13

The big point to consider is why flightlessness evolves. Flight requires an absolutely ridiculous amount of energy, so if there's a way to do without it easily then boom, flightlessness. This usually happens on islands, for reasons I'll get to shortly. Flock of birds gets blown to an island, where there are no predators. They can't get back because they got ...


11

Two of these could be explained by the "aquatic ape" theory: seal-like blubber and being able to drink saltwater. A marine ancestry or amphibious lifestyle (also shore living) would explain how they can deal with the salt; they likely "cry" it out like marine iguanas or crocodiles. Almost everything else (omnivorous, bipedal, similar size ...


6

No special circumstances necessary, this is what is happening with Earth languages, if the circumstances are right. English is a good example - the Great Vowel Shift made the English vowels quite unlike other Germanic languages. Combined with the influx of French words, English does not only sound differently because of her phonetic inventory, but also ...


5

As long as it is to the evolutionary advantage of the creature then yes, it could happen. It makes sense that, for a predator that ambushes it's prey, it would be beneficial for a species to have the ability to work well together, predict it's prey well in advance and perhaps even create tools to assist. The more prey they can catch the better the mutation ...


5

Mangrove Madness & Floating Islands: Is your entire planet Ocean, or are there islands? Mangroves are a source of wood that is intimately tied to the sea. While it is not DEEP sea, many species are dependent on mangrove salt-water "swamps" for critical parts of their life cycles. It would likely fill the role you are looking for, allowing a sea-...


4

They are brachiators Look at living animals. What animals have the longest forelimbs relative to their hindlimbs? Mostly arboreal animals like gibbons and sloths, which use their forelimbs as the main method of climbing about in trees.


4

They are aquatic. https://www.smithsonianmag.com/science-nature/how-do-sea-lions-swim-180963847/ Note in the sea lion, the hindlimbs are much reduced compared to their Carnivoran-body plan ancestors. Your creatures are aquatic, or if not then their very recent ancestors were aquatic. There are many examples of aquatic vertebrates in which forelimbs got ...


4

The ability to recognize yourself in the mirror. This is a rare gift in that only five types of animals on earth posses. Humans, great apes, elephants, dolphins and oddly enough, manta rays. Everything else just ignores a mirror and intelligent creatures like monkeys will think that it is another member of the species and will even pick fights with them. ...


4

Corals are not exactly plants, but they are alive and can be grown with enough patience. They have a variety of shapes, textures, densities and toughness'es. You might also consider some sort of fungi. Prototaxites were prehistoric phalic fungi that could grow 1m (~3.3 feet) wide and 8m (~26.2 feet) tall. They were also very rigid too (they were quite ...


3

Axolotl style! https://news.yale.edu/2020/01/28/tiny-salamanders-huge-genome-may-harbor-secrets-regeneration Behold our distant cousin, the wily axolotl. It has external gills and very spiffy ones too. Except for gills, I personally could satisfy all of your merperson requirments. I am around human height, strength, and intelligence I could swim at least ...


3

I'm pretty sure if you need hands, dolphins can evolve them. It turns out, all cetaceans actually have finger/foot bones in their flippers, since they evolved from terrestrial mammals. And since dolphins use their flippers as swimming aids, they already can move them to a certain degree. Furthermore, mutations happen all the time; 1 per every 100,000 ...


3

Who needs claws? Goat toes rule! Dont mess up the goat toes! Goat toes are already unsurpassed for climbing. Mountain goats are the best mountain climbers there are. https://www.core77.com/posts/18851/biomimetic-designers-take-note-goat-hooves-confer-ninja-like-climbing-abilities-18851# Unlike horses, goats have hooves comprised of two split toes. The ...


3

The variance is unlikely to be substantial. Look at Earth's Many-Varied Splendour! Homo sapiens sapiens has many shades of skin tone - and we all evolved on Earth. Some of us lost our melanin when we moved to different climes - but whether that is purely a matter of insolation or a by-blow from other evolutionary adaptations to new environments is still up ...


3

Their Main Language was Phased out by a Constructed Language Constructed Languages are completely new languages that people just made up. Generally speaking, Constructed Languages fall into one of 3 categories: Engineered languages: Invented to serve a specific purpose. These normally preserve a lot of the original language, but add a lot of new lexicon or ...


