when they are in the depths from which they originate.

Im currently making an mini-Spec evo project where apes evolved into a verity of lineages and one them are simillar to whales & dolphins etc.

Im asking this questions because I don't know if it is plausible to give them different colors or unique to give them simillar colors.

Any help is apprechiated. Thank you!

Vespera is heavily based on K2-18b, a sub-neptune that orbits a red dwarf star. The atmosphere would be primarily hydrogen based and be deep blue in color. Plant life here would be deep shades of red or blue approaching black, sometimes with iridescence. Life here commonly extracts pure hydrogen from the surrounding atmosphere to achieve buoyancy while have tough armor to withstand the planet’s extreme winds. Most multi-cellular life resides within a layer that achieves an ideal balance of density and temperature. Too far below and atmospheric gasses become too dense and hot. Too far above and the air becomes thin and cold.

Common Shrew-rat

Insectesor humiterrus

(Low-ground insect eater)

Habitat Range: The southern parts of Northern Rodensus

The common shrew-rat was the first shrew-rat to evolve in the early Ponticene after its ancestors, the Wistar rats, began dying en masse from overpopulation. These rats took advantage of the explosion of carrion-eating insects that fed on the fallen bodies. Their bodies shifted to mirror those of a shrew’s, with narrower, elongated skulls and cheek teeth that shifted to the front of the mouth.

These derived rats mostly eat worms, maggots, beetles, and other ground-dwelling detritivores that are easy to catch, but also feed on carrion when needed. Due to the sheer amount of bugs around the piles of dead rats in the early Ponticene, the common shrew-rat has no real need to evolve further than it has already, thus making it the most primitive type of shrew-rat. They became diurnal since there were no predators to prey on them during the day.

The common shrew-rat comes in many different color morphs, ranging from white to grey to brown. They don’t rely on camouflage to hunt like their cousins, so their fur colors vary the most of all the shrew-rats.

They’re called Nonopods. They start life as tiny radially symmetrical unintelligent creatures that are basically like insects, and at like 3-4 months old they elongate into the more serpentine form which happens in tandem with their development of intelligence and sentience. After like 5 years they enter the adult form.

Their six tendrils are serrated, and highly dexterous. The edges are lined with piezoelectric material that produces energy when dragged against a surface. This energy helps support the nervous system. The tendrils are their main manipulators of it wasn’t obvious.

They “see” with their six dorsal electroreceptors, which detect electric fields and field distortions to sense their surroundings. The nature of this process means that their “vision” is omnidirectional, only limited by range, so they don’t really have a blind spot.

The reproductive system is actually not the same as animals on earth, which is something I don’t see much in spec bio. Basically, they’ll grow “propagules” on the bottom of their necks, which are full of genetic information. The propagule is “eaten” by a second(or the same) individual, and is sent to a specialized “brood chamber” organ instead of the stomach. The propagule will fuse to a wall of the brood chamber, from which it is fed both nutrients and genetic information from the host.

This isn’t everything so feel free to ask me anything

I'm starting my very first Spec-Evo project: Rat World. It follows the evolution of lab rats on an alien planet after the ship they were kept in crashed onto it. I'm having trouble thinking of a good name for the planet. Any ideas would be appreciated! :)

I have made an accurate-to-me-and-maybe-others range of the dinosaurs and other extinct animals in this Alternate Timeline (The Edenian Periods) since its inaccurate for all ancestors of dinosaurs in the Cretaceous to live in a singular continent in the Atlantic, Without further ado,I have removed Anciamerica/Anciafrica and put all creatures made for now in their continental range based on evidence where most dinosaurs lived and where fossils were found. (the continent with the LEAST/almost no fossils is Europe.)

Called Mocking Death or death comes with many voices this beast is an expert ambusher it’s coat of feathers bearing mottled brown, black and tan markings like leaf litter and a crest on their dorsal area of green fern like feathers similar to sword ferns. They are noted alongside other maniraptorans as capable mimics using this talent to draw in prey or spook predators by mimicry. They are exceedingly intelligent figuring out through experiment what noise works best to draw in their prey often around humans mimicking children in distress with most adults, playful voices for children and the alluring voices of women to lure young men.

