RECOMMENDED READING LIST ON EVOLUTION:
> The Selfish Gene - Richard Dawkins
> The Extended Phenotype - Richard Dawkins
> The Revolutionary Phenotype - J.F. Gariepy
> Evolution and the Theory of Games - John Maynard Smith
> Animal Signals - John Maynard Smith
> The Red Queen - Matt Ridley
> Mendel's Principles of Heredity - Bateson & Mendel
> Population Genetics: A Concise Guide - John H. Guillespie
> The Largest Avian Radiation: The Evolution of Perching Birds, or the Order Passeriformes by Jon Fjeldså, Les Christidis, and Per G. P. Ericson
>The Cambrian Explosion: The Construction of Animal Biodiversity by Douglas Erwin
>Carboniferous Giants and Mass Extinction: The Late Paleozoic Ice Age World by George McGhee Jr.
>Triassic Life on Land: The Great Transition by Hans-Dieter Sues
>On the Prowl: In Search of Big Cat Origins by Mark Hallett and John Harris

What's an animal alive today that could converge into an ankylosaur niche?

>>5101999
pig

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>>5101999
armadillos
its already happened before, it can happen again

>>5102038
being armored isn't a niche formfag

>>5101999
Pangolins
Armadillo Lizards
Snapping turtles
Thorny devils
Horned lizards

All of those actually grow big scales/osteroderms/spikes on their bodies and tails and could probably evolve a club.

>>5102048
what did I just say about armor and niches, formfag

>>5101999

turtles like Meilania

>>5102087
>>5102041

Well the exact niche of ankylosaurs is unclear. We understand them as low browsers, so technically a horse is an akylosaur analogue

>>5101996
op what the hell is that thing

>>5102164

What is Mako? luman

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>>5102164
oh wouldn't you like to know

wasn't there a game where you built your own animals? Spore?

>>5102041
uh, "herbivore that focuses on being slow and defensive instead of cursorial" is a niche, actually.

not a fan of the aislop, it's nonsense because it disregards the actual evolution part of speculative evolution and is frustratingly derivative.

Why are creatures in speculative evolution so hideous?

>>5102311
That's a strategy. What does the herbivore specifically eat

>>5102313
I think the slop is bait. I recognize the creatures and the project they're from has a strict policy against AI. Unsure why slopify them

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>>5102313
>>5102325
cope

>>5102328
you didn't even try with that one

>>5102289

yup

>>5102323
plants, you fat faggot
stop being obtuse

>>5102322
they're trying too hard to be "realistic"

>>5102386
>doesn't know the difference between a browser and a grazer or a generalist and a specialist

>>5102416

Again, horses.

>>5102423
Horses are specialists.

>>5102323
What's the difference between a strategy and a niche? Don't tell me you think niche is exclusive to how they obtain food, because that's extremely silly.

>>5102459
A niche is what specific resource the species exploits. And a specific subset of plants is as much a different resource from other subsets of plants as insects are from rodents for carnivores

>>5102488
Well, that's wrong. A niche is what role an organism fills in an environment or ecosystem. That typically includes what foodstuff they consume, but it does not require that inclusion for it to be a niche.

>>5102515
The fact that polar bears will eat you isn't your niche

>>5102533
You're being very silly.

https://alpha.sagan4.org/wiki/Dioramas

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>>5102776
Not even gonna bump the thread with an example?

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future

>>5103134
what's with the multiple eye creatures?

>>5103445
just report it for trolling and ignore it, he's not posting any actual spec evo and is not interested in discussing it.

>>5102041
>>5102323
>>5102416
>>5102488
>>5102533
What a sperg lmao

>>5103558
I was hoping there actually was some thought behind it or justification like maybe a concept of earth undergoing a cataclysm that wiped out every vertebrate and evolution having to start over or so

like I get it's AI, but in theory you could use AI to make a sort of "good enough" sketch of ideas you had
always a shame when AI images turn out to have just no thought behind them

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>>5103558
>>5103682
you do realize those are classic sagan 4 dioramas """remastered""" with AI right

>>5103822
Why not post the originals then? they are much more appealing

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>>5103824
idk "future" or smth here's another one

>>5103822
Putting an existing work through a slop filter and then not discussing it at all is not suitable for these threads. It's just regurgitating things, especially considering the filenames most likely in a malicious manner. It's just trolling.

