Caveat: no corn

On DeviantArt and YouTube as Concavenator: sometimes I draw and write about speculative biology, life on other worlds and in the far future, and the history of life on Earth.

[o-craven-canto]

Hiya.

o-craven-canto here, on DeviantArt as Concavenator. I have a Neocities website that is only just sketched.

I'm a working biologist, specialized in systematic and evolutionary zoology, which I think is the most beautiful thing in the world. I find the timescales and strange mechanisms of evolution especially fascinating. I also enjoy reading about history and language, but those are very much not my field.

Related, I like to make excessively detailed infographics on (mostly) biology and history, which I'm told people like. I'll probably sell printed copies of them at some point.

Lifelong devotee of speculative biology, a hobby focused on the design of imaginary but scientifically plausible creatures, both for fun and as a teaching tool for actual biology. If you'd like to learn more, I have lists of links and resources here and here.

I've written A Matter of Time, a book detailing a fictional history of humankind from the near future to the end of the universe (previews here).

Other speculative projects of mine include Settlers from the Deep (Earth resettled by aquatic and cave-dwelling species after a severe mass extinction); Tagra (a civilization of sapient dinosaurs inhabiting Antarctica just before it’s covered in ice); Gods of Salt (the “““real”““ history of human origins); Ea: Our Second Chance (life on an Earth-like planet colonized by ideologically fractious humans).

I also write and draw various shorter-form stuff, mostly set in distant futures or alternate worlds.

If for some reason you want to know my tastes and opinions: #aesthetics, #asks, #discourse, #plato on the road, #sorry, #stuff I like, #my work

[o-craven-canto]

Let's imagine an alternate timeline where there's more than one unambiguously sapient species (or "obligately sapient" as Biblaridion calls them) that coexist with us. Not offshoots of humanity like other extinct Homo species, but unrelated animals that evolved sapience independently. What candidates would you choose? The most obvious ones for me are dolphins, elephants, corvids and parrots.

Hmm. Sapient, tool-using species tend to be intrusive*, so if we exclude closely branching species of the same genus, I think we might be unlikely to find them on the same landmass.

If tool-using humans quickly expand to fill Afroeurasia, that means we're more likely to find our para-humans in the Americas or Australia (other landmasses are probably far too small). Corvids and parrots are found in both, and there were crown-group elephants in the Americas until recent times, so those remain candidates.

I'd like to submit procyonids (raccoons & kin) in the Americas and phalangerids (e.g. the brushtail possum) in Australia as candidate para-monkeys: they navigate complex environments, are actively foraging omnivores, have energy-rich diets, and raccoons can clearly manipulate objects too (see the recent discussion on marsupial intelligence). If they started evolving into a more social direction 20 or so million years ago, procyonid and phalangerid para-humans might not be completely out of the question.

Of course you can sidestep the whole landmass issue going into the sea. Dolphins, as you mentioned, and I think sea lions might also be a decent candidate (maybe less so than dolphins, but with the added benefit of being able to come to land for, e.g., fire). Perhaps sea otters that expanded their feeding range through tool use? Semiaquatic monkeys like the crab-eating macaque that fully took to the sea?

* See the idea that humans might have taken over a particular "cognitive (ecological) niche" (Pinker 2010, Whiten & Erdal 2012) that includes cumulative culture through extended cooperative childcare, cooperation among non-kin with division of labor, complex tools, theoryof mind, and syntactic language. It may be that once a species or group of species has taken this niche, it's difficult for any other to get in it.

[o-craven-canto]

@c-elegans971095

Good point. I focused strictly on birds and mammals but there are some accounts of surprising cognitive abilities elsewhere (e.g. tegu lizards, elephantfish, jumping spiders). AFAIK, the main issue with cephalopods is lack of post-hatching parental care, which means no cumulative culture (and often death right after spawning), which means no cognitive niche. All mentions of "parental care" in this 2001 review of cephalopod reproduction seem to refer only to eggs, as do all other such references I've found. Tool handling is known in octopodes and complex huntng tactics in squids, so if a cephalopod line starts teaching skills to its offspring they have a decent chance.

[o-craven-canto]

Cleaned the fridge and sent an application to Inprnt for an art shop. Let's see if this miserably hot weekend starts well after all.

[despazito]

The fossil record we're leaving behind from the anthropocene is gonna be so fucked

[despazito]

Digging up the UK in future millennia: temperate rainforest....glaciers.. temperate rainforest.. sudden disappearance of all trees. all megafauna gone. one billion sheep bones. asiatic deer. parrots. occasional macropod. giant redwoods. coati. hawaiian goose.