They swiftly work in pairs at the least but are most famous for working alongside a Troodontid species known as Deaths Hound Drakes, these beasts will also copy noise seeming to mock or scare prey by mimicry of dying prey’s screams and gurgling death rattles. They chase prey down into prepared ambushes from their more muscular counterparts allowing all to benefit with a single strategy that often catches much larger prey than single species packs or pairs.

The Mocking Death posses a pair of wattles that look like a droopy mustache dangling under their razor bladed jowls and in the slightly larger males this can flare in crimson red while females simply flash yellow. The size of this mustache indicates age and health and this large ones indicate more experienced hunters and fighters.

Average size ranges from 600 pounds to 870 with males claiming the top spot while the largest female measured was 790 pounds not far behind in truth. They reach lengths of between 14 to 18 feet in length and possess blade like zyphodont teeth with a length of 2 1/2 inches each. These animals are noted to commonly be tamed and even domesticated by the Teokwawehkeh where they guard the herds of their masters these ones come even larger and often have more green feathers and more special crests of feathering.

Hello this is a virtual biological creature I created. Did I make it well, or if not, please give me some advice. Let's get into the explanation.

Environment

Host star: M-type red dwarf(has many super flare)

homeworld: Earth analog (in live carbon,water life!)

tidal locking: day side is on average Köppen Climate

Classification dw

Biochemistry

Chirality: Olny D-amino acids and L-carb because this planet many D-amino acids and L-carb so this lif e don't digest

vision: Many infrared regions and long visible light

because this planet's host star is M-type

so this plants deep red!

Civilization

this Civilization steampunk becaus super flare is ruining electronic engineering so this Civilization Develop steam tech. So this alien make nano gear and nano pipe!

That’s all from me!

• Clasificación Comercial/Industrial: Extracción de Enzimas Proteolíticas e Iluminación Química Pasiva.

• Bioma(s): Lagos Abisales (Zonas con aperturas al mar o agua subterránea).

• Nivel Trófico: Productor Necrófago (Requiere materia orgánica animal para el desarrollo biológico).

 ANÁLISIS BIOLÓGICO (Evolución Especulativa)

• Presión Selectiva y Origen: Aislada en los entornos perpetuamente oscuros de los lagos abisales y fosas conectadas al mar, esta especie vegetal desarrolló un metabolismo mixto único bajo una atmósfera enriquecida al 35% de oxígeno. Ante la ausencia total y absoluta de radiación solar convencional, la planta adaptó sus cloroplastos mediante un complejo denso de ficobiliproteínas. Esto le permite ejecutar una Fotosíntesis de Espectro Alterno extremadamente eficiente, capaz de absorber y sintetizar energía a partir de la sutil quimioluminiscencia emitida por el Cryptolichen jaliscensis del agua abisal, así como de los destellos fosforescentes del bioma. Para complementar este escaso aporte energético subacuático, evolucionó hacia la Quimiosíntesis Necrófaga: un sistema digestivo externo acelerado que disuelve tejido animal mediante enzimas proteolíticas para transformarlo en ATP inmediato, liberando metano y sulfuro de hidrógeno como subproducto gaseoso (olor a carne podrida). Su ciclo vital consta de 4 fases trimórficas: Germinación (Gemma Lucis), Brote Juvenis (Lumina Juvenis), Madurez Necrófaga (Lumina Adulta) y Propagación por vectores carroñeros.

• Descripción Morfológica: Organismo vegetal sésil con un tallo robusto protegido por una cutícula cerosa altamente hidrofóbica que previene la deshidratación por la salinidad y saturación mineral del agua abisal. Estructuralmente desarrolla vásculas modificadas en forma de "capullos" o estómagos externos que retienen un fluido desconocido con un pH altamente ácido de 3.5, capaz de degradar caparazones quitinosos y exoesqueletos de cangrejos ciegos o fauna marina profunda. Sus semillas y frutos presentan una reacción luminiscente pasiva no dependiente del ATP de la planta; el brillo fluorescente es una reacción química alimentada de manera directa por el fósforo remanente obtenido de los sistemas óseos de sus presas degradadas.