New Noterra video on not!cryogenian microorganisms
https://youtu.be/uuhW4BwN90A

New Kaimere videos
https://youtu.be/qT1EL5niQ9k
https://youtu.be/yTutXAv4IQA

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>>5104196
>kaimere
speaking of things that aren't spec evo...

>>5104196
Noterra really deserves far more views
single celled spec-evo is fascinating

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could animals ever transition to live in space, the same way aquatic species moved onto land?

>swifts already spend 10 months in the air without needing to land
>suddenly a predator appears that mostly hunts swifts at lower elevation
>selective pressure for swifts that fly higher and land less often
>eventually you reach the first bird that gives live birth, with the offspring remaining in a pouch to avoid falling before their wings are ready, finally enabling them to keep airborne for their entire lives
>when attacked by predators, they ascend to where the air is too thin for them to follow, holding its breath for over 30 minutes like an emperor penguin
and you could call them martlets because https://en.wikipedia.org/wiki/Martlet

>>5104470
the air being thin doesn't just make it harder to breathe, it also makes it harder to avoid stalling, requiring increasingly more energy to maintain the necessary velocity to stay at that altitude or increasingly massive wingspan

then there's the issue that it gets cold fast at higher altitudes again requiring more energy expended to stay warm
all while your ability to generate energy is reduced significantly by your lower oxygen intake

and you still need to descend to get food because there's no possible ecosystem that high since it completely lacks autotrophs to form the baseline, which means exposing yourself to predators, while being hamstrung at lower altitude by the requirements to survive at extreme altitude, and you are not capable of ascending fast enough to escape danger and you're also not big enough to simply avoid predators entirely due to the requirement of being extremely light weight to be even capable of remaining airborne

there's simply no good way to achieve this

>>5101996

New Age of Monotremes megavideo: https://www.youtube.com/watch?v=RFBaVIsWQCc&t=692s

>>5104470
I think this might be achievable by pests that hitch a ride with humans going to space. Not sure exactly how they'd adapt but it seems plausible.

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>tits
>lays eggs
harpies are fucking monotremes

>>5102164
It's called Italian brainrot

>>5105820
>>tits
>monotremes
you'll lap up her milk off of her bare, nipple-less flat chest and you'll like it. I'm sure I would.

>>5105820

You do realise there's a number of extinct mammal groups that laid eggs right?

>>5105982
Mammal-like reptiles?

>>5105982
yes but as you said those groups are extinct so they cant possibly be harpies

>>5106709

Said groups became extinct fairly recently though. You could have your harpies be the last representatives of said group.

>>5106677

I mean animals like Castorocauda and Morganucodon

>>5104494
/thread
>>5104470
>live in space
also,choose your words better next time. High altitudes≠space
no living beings can survive in outer space,let alone thrive

>>5106751
>no living beings can survive in outer space,let alone thrive
In theory it would be possible through genetic manipulation create some kind of microorganism capable of withstanding vacuum and use special pigments to withstand the radiation and gain energy from it

but even if you could do that they still completely and utterly lack nutrients, so you pretty much need them anchored to a comet for them to have any chance, and it needs to be a comet or waterbearing asteroid rich in carbon and other necessary minerals
you could in theory simplify a creature to use as little elements as possible but even then extracting those from an asteroid or comet rich in them is exceedingly hard constrained by a simplified bodyplan

>>5105820
There's been more bird species with teeth or that produce milk then there are or have ever been mammals with feathers.

>>5107665
wait which bird species produce milk, as in actual milk?

>>5107686

Not actual milk but crop milk is common among birds like pigeons, penguins and flamingos

>>5107815
oh sure I knew about that one but I was just wondering if some bird convergently evolved true milk
which is not entirely unlikely considering that siphonops annulatus actually went and evolved proper milk despite being a caecilian

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>>5101996

New entry in Lemuria https://lemuriaspeculative.wordpress.com/2026/03/12/freshwater-dugong/

I'm hoping to make a litrpg about a Zerg like alien and I'd like your guys thoughts in regards to this stat sheet.

