Which animal will replace humans as Earth's dominant species? This scientist has an idea

But they
Have extremely short lifespan so a limited capacity to learn (1-2 years)
Don’t raise their offspring, in fact after mating/laying eggs they naturally die, so no knowledge sharing
Are extremely solitary and don’t have social bonds or do anything socially, so little communication/passing of knowledge
- On top of that, they might not even survive the CO2 and consequent ocean acidification. If humans were to get eradicated by some super plague, then octopi might still stand a chance, but the points you mentioned are going to make that journey much harder.
  
  I worked as an intern at a lab studying octopus vulgaris.
  They are extremely sensitive to all sorts of things in the water. Keeping them well is very difficult. Although I would imagine if there are big but gradual changes in water environment, they would have a chance of adapting faster due to short life cycles and the fact that mating creates hundreds of thousands of eggs.
- Octopi would rule the world if they had any sort of generational data transfer.
- I’m not even convinced that intelligence is a requirement to be the dominant species. Intelligence is so expensive that nature rarely ever selects for it.
  Trilobytes did pretty damn well for a hell of a lot longer than we have so far. I think we need a stronger working definition of “dominant” in order to judge any candidates.
  
  But the reason he gives for them becoming the dominant species is their intelligence.

Eighteen paragraphs of throat clearing to get to the point of the title.
- It's the new norm. Worse when it's video format and, thus, hard to skim.
  
  Sponsorblock and YT's "relevant metrics" or chapters are life savers lol.

It's unlikely an aquatic species can achieve technological breakthroughs needed to spread like humans can. It would be very difficult for them to build fires, smelt metal, and create the advances based off of those tools.
While they can be extremely smart and adaptable, it's difficult to imagine how a species like that could develop machines.
Sure, there's possible ways around it, like natural vents and geothermal power, but why would they utilize these resources without a benefit like cooking?
- Shells or coral could serve as early tools, but (just my opinion) I feel it's a little human-centric to assume fire and metallurgy are required to progress. Just because we did it that way, doesn't mean another species would have to.
  
  Fire and tools were what we needed to become the dominant species, as they gave us power to take down the larger megafauna.
  
  I've spent a lot of time thinking about this exact subject, and I dunno. As much as I consider it, as abstractly as possible, I have considerable difficulty finding an alternate route to significant human-like dominance. Fire and metallurgy are just so incredibly useful across so many domains. I challenge you to present a reasonable alternative route.
- whatever comes after us will have to make due with whatever crap we leave behind. There wont be enough natural resources left for them to use if they want to do anything larger scale or advanced
- A symbiosis between octopi and dolphins 🤔
- Every RPG has taught me that coral swords are a thing.

They are marine which makes fire impossible which severely limits industrial advancement. Similarly they are not social animals which negates a lot of the division of labour advantages of a society. While a species of octopus might advance intellectually to ponder its own existence I doubt it could achieve the infrastructure necessary to significantly control its environment.
- Don't forget that they only live 1-2 years. 3 tops. I think this is even more limiting than fire. And if evolutionary pressure leads to longer lifespans somehow, they must overcome the whole dying after mating thing.
  
  True, also they do not raise offspring which means zero communication of non-instinctive knowledge between generations.
- They could use the underwater volcanoes to smeltle the meltle though, thought of that? Checkmate.
  
  We have terrestrial volcanoes, how far would human civilisation advanced if they were our only source of fire.

Their lifespans are very short and that whole ocean acidification thing might be a problem.
- They will evolve to have gills and walk on land
  
  Then I hope they also dump copper for iron-based blood.

Crows and ravens. Highly adaptive. At home in a deep forest or the remains of a burnt out city. Social. Predisposed to intelligence.
The whole concept of a "dominant species" is also a bit ridiculous and probably shouldn't be bought into whole cloth. If what we mean by "dominant species" is 'the most radiatively expansive single species before allopatric speciation takes over..", then pick any one of the many many invasive we've spread around the planet. Our intelligence has allowed for a massive and basically instantaneous geologic layer globally, but it's not something that can be handed off in the way that a vasculature did for land plants or the ability to decompose cellulose and lignin did for fungi.. unless we want it to be.
If you really want intelligence to make it's mark on the earth we need a way to move it from our species into other species, because we're not long for this world. Move the genes specific to human nervous tissue and neurons into bees, ants, termites, any formian creature. That'll get this party started.
- I think there's a solid argument to be made for ants as the world's dominant species. There are even supercolonies that span multiple continents. https://pmc.ncbi.nlm.nih.gov/articles/PMC3352483/
  They will likely continue to thrive in the post-human global environment. Their success does not rely on human development (like, say, rats), nor are they severely threatened by human development (like...well, most things).
  