[o-craven-canto]

Someday, the Frogs would dig deeper in the ground, and would discover whole geologic layers haunted by those nameless beings, together with their effigies carved in marble, cast in bronze and in gold; with pieces of glass and ceramic, of grainy plastics, of wires and rings of vulcanized rubber, with immense deposits red with iron and blue with copper, and with unexplainable concentrations of radioactive materials. Someday, they would find their ruins on other worlds.

-- A Matter of Time, my extremely cool future-history novel 👀

[o-craven-canto]

The sloppy orthography in this text I have to transcribe makes me [sic]

[o-craven-canto]

Happy Friday the 17th to everyone!

[official-kircheis]

kinda lazy worldbuilding to have every terrestrial vertebrate be a tetrapod

[o-craven-canto]

They're trying their best :(

[o-craven-canto]

Let's imagine an alternate timeline where there's more than one unambiguously sapient species (or "obligately sapient" as Biblaridion calls them) that coexist with us. Not offshoots of humanity like other extinct Homo species, but unrelated animals that evolved sapience independently. What candidates would you choose? The most obvious ones for me are dolphins, elephants, corvids and parrots.

Hmm. Sapient, tool-using species tend to be intrusive*, so if we exclude closely branching species of the same genus, I think we might be unlikely to find them on the same landmass.

If tool-using humans quickly expand to fill Afroeurasia, that means we're more likely to find our para-humans in the Americas or Australia (other landmasses are probably far too small). Corvids and parrots are found in both, and there were crown-group elephants in the Americas until recent times, so those remain candidates.

I'd like to submit procyonids (raccoons & kin) in the Americas and phalangerids (e.g. the brushtail possum) in Australia as candidate para-monkeys: they navigate complex environments, are actively foraging omnivores, have energy-rich diets, and raccoons can clearly manipulate objects too (see the recent discussion on marsupial intelligence). If they started evolving into a more social direction 20 or so million years ago, procyonid and phalangerid para-humans might not be completely out of the question.

Of course you can sidestep the whole landmass issue going into the sea. Dolphins, as you mentioned, and I think sea lions might also be a decent candidate (maybe less so than dolphins, but with the added benefit of being able to come to land for, e.g., fire). Perhaps sea otters that expanded their feeding range through tool use? Semiaquatic monkeys like the crab-eating macaque that fully took to the sea?

* See the idea that humans might have taken over a particular "cognitive (ecological) niche" (Pinker 2010, Whiten & Erdal 2012) that includes cumulative culture through extended cooperative childcare, cooperation among non-kin with division of labor, complex tools, theoryof mind, and syntactic language. It may be that once a species or group of species has taken this niche, it's difficult for any other to get in it.

[spaceexp]

A plot of all objects in the Universe

[str-ngeloop]

would love to see this bad boy's original caption and source....

[drawn-from-the-ground]

All objects and some questions

We present an overview of the thermal history of the Universe and the sequence of objects (e.g., protons, planets, and galaxies) that conden

Here ya go! https://pubs.aip.org/aapt/ajp/article/91/10/819/2911822/All-objects-and-some-questions

[shabbytigers]

We present an overview of the thermal history of the Universe and the sequence of objects (e.g., protons, planets, and galaxies) that condensed out of the background as the Universe expanded and cooled. We plot (i) the density and temperature of the Universe as a function of time and (ii) the masses and sizes of all objects in the Universe. These comprehensive pedagogical plots draw attention to the triangular regions forbidden by general relativity and quantum uncertainty and help navigate the relationship between gravity and quantum mechanics. How can we interpret their intersection at the smallest possible objects: Planck-mass black holes (“instantons”)? Does their Planck density and Planck temperature make them good candidates for the initial conditions of the Universe? Our plot of all objects also seems to suggest that the Universe is a black hole. We explain how this depends on the unlikely assumption that our Universe is surrounded by zero density Minkowski space.

……. i don’t know what i expected

[o-craven-canto]

Found an earlier version graph in a paper from 1979 (which is in the bibliography of Lineweaver and Patel's), in which objects are measured in terms of the fine structure constants α (electromagnetic) and αG (gravitational), using the proton mass and hydrogen atom radius as units

[o-craven-canto]

There's also two really cool interactive visualizations:

The Triangle of Everything

An interactive chart plotting every object that can exist by mass and size — from quarks to the observable universe.

[gift-from-the-bellow]

USERNAME LORE GIVE IT TO ME NOW YOU ALL

[o-craven-canto]

Anagram of my forum/DeviantArt name, Concavenator, which in turn is after this guy

[mellifexfarm]

prickly icky

[o-craven-canto]

Reminder that a dodo was basically just a giant pigeon chick

(tree source)

[self-loving-vampire]

When people are like "This is bad because it went horribly wrong in this movie I watched" I can't take it seriously.