#Specimen Profile: Hybrid Tyrsect Drone

Classification:
- Taxonomic Species Designation: Tyrsecta (Drone Caste, Young Adult Phase)
- Specimen ID: TDR-047-HYB
- Observation Date: Cycle 47.892

Morphological Analysis:
- Body Plan: Hexapod (six-limbed) ambulatory structure, approximately human-scale (1.8m length, 1.2m height at shoulder).
- Cranial Features: Raptor-like skull with; ant-derived mandibles at the corner for grabbing and pinning in place (lancing edges, tensile strength ~350 MPa).
- Exoskeletal Armor: Sparse chitinous plating, covering vitals and sitting well away from joints.
- Unique Morphology: Abdomen gaster acid gland reservoir (capacity: 1 L corrosive fluid, pH <2).
- Locomotion: Agile, predatory gait; capable of bursts up to 60 Km/h.
- Sensory Apparatus: Compound eyes (360° field), 20/190 vision; chemoreceptors on antennae for pheromone detection.
- Vital Signs: Metabolic rate elevated (energy expenditure: 2.5x baseline drone); regenerative capacity moderate (minor wounds heal in ~48 hours).
- Genetic Integration: Rodent cerebrum xenograft stable; hybrid vigor noted (enhanced neural plasticity).
- Acid gland ejection range: 6-8m; toxin profile: Hydrofluoric-based, tissue dissolution rate: 10cm3/min.
- Synaptic Relay Cluster: Range 12 meters; Low frequency; Baseline drone hive-mind relay organ.

Behavioral Assessment:
- Cognitive Status: Independent Thought unlocked; no longer hive-dependent.

Quantitative Stats Overview:
| Attribute | Value | Notes |
| Strength | Mandible crush force: 1,500N; lift capacity: 300kg. |
| Agility | 16 m/s; jump height of 2 meters. |
| Durability | Chitinous armor rating of ~350 MPa. |
| Intelligence quotient | 25; Post-mutation; basic problem-solving emergent. |
| Kill Count | 19 tyrsect drones. |
| Malleable Biomass Accumulated 16 liters of tyrsecta flesh. |

>>5108738
looks interesting, what is it for?

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Rhinoailurus amurensis, a newly discovered Early Oligocene felid from the Russian Far East that may reshape understanding of early cat evolution. Unearthed in 2023 from the Bureya River formation, the fossil includes a well-preserved skull and partial skeleton. While similar in size to a modern bobcat, the animal’s most striking feature is its highly developed nasal structure, unlike anything previously seen in related carnivores, immediately drawing scientific attention.

Anatomically, Rhinoailurus was a capable carnivore with strong jaws, sharp teeth, and a body suited for agile movement, but its defining trait was its extraordinary sense of smell. Its nasal cavity was vastly enlarged and complex, suggesting an olfactory ability far surpassing that of modern animals—even exceeding that of a bloodhound. This implies it was a scent-specialist predator, likely relying on smell rather than speed or vision to locate prey and navigate its environment.

Its evolutionary position remains debated. Some analyses place it as a sister taxon to Proailurus, an ancestor of modern cats, while others argue it belongs to a farther separate, extinct feliform lineage. Regardless, Rhinoailurus lived in a mixed woodland-savanna ecosystem during a time of climatic change, where its advanced olfactory abilities would have been advantageous. Ongoing research aims to clarify its classification and further explore its sensory adaptations, with hopes that additional fossils will shed more light on this unusual predator’s place in evolutionary history.

>>5111588
>aislop

Biogeographically, the current continents do not allow for as much variation as would be possible; Eurasia is very vast and located at relatively high latitudes. Imagine if the continents were more fragmented, with more islands, and if most of it were concentrated in the tropics. We would have an even richer global flora and fauna.

>>5111714
Floating islands would work. Rafts of nitrogen fixing reeds would provide shelter for seagoing and castaway animals without changing ocean currents.

>>5111714

Cretaceous to Eocene in our history

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>>5101996

New entry on Multituberculate Earth: https://multituberculateearth.wordpress.com/2022/03/31/gondwanatheria-world-domination/

>>5101996
What sort of pokemon are these?

My own spec evo project isn't going that well...I am so lost now

>>5112817

What is it and what happened?

>>5112962
I'm completely lost about atmospheric pressure, currently on a revamp yet again but I don't actually understand what higher atmospheric pressure do past the initial observations, it's genuinely hard.

>>5113101
https://worldbuildingpasta.blogspot.com/2025/11/climate-explorations-pressure.html

this has a fairly decent exploration on different atmospheric pressure effects on climate in a very much readable format

>>5101999
rhinos
just have them grow osteoderms

>>5113259

Depends on the rhino. Some rhinos are grazers while others are browsers, unlike ankylosaurs

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Scud posting begins now.