  Was talking about this earlier with the s.o., we've both got pretty substantial biology training (phds, ms, bs etc). We both agreed that "dominant species" is a bit of a term looking for a definition, as in, it's not something extending from biology or ecology but rather something being imposed upon them. We were between nostoc and rhizobium, with fungi capable of digesting lignin in third place, for the most "world dominating" species, in the sense that those species, through their biology, have carved the planet into a place much more suited for themselves.
  It strikes me that humans aren't even really doing that, but rather, we're selecting for an environment less suitable to our own survival. So I don't know that humans would even rank for dominance over the environment because we really don't have any sense of control over the matter, whereas, some other species clearly do.

Ants. The hive mind structure will be hard to beat.
- There is no hive mind. They use chemicals to communicate.
- Ants are Fascinating

I think we will screw up this planet even more before the end. So, probably bugs.

I'd bet on racoons or some primate. They aren't going to get far though until there's enough continental subduction to reveal fresh metal and fossil fuel deposits, and that could take a very, very long time.

- I don't think any species could beat my Revolution X top score so... we kind of do dominate sweetie.
- Humans most certainly would be it by almost any intellectual qualifier you chose to use. Grading every species we have encountered with regards to intelligence and ability to control its environment humanity is a wildly insane outlier. To point of absurdity, to the point where we do not fit to such an extent that some agency other than organic evolution might be suspected.

If anyone's interested in this sort of speculative sci fi, check out A Mountain in the Sea by Ray Nayler. 10/10 world building, 9/10 science backing, 6/10 writing.

splatoon was supposed to be a warning, not a prophecy

Crabs. https://en.m.wikipedia.org/wiki/Carcinisation
Multiple different species have evolved into crabs. Apparently it's kind of a mystery.
I think they're the perfect organism.
I'm only 1/4 joking.

Crabs, everyone knows it's crabs.

My best guess? Probably another primate. Bonobos and Chimpanzees seem like the ideal candidate to take over the husk of Human civilization the quickest. Another species might have a shot, but then it's a question of how many millions of years it's going to take for them to evolve and if they can survive the cataclysmic events that will no doubt hit Earth in the meantime.
If not primates, I would bet on one of the following species:
Corvidae - Extremely intelligent, highly adaptable, tool-users, social, pass down their knowledge to offspring.
Canis Familiaris - Highly social, apex predators, genetically diverse, spread throughout every corner of the world.
Loxodonta - Extremely intelligent, highly social, adaptable, builders and tool-users, long lifespans.

Serious question:
How difficult is it for octopus to change via evolution so it becomes more like a primate?
They can already breathe on land for up to an hour.
I think they just need a few key mutations to live longer and nurture their young.
- Fun fact: octopuses* respond to MDMA, and become social and cuddly. https://www.pbs.org/newshour/science/scientists-gave-octopuses-some-molly-heres-what-happened
  I seem to recall a similar story where drug exposure reversed the octopus's usual behavior of simply waiting for death after mating, but I couldn't find a reference from a quick search so perhaps I am misremembering this story, about the biological mechanisms behind that behavior: https://www.sciencealert.com/scientists-close-in-on-why-octopuses-tragically-destroy-themselves-after-mating

I’ll bet 90% of people commenting on the internet immediately thought: “octopi!”
Twelve ponderous paragraphs into the article, this brilliant scientists finally says: “octopi.”

Interesting way to spell Daleks. EXTERMINATE!!

Crows! Oh. Are we taking guesses? Dogs! Any creatures who have lived close with humans? Cockroaches!

I would argue it depends on the method humans get removed from the equation. Chances are, humans are going to leave behind such a mess of that it’s going to be pretty hard for most things to survive.
Anything living off hydrothermal vents should be fine, even if the Earth undergoes prolonged nuclear winter or even a snowball earth scenario. Everything else is at great risk of going extinct. Tardigrades should be fine though, since they can survive all sorts of weird extremes.

Why would even be a next "dominant single species", like humans?
Out of the billions of alive organisms that had ever been on earth only humans have human intelligence. It doesn't seem like a common trait for any organism.
I think that humans are just some weird anomaly. Once we are gone there will probably not be any other intelligent species for a while, if forever.

As the documentary novel Children Of Ruin can attest to

I think they could become dominant if they acquired language. Maybe do some crazy sign language with their 8 tentacles. Also their short lifespan could be overcome if they worked together as a group or a hivemind, like the way ants do.