Do you realize you're arguing from fictional evidence?

The fact that Dark Dungeons exists doesn't mean playing a TTRPG is going to end up with demon magic cults and suicides. Writers can just be ignorant or biased actually.

[notatzimisce]

They made a horror movie back in the 70s about what terrible things would happen if we started putting electrodes in people's brains to treat their neurological disorders. The original novel was written specifically because the author saw this treatment being developed in real life and thought it was scary and thought he needed to turn people against it.

Turns out what happens is "fucking nothing, except for treating neurological disorders".

[o-craven-canto]

By the same author as Jurassic Park, even.

This is your scheduled reminder that the first message you should learn from Jurassic Park is "dinosaurs are fuckin' awesome", and the second message is "if you need to contain large dangerous animals, use brick walls and not electric fences that will instantly lose effectiveness at the first bad weather, ffs this was a solved problem in the Neolithic"

[o-craven-canto]

Wing geometry of flying vertebrates

A diagram of the wing shape of flying vertebrates, including birds (black), pterosaurs (blue), and a bat (red). Based on JMV Rayner (1988), "Form and Function in Avian Flight", fig. 14D & 16D (link) and MP Witton (2008), "A new approach to determining pterosaur body mass and its implications for pterosaur flight", table 4 (link). The two axes represent wing loading (body weight divided by wing surface) and aspect (length-to-width ratio), independent from overall size. While the distribution of species is mostly continuous, there are "regions" corresponding to particular wing shapes and flight styles. Starting in the lower-right region of high loading and low aspect (small, short wings and heavy bodies) we find danger flyers like gamefowl (e.g. pheasants, turkeys) and, presumably, the pterosaur Dimorphodon. I call them this (replacing Rayner's uncharitable "poor flyers") as these species only fly in short bursts to escape ground-based predators. This is not a primitive trait: both gamefowls and Dimorphodon have ancestors that were more sustained flyers. If we keep wing loading high and increase wing aspect, we move upward into the divers: birds like ducks, grebes, puffins, and auks that dive into water to feed and so have relatively heavy bodies. Narrow wings help them acquire speed as they plunge into water. The highest wing aspect is found among marine soarers, of hich the purest example is the albatross (and the pterosaur Nyctosaurus, who has the highest wing aspect ever recorded). At the edges of this cluster, gulls transition between marine soarers and aerial predators, and gannets between marine soarers and divers. Aerial predators, who hunt in mid-flight, have low loading and mid-to-high aspect to be as fast as possible. Insectivores like swifts and swallows have narrow, swept-back wings, whereas bird-eaters like harriers and falcons have broader wings. Here we also find the tiny insectivorous pterosaur Anurognathus. Beneath, with the lowest wing aspect, we find thermal soarers, who fly long distances over land exploiting rising thermal currents. They tend to have broad wings with slotted ends, like storks and vultures. Here we also find the largest bats and giant azhdarchid pterosaurs such as Quetzalcoatlus. Finally, near the center we find versatile, unspecialized terrestrial flyers like parrots and pigeons. Hummingbirds, with a unique hovering flight, appear near the divers, though for rather different reasons.

(see deviantArt page for picture references)

EDIT: replaced "saltuary flyers" (a calque on my Italian "volatori saltuari") with "danger flyers" as it turned out that "saltuary" is an extremely rare word in English. Thanks, @bluebelly-sun-serpentine!

[shoogachi]

semi-aquatic human spec

[requiem-on-water]

"The Soul's Journey" (2025) by Chiharu Shiota | Ph: Charles Roussel

[o-craven-canto]

Everybody's saying "if all the blood vessels in your body were taken out, they'd reach this and that", but only Chiharu Shiota is actually trying

[the-delta-of-worlds]

Worldlines twist and grow like fungal hyphae through the hyperspace, sometimes branching away, sometimes drawing closer if they develop along similar lines. Normally, once separated, worldlines would never cross. But there are worlds were the meddling of powerful species, now departed, weakened the barrier between realities.

The Delta of Worlds is one such place, where the result of very diferent courses of evolution have fallen through the pores and now coexist. Whoever is responsible for the Delta of Worlds has not been seen for millions of years, but They must have been very interested in the forms and varieties of sex, for that is the running theme of most species who fell through...

This blog is dedicated to exploring concepts of speculative biology, especially NSFW and sexually explicit ideas, informed and inspired by the immense variety of forms that evolution has given to sex and reproduction in our own world. They will focus on alternate versions of life on Earth, more or less close to humankind.

Under creation. See index of creatures.

[o-craven-canto]

Pterosaurs aren't serious creatures

(front view of Nyctosaurus gracilis, PhyloPic, CC-BY 3.0, Gareth Monger)