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>>5114553

>>5114555
>>5114553
Now do gigascud

>>5114555

Question: how do the gamete scuds enter the adult scuds? Do they live in water?

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Wanna design an oceanic mustelid that doesn't look like seals or whales. I figure going for max eyesight works best here, to achieve a unique look. I don't know about the rest of the body though.

My apologies for making a thread without realising there was already a spec evo thread.

Thought about a very intelligent Amphibious Cetacean that lives in an alternate Antarctica where Aegicetus descendant survived there by hybridising with a Stem Simocetid and a Stem Aetiocetid roughly 34 million years ago therefore gaining the ability to echolocate, produce wax esters and develop a melon and baleen to hunt Krill and Squid in the Southern Ocean while crawling on land/ice to breed and establish mating rights. Lobodont Seals therefore didn't evolve since Mixocetid Whales took the niche already by the Oligocene.

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>>5116476
The species that contributed to the genome.

>>5101996
New Alien Biospheres - Alien Anthropology video
https://youtu.be/lgtuefqQs1s
https://youtu.be/4FGQefqIRxw

>>5116474
could aim for basilosaurus. I like the creepy face.

>>5116532
I thought this was already over and done with? I wish it was with how much identity politics he pushes into everything, it was hilarious when he made a blm disclaimer in one of his random conlang videos.

>>5116573
https://www.youtube.com/watch?v=o04Y6W90J60
kek this was pathetic

>>5116474

Looks like a cookie cutter shark

>>5116532
>>5116573
it's still nice to have a project that works from first principles rather than just being a seed-world

has anybody here talked about this? seems like they're building up for a revival of the future is wild

https://www.reddit.com/r/SpeculativeEvolution/comments/1kekdpd/the_greatest_of_news_new_the_future_is_wild

https://www.youtube.com/@OfficialTheFutureIsWild

heard that they may be involved with the studio that did the wwd reboot. also personally i believe the redesign in the subjectively vids may be used in the new doc

>>5116764
>>5120066
stop trying to shill your tranny fanfiction here, keenan.

>>5101996
What if Earth (Terra) had an advanced intelligent futanari elf race that evolved from pseudo-synapsid-like monkeys/bandicoots during the late Jurassic to mid-Cretaceous period and established early civilizations in the Paleogene period? How would a few domestic dinosaurs, pterosaurs, herbivorous crocodiles, giant amphibian-like waterhorse (kelpie), and non-archosaur reptiles adapt to their new masters?

>>5111588
Pink Panther but fused Vemon (Spider-Man) and Bass (Mega Man)?

>>5121542
>The sentient species of Earth (No Humans ever evolve, still remain a monke state), earth becomes home to five major intelligent lineages, each arising independently.