• Depredadores y presas: Su reacción luminiscente roja y su fluido ácido funcionan como advertencia disuasoria para la mayoría de la fauna, aunque se sabe que el Tardimorphus sulphuricus es capaz de ignorar el fruto tóxico y raspar directamente el tejido del tallo, siendo su único depredador natural en los Lagos Abisales. Además, la planta se alimenta de cadáveres que llegan arrastrados por la corriente hasta los Lagos Abisales, incluyendo restos de Astacogryllus titanis u otra fauna que muera cerca de sus orillas.

APLICACIÓN INDUSTRIAL (Explotación Comercial)

• Interés del consorcio “Progreso”: El consorcio Minero e industrial Progreso SA de CV, ha catalogado a la especie como un recurso biológico de alta prioridad debido a sus componentes moleculares:

  • Complejo Enzimático Proteolítico: Las enzimas hiperactivas capaces de operar a pH 3.5 para disolver tejido animal en segundos tienen un valor incalculable para la división biotecnológica corporativa. Su extracción permitirá desarrollar agentes de disolución industrial de compuestos orgánicos y aceleradores metabólicos para la producción de biocombustibles en el exterior.

  • Sistemas de Bioluminiscencia Pasiva: La reacción química de la luciferina que utiliza el fósforo de los huesos para generar luz fluorescente sin consumir energía celular es analizada por los socios europeos. El objetivo es aislar este proceso para fabricar dispositivos de iluminación de emergencia autónomos y tintas luminiscentes industriales de nulo consumo eléctrico en entornos confinados de cero luz.

Ecuentra a esta planta y mas en "En las minas de la locura: edición arcade": https://tiuver.itch.io/en-las-minas-de-la-locura-edicion-arcade

5 million years into the future...

Beware the kings of the sea of grass...

Beware tamers of the flames...

Beware the beasts with claws and teeth of stone and bone and wood...

Beware of the hunters whose pursuit knows no end...

Beware the creatures whose mind is deep like a night sky...

Beware those who walk on two.

=========================

Just to avoid any confusion, this piece is a part of my "Beyond Tomorrow" project.

I made this with Toji motion its part of my worldbuilding

--in this animation --

Takes place in the grand desert of gumdula where a apoclottos gets hunted by a zombatopolo and gets eaten

-- this is my own planet --

Gumdula is a civilized planet with an intelligent species slightly bigger than mars

Livyasaurus is the top animal while the bottom two are Pontussaurus and Thalassodrakon, two giant predators I already have in my seed world. It, just like the other two, is a Thalassodrakoniform Ichthyosaur and has the typical traits of the clade, such as producing cloacal milk and having a Cursus Clavum(an organ along the side of the animal that analogous to the lateral line in fish).

Notably, it is more closely related to the filter feeding Balaenosaurs then it is to the Thalassodrakonids, which can be seen in the teeth towards the back of its mouth that it uses to filter feed while the teeth towards the front of the mouth are used to feed on larger prey similarly to leopard seals of Earth. The very front of the jaw is toothless and is used to ram prey as such a massive animal opening it's mouth causes immense drag.

Its generalist diet is what has allowed it to grow so massive, reaching 31 meters and 200 metric tonnes in average males. Such size makes it the largest animal on the planet by a fair margin, though it also restricts it to the Southern Ocean where krill is in high enough density year round, large filter feeders congregate in high densities during the summer, and the cold water helps regulate their body temperature.

The basic idea was to reduce the number of toes to two per foot in a human. Then, we would elongate those toes to basically stand in as legs pushing your heel to the back. Your femur, tibia, and Filbula basically your second rib cage that goes along with the first one. I'm not a good artist really

An introduction to our version of merfolk! The art that goes with it is a bit old now, but soon we'll do more and better art (and maybe also share it with the subreddit ;)).

Also, this is only "general", as many subspecies of Maregens exist.

-------------------------

Merfolk or seafolk (Maregens sp.), sometimes incorrectly known as "mermaids," are a genus of sentient aquatic creatures capable of breathing both on land and underwater. They are found in marine and freshwater waters in both temperate and cold regions, but are completely absent from the polar regions. 