3

Shift of religious power / decree from on high / mass education Historically, religious organizations had a large amount of "learned men" who were members of the intellectual elite at the time. Often times, they had skill sets related to language completely unavailable to the common man. For example, until rather recently (on a historical scale), ...


2

Anything on land larger than a cat will die No ifs, ands, or buts. In the actual K-T, large animals across the board were wiped out with little fanfare. These include things like terrestrial pseudo-tortoises, cat-sized multituberculates and marsupials, and other members of groups that otherwise had low losses. So your small generalists like raccoons, rabbits,...


2

The hairy frog, Trichobatrachus robustus, creates retractable claws by breaking the bones in its feet. Many frogs begin their life in a tadpole stage, eventually adding limbs and losing their tail as they age. If there was an evolutionary advantage (such as spending a large portion of their life swimming), the adult form could keep the tail, although it ...


2

Using tools is a classic example of early sentience. Crows can do that but we don't consider them sentient. A primitive language perhaps devoid of syntax and containing only a limited vocabulary is a good sign. Whales, dolphins and laboratory apes all appear to have such languages, but none of them have been granted voting privileges yet. Stepping away ...


2

Unlikely there is no reason to give up functional limbs for poor gliding. Spinning is not something that helps flight it wastes a lot of energy that could go into actual propulsion. it helps maple leaves because they are parachuting and wasting energy is what you want.


2

Okay, so I have played around with various designs and thought about the problem a bit. First off, a disclaimer. These are NOT dolphins. Rather, they are dolphin-like creatures that could evolve on another planet. They couldn't originate from dolphins, because dolphins don't have the necessary requisite parts for these structures to evolve from. So what is ...


2

Mass Extinction of Filter Feeders/Lack of Evolution of Filter Feeders This happened with the introduction of zebra mussels into the Great Lakes. The lakes used to have a number of filter-feeding species, such as paddlefish, but the introduction of zebra and later quagga mussels resulted in the lake being filtered so heavily that they became stripped of ...


2

Humans are pretty good ambush predators. Of course that's not all they do, and I would think that anything that fills the "human" niche would have to be a generalist, like humans.


2

Your hypothetical language family could have formed creoles with other languages. Consider how modern English sounds nothing like Old English- that's because the Norman Conquest brought so much French into the vocabulary.


2

Morphological changes to either hearing or speaking parts What we hear is influenced by the shapes of the ear and internal parts (the eardrum and a few tiny bones, plus the connection to the brain). Similarly, the sounds we make are influenced by the shapes of our mouths, tongues, vocal chords, etc. If a genetic mutation results in substantial changes to the ...


1

As for why greater intelligence would be an evolutionary advantage: Ambush predators could have used greater intelligence to improve their hunting techniques- traps, ranged weapons, and artificial camouflage spring to mind. In humans, developing tools (spears, atlatls, and such) made our basic "chase the animal until it collapses from exhaustion" ...


1

Erm...it might interest/disturb you to know that many species of dolphins have partially prehensile penises. If they're going to evolve manipulators, chances are it will start with something that they can already sort of manipulate stuff with, to get the ball rolling so to speak. Dolphin civilisation is going to be pretty squicky from a human perspective...


1

Not in a normal environment: A lot of people will refer to organisms like what you're discussing as chemoautotrophs, so it's a blurry line. Heterotrophs need to NOT fix carbon to build organics, which is a challenge. The earliest organisms evolved in a nutrient-rich environment because nothing had ever consumed all the natural organics in the environment. So ...


1

I'm sure that it would be biochemically possible for your creature to develop the characteristics you describe, the main issue would be why? What evolutionary advantage would it gain from this? The other issues to consider are the weight of the creature and its environment. If gravitation was less than on Earth it would help a lot otherwise something the ...


1

Yes it is possible for them to coexist. Birds and pterosaurs coexisted there is no reason bats and pterosaurs could not. In fact birds evolved while pterosaurs were dominant. The existence of fliers does not prevent the evolution of other flight. flying animals is to broad a category which group fits each individual niche is what matters and that is not a ...


1

As stated by others, island dwarfism or selective breeding could explain the Goblin's size not growing past that of an ordinary Homo Florensis. Their big noses and ears could easily be explained by living in a dark area; Nixoncranium mentioned dense jungle underbrush. I would like to add caves, though, because small size would be an advantage when chasing ...


Only top voted, non community-wiki answers of a minimum length are eligible