1. Aelonar (Elves) — Synapsid Arboreal Sapients
Origin: Late Jurassic pseudo‑synapsids

Traits: hermaphroditic, arboreal, bioluminescent skin, long lifespan

Technology: copper bronze organic engineering

Culture: canopy cities, ecological stewardship, philosophy of memory

Range: global, with subspecies on every continent

Status: dominant civilization

2. Corvidans — Intelligent Bird Tool‑Users
Origin: Cretaceous corvid‑like ancestors

Traits: flight, advanced problem‑solving, vocal mimicry

Technology: stone tools, woven structures, fire mastery late

Culture: oral tradition, sky‑navigation, clan‑flocks

Range: Eurasia, North America

Status: secondary sapient species, often in alliance or rivalry with elves

3. Cetari — Marine Cetacean Philosophers
Origin: Paleocene proto‑whales

Traits: sonar language, deep memory, long‑distance communication

Technology: none physical; advanced social and philosophical systems

Culture: oceanic councils, migratory knowledge networks

Range: global oceans

Status: equal‑level sapients, but non‑material civilizations

4. Burrowers — Rodent‑Derived Thinkers
Origin: Paleocene burrowing mammals

Traits: subterranean architecture, tactile language, hive‑like cities

Technology: stone shaping, fungal agriculture

Culture: collective memory, underground archives

Range: Africa, Eurasia

Status: hidden but influential civilizations

5. Saurians — Surviving Maniraptoran Descendants
Origin: small feathered dinosaurs that survived K–Pg

Traits: bipedal, feathered, sharp cognition, pack‑based

Technology: bone tools, early metallurgy in volcanic regions

Culture: honor‑packs, volcanic shrines, sky‑rituals

Range: South America, islands of Tethys remnants

Status: regional powers, sometimes hostile

>>5121542
>Asia
Aelonar homeland

Corvidan sky‑cities in the Himalayas

Burrower archives beneath Central Asia

Coastal Aelonar–Cetari diplomacy in the Indian Ocean

>Africa
Rift Valley Aelonar kingdoms

Burrower megacities under the Sahara

Corvidan desert‑adapted flocks

Cetari councils off East Africa

>North America
Redwood Aelonar realms

Corvidan forest‑canopy cities

Saurian enclaves in volcanic zones

Burrower tunnel‑nations in the Rockies

>South America
Aelonar jungle empires

Saurian volcanic kingdoms

Cetari coastal alliances

Burrower fungal‑forest networks

>Europe
Aelonar stone‑fungus kingdoms

Corvidan alpine sky‑forts

Burrower subterranean libraries

Occasional Saurian migrations

>Australia
Desert Aelonar

Saurian island‑tribes

Corvidan coastal navigators

Burrower oasis‑tunnel cultures

>Antarctica
Ancient Aelonar homeland (Eocene)

Now inhabited only by migratory Cetari and hardy Corvidans

Ruins preserved under ice

>>5121578
>Late Jurassic (160–145 mya)
The proto-Aelonar humanoids evolved from hermaphroditic pseudo-synapsid sentients.

Early corvidan ancestors appear

>Early Cretaceous (145–100 mya)
Aelonar intelligence increases

Maniraptoran ancestors of Saurians diversify

>Late Cretaceous (100–66 mya)
Proto‑elves and proto‑corvids survive K–Pg

Small feathered dinosaurs survive in isolated refugia

>Paleocene (66–56 mya)
Burrower ancestors evolve

Cetari ancestors return to the sea

Aelonar spread across Asia

>Eocene (56–34 mya)
Aelonar canopy cities

Corvidan sky‑cultures

Cetari oceanic councils

Saurian volcanic tribes

Burrower fungal agriculture

>Oligocene (34–23 mya)
Bronze Age for Aelonar and Saurians

First inter‑species diplomacy

Corvidans develop written sky‑glyphs

Burrowers create subterranean archives

>Miocene (23–5 mya)
Global trade networks

Maritime Aelonar–Cetari alliances

Saurian volcanic empires rise

Corvidan star‑navigation perfected

>Pliocene (5–2.5 mya)
Climate cooling

Desert Aelonar cultures emerge

Burrowers expand tunnel‑nations

Saurians retreat to volcanic refuges

>Pleistocene (2.5 mya–10,000 BCE)
Ice Age diplomacy

Cetari become climate prophets

Aelonar bronze metallurgy peaks alongside iron work tech discovery

Corvidans develop complex mathematics

Saurians survive in isolated pockets

>Holocene (10,000–2000 BCE)
Agricultural revolutions across species

Monumental architecture

Global councils of sapients

No humans anywhere (currently monke)

Earth shaped entirely by multi‑species civilizations

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imagine a world, millions of years in the future...

the 'evolution discovering technology' trope is the best

>>5111841
>>5121542
Right timeline.

>>5121663
the thing i like the most about this series is how, even if full of bullshit theories, some done for production reasons, it really managed to make future earth look like an outlandish, alien place, even the 5 million year future period. the early 2000's CG and the location choices do help in that regard, but even then some scenes and settings still look very cool.

>>5112540
this looks like someone didn't know how to properly draw an okapi and gave it horns on top of that

>>5121542
Now perfect for a domesticated companion species in alternate‑evolution world. Unlike most crocodyliforms, that animal is Simosuchus.

Small size — about 0.7–1 meter long

Chunky, rounded body that looks unintimidating

Short, blunt snout that reads as “cute” to most intelligent species

Herbivorous diet — easy to feed, no hunting instincts

Slow, calm movement — safe around futa children

>Possible domesticated varieties
Garden Simosuchus
Small, colorful, bred to nibble weeds and keep gardens tidy.

Lap Simosuchus
Round-bodied, extremely docile, loves warmth and cuddling.

Scout Simosuchus
Slightly longer legs, used to sniff out edible plants or track trails.

Mosaicback Simosuchus
Bred for decorative, patterned osteoderms; kept by nobles or priests

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>>5121910
>safe around futa children
what
what the fuck are you talking about

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>>5114555
>sapient
>r-selected

>>5121981
Language! He talked about pug face croc.