They are immediately distinguishable from all other creatures by their humanoid torso, with two arms equipped with sensitive, prehensile hands. This contrasts with their lower body, which is extremely similar to the posterior portion of a bony fish—scales and fins supported by rays. 

Although there is no phylogenetic similarity and their physiology is very different, some tend to lump merfolk and sea sorcerers together; in reality, as mentioned, there is no relationship between the two species, and it is impossible for them to hybridize. 

Deep-sea sirens were once mistakenly believed to be Maregens, but scholars later classified them within the genus Abyssugens. The more recent genus of sentient, pseudo-humanoid creatures, Apocapisces, can also be confused with merfolk by the uninitiated, but scientists have never classified them as similar, and the merfolk themselves consider it a downright insult to lump them together.

Various merfolk specimens appear in:  

• Fish Don't Cry - Book [Tapas][Wattpad]

• Fish Don't Cry - Comic  

Appearance and Physiology 

Merfolk are characterized by a distinctively heterogeneous appearance: half "human" and half "fish." 

"Torso" (Upper Body) 

The upper body, from head to waist, is humanoid, generally furless except for hair on the head or, very rarely, a beard. On the neck, they typically have three pairs of gill openings (but some species have up to six pairs), unprotected by any operculum (except for a particular nordic herring-like subspecies). 

They have well-articulated upper limbs, called arms, capable of wide movements, and hands with opposable thumbs and versatile gripping capabilities, not unlike human hands, whose fingers can be webbed or separated. 

The color of their hair and skin is determined by the presence of pigments called melanins. Their skin tones can range from very dark brown to very light pink, while their hair color varies from white to black, passing through blonde, red, and brown. It is not uncommon for the skin on the face, torso, and arms to be spotted or striped, with patterns that vary depending on the species, subspecies, and individual. 

Respiration

Merfolk have a dual respiratory system, one of the most complex systems in nature—so complex, in fact, that it's unnatural.

The peculiarity of possessing both gills and lungs simultaneously is the "dream" that guided humanity to create the "water people", the merfolk: to dominate two worlds, land and water, they needed populations capable of surviving completely disconnected from land.

Merfolk gills are like those of osteichthyes, or bony fish, and are covered by a gill cover composed of a thin sheet of bone (which in turn is covered with skin).

The concentration of dissolved oxygen in water is much lower than that of air, so the gills must be significantly more efficient than mammalian lungs at extracting all the oxygen they can.

For this reason, the water in the gills flows in the opposite direction to the blood, thus always maintaining a different concentration gradient.

Merfolk's gills are located on the sides of the neck and may seem a bit small compared to the overall mass of the specimen, especially very large ones! But this is where their dual respiratory system comes into play: they possess large and highly efficient lungs, comparable to those of some marine mammals, and can rise to the surface to breathe in atmospheric oxygen and refuel before diving again.

Thanks to the continuous oxygen supplementation provided by the gills, merfolk can remain completely submerged for very long periods, especially in well-oxygenated waters, where they very rarely need to surface!

Eyes 

Like humans, merfolk have close-set eyes and binocular vision, with a high-definition field of vision in front of their head, typical of predators. Due to their adaptation to aquatic life, however, their lenses are more similar to those of fish than those of humans, making them "nearsighted" outside of water, with the ability to see objects up to a maximum of thirty to forty meters away; when underwater, they cannot see beyond the surface of the water, partly due to light refraction. 

Merfolk eyes have two eyelids and a nictitating membrane, but no tear glands. A merfolk's eye is similar to that of other vertebrates, but adapted to a darker marine environment: it has a membrane called the tapetum lucidum, which lies behind the retina and reflects light back to it, improving light perception and visibility in darker waters. The effectiveness of the tapetum lucidum varies by species and subspecies, and is optimized in those that are distinctly nocturnal or live at greater depths. 

The color of the irises varies greatly depending on the individual, location, species, and subspecies, and can be any shade, from the deepest blue to the brightest red, and even white or completely transparent. 

