Who will replace us?
 

If humanity would go extinct, by its own doing or by some other reason, who is most likely to replace us? I mean, what kind of animals are the ones closest to develop a high intelligence? Will it be chimansees? They are rather intelligent, they are good at manipulating things and they have started to manufacture tools. Will it perhaps be the crows. They have shown to be more intellient than earlier believed. Some of them are also even better toolmakers than the chimps. They have also a complex social behaviour.
Will it be dolphins. Maybe they are not so handy with tools, but their mental capacity is good.

And so we have the octopii. They are intelligent and rather good at manipulating objects. They are shortlived and not so social but that can shange during evolution. Some species (or groups within a species) have already been seen to be able to develop more complex social relations and increase their ability to learn from each other during environmental pressure.

so who do you think are the most likely candidate to replace us as an intelligent and/or dominating species?

Either our own machines (if we survive another few centuries) or some other ape. I don't think crows or octopi have the environment you need for tool-making. (Hands and fire, respectively.)

Cephalopods!!! Oh yes.

One attribute which makes them a real contender is that they are highly adaptable! Their tentacles work fine for gripping things, like hands (that is, in an environment of water), and they definitely have demonstrated tool use!

Edit: Sorry about the exclamations, I'm rather enthusiastic about cephalopods.

I'm kinda biased against the cephalopods, since I'm a physicist.

The COCKROACH will outlive damn near ANYTHING.

http://unseencolors.com/upload/Wall-E-Cockroach_l.jpg

?

- Mikko

Because heat, airborne toxins, biological agents,and more suprisingly radiation levels that are absolutely lethal to humans DON'T bother cockroaches.

It isn't guaranteed to happen just as there might not only be one sentient species at a time. Species don't evolve towards a specific goal; evolution doesn't work like it does in pokemon.

Sentient species, none for the foreseeable future if ever. Dominant species; again none - humans adapt to a far wider variety of environments than any other animal. Each continent or biosphere could well have a different one, but not a global one.

Actually, they sort of do - the goal is to breed most effectively. Being sentient is a massive advantage in that respect, which means that any sentient species will be able to stop another from evolving in the same area. If they then start developing tools, they can easily wipe out any other sentients across the globe, since memetics is several orders of magnitude faster than biological evolution.

You're doing it wrong - for one assuming they share the same environment; for another assuming that they hunt for reasons other than food. Outcompeting another doesn't have to be complete, and there's far less stopping, for example, sentient land-based and aquatic life.

Also, There. Is. No. Specific. Goal. To. Evolution. Species wouldn't become a humanoid reptilian/avian/plant given enough time just because, neither would a human eventually become an elf/energy being/human with whatever exaggerated characteristics. Evolution is a response to an environment, not a climb towards a programmed state - I thought you'd know that.

Environments change and if the requirements are right there can very well develop another sentient organism. In a TV-program about octopii they showed that environmental change outside Corsica led to more sociable octopii, they started to learn from each other in a higher degree than usual and they became more dominant in the environment (some of them even started to attack their arch enemies the moray eels). So if circumstances are right sentience could probably evolve again.

One can wonder how a octopii civilisation would look like.

Yes, ENVIRONMENTAL CHANGE. Not some programmed path. They won't spontaneously become sentient if given time, or in order to 'fill a gap' if other sentient species die out. That's nothing but creationist attempts to co-opt established fact.

There does not 'have' to be a sentient species. If one dies out, they won't get 'replaced' just because. Although two at once is less likely, there are still various scenarios where it could be a possibility, but they need pressures in that direction, they don't just reach some 'ideal' 'end form' given enough time.

...Was I unclear?

Although it doesn't have to be complete, I suspect that even a minor difference in intelligence conveys such a big advantage that it would be complete in practice.

I do know what you're talking about, which is why the "goal" is a criterion instead of a "perfect creature." The best breeder will win out, until it hits the limits of its food source(s). In the case of a species that can eat nigh-anything (e.g. us) that takes a very long time.

At the same time one can see the phenomena that certain kind of environments, or circumstances, many times reult in organisms that are rather like each other, or share certain traits. A classical example is fishes, ichtyosaurs and whales who share certain traits (fins, streamlined body) because they live (or lived) in similar environment. Perhaps certain conditions tend to give rise to sentience too (even if I can admitt it does not happen very often, at least not before we humans entered the scene). That makes it still interesting to speculate about what kind of creatures could evolve sentience, if the environmental conditions are right. And also which of todays creatures have most capacity to perhaps evolve sentience, at least in the foreseable future.

As it looks that in the past there were no species that reached a level of manipulating intelligence as humans do now (see the "ancient aliens" thread ;) ), I dont think it is a "niche" that has to be filled. In fact some biologists argue that it may actually be a dead end in evolution because it leads to what is now called the "sixth mass extinction". That does not say anything on other ways of intelligence. Manipulative intelligence (e.g. a form of intelligence that allows the species to completely shape their environment) may be only one form of intelligence among many possibilities. Maybe other beings memory or their ability to memorize songs or to dream may be a lot stronger.
But in terms of manipulative intelligence, I'd also be inclined to either other primates, though I give them little chance if we are talking about a human extinction scenario because that most likely would affect them as well (e.g. if climate change makes mammal life impossible in many parts, if a virus kills humans and other primates, if humanity blasts the planet with nuclear bombs). Many of these things also affect the oceans, but still aquatic life is somewhat shielded from some of the dangers (though ocean acidification, pollution, overfishing, eutrophication,... are also killing oceanic species). So I'd also give the cephalopods a fair chance - they even have good potential to actually develop the ability to go terrestrial. If extrinction event is large enough, all bets are off though - who would have thought that when the great reptiles were wiped out, that some rodent sized animals called mammals would rule the world some millions of years later. This is by the way the minimum timescale we'd be looking at in terms of this topic: millions of years...

The idea of sentient cephalopods has been explored in the fascinating BBC TV-series The Future is wild. In the series a tree dwelling cephalopod species becomes sentient 200 milion years into the future.


http://www.google.se/url?source=imgl...XzGcvy8Q9QmYhw

Squibbons, tree dwelling intelligent cephalopods.

Squibbon - Speculative Evolution Wiki

I replaced a shoe lace once