>>5122097
to be fair about half of the planet's human population reproduces via r-selection and are technically sapient

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They are unimaginably wealthy.

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These little mites are only 6 inches tall and have technology they couldn't reinvent.

>>5113101
Think about the deep sea. Usually you have different species in different pressure ranges. If you take deep sea creatures to higher sea levels they die due to explosion by internal pressure.

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>>5101996
Bat are cool.

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A planet significantly larger than Earth but with almost nothing but ocean. Lot of powerful dust storms. No end to their sky.

>>5122376
>If you take deep sea creatures to higher sea levels they die due to explosion by internal pressure.
actually they tend to be fine believe it or not, having lower pressure on the body than normal is a lot less rough than having more pressure on the body than normal. Still not good for them, of course.

How crocodiles evolved in a convergent way like pterosaur did?

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I feel like I'm going insane failing to figure this out. So in short I'm trying to create as simple of a seed world as possible. Unicellular protists in the form of zooplankton and phytoplankton as the base of the marine ecosystem, vampire squids as the multicellular marine detritivore to be focused on, bryophytes and lycophytes as the smaller and larger primary terrestrial producers respectively, and some sort of terrestrial arthropod that eats detritus to also be focuses on.

>reddit space

Now obviously that sounds easy, finding an insect that eats detritus might as well mean looking under the nearest rock in my backyard. However insects and arthopods in general tend to have this big restraint that cephalopods do not. They are tiny. So in order to solve this you obviously turn to the largest living terrestrial arthropod, the coconut crab. From what I've read it's managed to get to that size due to its highly derived branchiostegal lungs which makes sense considering what I've heard about arthropods and oxygen. However I then thought about the largest ever terrestrial arthropod, arthropleura, which like all other myriapods breathes passively through less efficient spiracles than even insects. So I think that can't be right, and I look into why arthropleura became so much larger than any of its insect or arachnid contemporaries, and in doing so I read about exoskeletons not being able to support larger body sizes as internal skeletons, so the several hundred legs and simplistic bodyplan of arthropleura helped them carry their bodyweight. Sure, why not.

>reddit space

But wait, were that the case, why is the coconut crab way larger than the largest millipede alive today? So oxygen must play a role in bodysize right? Except arthropleura it turns out lived well into the Permian when atmospheric oxygen levels nosedived compared to the Carboniferous. (1/?)

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So then I read about competition from vertebrate predators that could attack the arthropods after they molted, outcompeting them in the process. As well as that, many aquatic crustaceans are hardcapped in bodysize by the energy exerted due to the need to shed their exoskeletons. So I think, what arthropod do I know of that has specialized structures for breathing, simplistic bodyplans with many legs, and unique molting adaptations to aid in growth?

>reddit space

Isopods of course! They have pleopodal lungs, 6 pairs of legs at birth that later changes to 7, and they shed only half of their exoskeleton at once. They seem like the ideal candidate right? EXCEPT APPARENTLY FUCKING NOT! They are so goddamn tiny, and I had no goddamn clue why. So maybe it's the lungs. Pleopodal lungs are modified gills on the abdomens of terrestrial isopods that are widely considered to be more efficient in oxygen intake compared to, say, arachnid book lungs (although definitively less efficient than the highly vasularized branchistegal lungs of hermit crabs).

>reddit space

So why aren't isopods at least as big as arachnids? Turns out their lungs are partially external which makes them vulnerable to dessication (although that wasn't a problem for arthropleura but whatever), even then there's arid-adapted isopods that fix that by making an internal tracheal system and it still doesn't result in them being bigger than a fingernail. Maybe they are just late to terrestrial environments and that's why? Well how could that make sense when FUCKING COCONUT CRABS EXIST!?!?!

>reddit space

Isopods first came up on land at the Carboniferous-Permian boundary, and coconut crabs only appeared in the last couple million years, so what giiiiiives maaaaaan. Why are arthopods so fucking weird dude??? Can somebody who knows more about arthropod anatomy please explain this to me? I am such a goddamn retard istg.(2/2)

>>5122826
well part of it is that arthropods don't tend to leave the best fossil records so who knows if coconut crabs really are a new thing or if it's just something crustaceans convergently stumble upon once in a while

who knows, might even have been bigger coconut crab equivalents, current size is nowhere near theoretical maximum