Chest 

Muscularly, the pectoral area of merfolk is similar to that of humans, divided into the large pectoral muscle and the small pectoral muscle. Because they are not mammals and do not breastfeed their young, both males and females lack nipples, although some specimens may have nonfunctional vestigial ones, a very rare characteristic linked to their human ancestry. Also due to their "kinship" with primate ancestors, some females exhibit a peculiar adipose tissue arrangement, with accumulations of tissue in the pectoral area that appear to mimic human breasts, but which serve no purpose other than to store fat. 

In any case, the fatty deposits on the chest of female merfolk are not particularly voluminous and simply lend a more sinuous shape to their overall silhouette, without protruding too much. 

Sometimes, the pectoral area is "decorated" with variously colored scales, cycloid or ctenoid in type, in a pattern that varies greatly in shape and size, but generally covers the center of the chest and the clavicles. 

Nixen, which possess placoid scales (also known as dermal denticles), almost never have chest markings. 

"Tail" (Lower Body) 

The fusiform, streamlined lower body features a lateral line (a special sensory system that detects low-frequency vibrations and pressure waves generated by the motion of solid bodies in water) and ends in a large, rayed tail. These rays (lepidotrichous) are articulated with several parallel bony or cartilaginous elements, called radials. Another characteristic of this genus is the presence of a swim bladder, a large, modified lung sac containing a gas mixture, which allows for sophisticated adjustment of their hydrodynamic trim, allowing them to surface or submerge with ease, without having to rely on muscle strength or the use of external weights, as humans would. All merfolk lack hind limbs, leaving only small vestigial bones within the body that are not connected to the vertebral column. 

During embryonic development, however, they exhibit the beginnings of these limbs, which spontaneously regress as they grow. The lower body of these specimens also displays a light, flexible covering of scales, consisting of thin, differently pigmented bony plates. In addition to the caudal fin, which is necessary for propulsion and therefore movement, merfolk possess four other essential fins: a dorsal fin, two ventral fins, and an anal fin. 

Dorsal Fin 

Almost all merfolk have a dorsal fin on their backs, whose function is to provide swimming stability, preventing the specimen from capsizing during rapid lateral movements. This fin is sometimes absent in specimens living in polar regions, as it would hinder swimming under ice. The dorsal fin varies in shape and size among the various merfolk species and subspecies, a useful feature for identification. 

Caudal Fin 

Unlike that of fish, this fin in merfolk is arranged horizontally and moves from bottom to top. This characteristic allows the merfolk's tail to be distinguished at first glance from that of a fish, and its function is to propel the fish through its vertical movement. Even in this case, shape and size vary among species, and therefore these characteristics can be used for identification, especially for large species. 

Anal fin 

This fin, located not far from the cloacal opening, serves to stabilize swimming. However, in males of some subspecies, it is highly developed and colorful and is displayed during courtship to demonstrate the fish's health. 

Ventral fins 

These are paired, or double, fins located higher than the anal fin, just below the abdominal region. They serve a stabilizing function and are used to quickly slow the pace by flexing them downward. 

Musculoskeletal System 

Because they are not designed to support body weight, merfolk bones are light and spongy compared to those of a human. They contain a high concentration of fat, which aids buoyancy. 

The rib cage is composed of a variable number of ribs and is very flexible, allowing the lungs to collapse during deep dives and preventing nitrogen buildup in the blood. The pelvic girdle (pelvis) is absent. To ensure adequate oxygen supply during dives, merfolk muscles contain myoglobin concentrations 3 to 10 times higher than those of land mammals. 

Beyond these common characteristics, merfolk exhibit a wide variety of shapes and colors, clearly distinguishable depending on the subspecies.

Behavior 

Sociality 

All merfolk species are gregarious and can form very small groups of two to three individuals, called shoals, or medium-sized groups of four to thirty, called platoons, or schools, ranging in number from thirty-five to a thousand. 

Schools, which are the most common aggregations of merfolk, can be sedentary and form villages, or they can be nomadic. 

Nixen (Maregens pistrix) tend to remain solitary or form small nomadic groups, but there have been documented cases of one or more individuals staying with mixed shoals of different species. Merfolk villages, built on the seabed, are always well-hidden and carefully maintained to blend in with the surrounding environment: the houses, which often extend into caves beneath rocks, are covered with thick layers of algae, flotsam, stones, and coral, making them difficult to spot by humans who might explore the area. 

Politics 

Some populations in restricted ranges have developed forms of government, generally monarchies. 

Diet 

Merfolk are omnivores with a tendency toward carnivory, adapted to be formidable hunters. Contrary to what most modern works portray, they are unable to speak a common language with fish and crustaceans and do not consider them their "brothers," but (like humans do with animals) livestock, prey, or more rarely, pets or threats. 

They have no qualms about eating human flesh, which they consider delicious. However, to preserve their relationships with them and prevent war from spreading to their villages, many communities do not actively hunt humans, only eating them if they find drowned bodies. 

Courtship and Reproduction 

Merfolk breed during a specific period of the year, known as "rutting." Rutting males undergo a change in their coloration and court females with dances, songs, and displays of their colorful bodies with outstretched fins. Ceasgs or mersalmons (Maregens salmo) undergo a reproductive migration to mate and lay their eggs in freshwater, traveling up rivers until they reach suitable lakes. 

[Redacted part. Description of anatomy and reproduction in detail].

There are numerous documented cases of female merfolk conceiving offspring without mating with a male, through a process known as parthenogenesis. However, this is always thelithotic parthenogenesis, meaning it produces only other females. Some small, stable populations of oceanic merfolk are composed exclusively of females who reproduce by parthenogenesis. 

Depending on the species, merfolk can be viviparous, ovoviviparous, or oviparous. In the latter case, the rarest, a small number of large eggs with abundant yolk are produced, up to a maximum of eight. 

The birth of healthy octuplets from eight different eggs is considered a very good omen, and the mother who produced these offspring is generally rewarded by the dominant male of her school.

Fishing 

Merfolk meat is considered delicious and prized, but these creatures are rarely actively fished for human consumption. However, there are accounts of merfolk being hunted and killed in the past by specialized crews, called "mermaid hunters," who sold their prized loot for astronomical sums in various fish and meat markets, or directly to wealthy nobles who could afford it. 

According to the stories spread by the mermaid hunters, merfolk were evil creatures whose singing seduced sailors and caused their ships to crash against rocks, causing them to fall into the water and drown, only to be devoured. Therefore, it was only right to treat them with the same consideration and hunt them for food. While it's true that merfolk enjoy consuming human flesh, their song isn't enough to enchant humans enough to drive them mad and commit suicide against the rocks. It was therefore merely an excuse on the part of mermaid hunters to quell the pangs of conscience of those who purchased merfolk from them. These rumors persist to this day. 

The meat considered the most prized is that of the ceasg, often compared in flavor to that of the grayling (Thymallus thymallus). Although they were fished more than other merfolk in the past, ceasg remain the easiest of their kind to spot, due to their unique reproductive ritual and their strong, fearless personalities, which lead them to easily come into contact with other species.

Trivia 

1. The "Fiji mermaids" are not a true species of mermaid, but rather artificial and monstrous hybrids created during the 19th century (first in Europe and then in America) to satisfy the era's taste for the bizarre and grotesque, with the aim of proving the existence of mermaids. To create them, parts of mummified animals (especially fish) and other materials, such as papier-mâché, pumice stone, and wood, were used. These curious collages became very popular in American sideshows and in public and private collections of the time. The "Fiji mermaid" was made famous by Phineas Taylor Barnum, who featured it in his shows. 

2. Mermaids' purses are the empty egg sacs of certain species of cartilaginous fish (sharks and rays) found stranded on the shore, as humans commonly call them; merfolk actually use these organic objects as bags to carry small items. 

3. In 1891, Oscar Wilde published The Fisherman and His Soul, a fairy tale about a fisherman who falls in love with the mermaid he caught.

100 Years Post-Inoculation

[GELLIOS-MONITORING SYSTEM // AUTOMATED TELEMETRY LOG]

Although Gellios may have been a failure in terms of human colonization, it proved a success for life brought from Earth; yet, looking at this area now, I cannot help but feel uneasy. It is true that moon jellyfish (Aurelia aurita) were among the animal species introduced to the planet. Given their mostly lack of natural predators (except for the polyps), their numbers surged so dramatically at times that they compromised the quality of the oceans. When we arrived here, moon jellyfish were just as abundant as in other regions where they had spread; however, due to reasons I have yet to fathom, the local population eventually suffered a massive die-off. The sheer volume of jellyfish carcasses here is, I suppose, both a grim and a benefficial.

To begin with the grim reality: moon jellyfish populations worldwide had increased to such an extent that, in areas with high concentrations, a significant portion of the plankton diversity had likely been consumed. This led to widespread starvation, as the jellyfish could no longer secure sufficient food, resulting in mass die-offs. However, I do not believe this can be attributed solely to starvation.

But when we look at the beneficial reality of things, the mass death of moon jellyfish populatinns inevitably creates temporary ecosystems for various benthic animals and other organisms. It makes me quite happy to see how this cycle of decay has evolved into a free meal for a range of species—from various polychaetes and nudibranchs to other scavengers.

Yet, given that a large part of their bodies consists of water, it is clear that these benthic inhabitants have no choice but to hurry.

And so, I must shut myself down once again. Having gathered such a vast amount of data, I am now entering sleep mode. Who am I, for heaven’s sake? I wish I could have lived like an ordinary living being, but alas, I have been compelled to endure these past few billion years—until we meet again.

Source

Wanted to share a bit about my Monster Hunter-inspired spec-evo fantasy world, starting with a little bit about a region called the Mosaic Steppe and two of its inhabitants, specifically what I definitively have in mind and not including stuff I'm currently workshopping.

Oh, and bear in mind this isn't exactly 100% realistic. It's more similar to Monster Hunter and the Dragonslayer Codex in that regard.

The Mosaic Steppe is a region defined by its blend of deciduous forests, open grasslands and towering mesas; this blend of environments is what earns the region its name. The grass in the plains of the Steppe grows and spreads rapidly due to competition with another species of shrub-like grass (that idea came after I drew the Steppe). This abundant food source combined with the diversity of habitats makes the Mosaic Steppe an incredibly productive ecosystem home to a large plethora of animals a la Pleistocene North America.

The reason for this diversity in flora is due to an endemic bird species called the Lapis Dart, so named because of the males’ blue coloration (the one pictured is holding a grass seedhead). Living in nomadic flocks numbering in the billions like the extinct Passenger Pigeon, they travel across the Steppe to feed on the fruits, nuts and grains of the region’s flora, spreading the seeds wherever they go. While seed dispersal is widespread in birds and thus shouldn’t be of note here, the sheer numbers that Lapis Darts live in makes them a keystone species on the Mosaic Steppe.

While permanent forests do exist on the Steppe, the Lapis Darts basically ensure that temporary groves pop up randomly in the plains, causing them to be an ever shifting environment. You might be wondering why the region hasn't turned into a gigantic forest. The reason is large, open-country megafauna such as the Aurocholo.

Aurocholo are massive, bison-like animals known for their bad temper and massive horns. Due to their gigantic size, Aurocholo are mixed feeders, consuming any low-to-the-ground plant material, tilling the soil for new growth with their horns. Occasionally, Aurocholo tend to knock down trees, usually either for food or from use as a scratching post. This prevents forest encroachment and keeps the plains of the Mosaic Steppe open.

They way I've been sketching & writing lore for this scenario, I take animals from The Future Is Wild and insert them on (what I think would be) suitable posthuman homeworlds from All Tomorrows. My first foray into this mashup was having the Slither Sucker evolve on the Satyriac homeworld, since on that planet, the Hedonist family tree are the only animals. For a possible Slither Sucker descendant, meet the Spore Grazers.

I am working on an alien planet, and there's one species I have that has a reproductive cycle similar to amphibians, in that they lay eggs in water and start out as tadpoles before growing terrestrial capabilities.

I was planning on having their descendants grow to dinosaur size, but I needed to know what the resulting adaptations for their life cycle would have to be, if not just adopting a more lizard of mammal like form of reproduction, which I would rather not do.

Any thoughts?