If all humans on earth died out from a deadly plague, which species is most likely to take over the role us Homo sapiens left behind? Which species is intelligent enough to build their own civilization?
No species is intelligent enough to build its own human-like civilization. If all humans died out the world would slowly revert back to the wilderness from which it came. Many different species of wild animals would proliferate into the habitats left by man but none of them would “replace” man at least not in the short term.
Over millions of years it is a matter of opinion what would happen. It might be that history would repeat itself and one of the great ape species might evolve along similar lines that we did. It is also entirely possible that this would not happen at all as conditions now are different from those when Homo Sapiens first evolved.
Here's a dark horse candidate for you: raccoons.
In a study by the ethologist H. B. Davis in 1908, raccoons were able to open 11 of 13 complex locks in fewer than 10 tries and had no problems repeating the action when the locks were rearranged or turned upside down. Davis concluded they understood the abstract principles of the locking mechanisms and their learning speed was equivalent to that of rhesus macaques.
Studies in 1963, 1973, 1975 and 1992 concentrated on raccoon memory showed they can remember the solutions to tasks for up to three years. In a study by B. Pohl in 1992, raccoons were able to instantly differentiate between identical and different symbols three years after the short initial learning phase.
have a neuron count rivalling primates (admittedly the connection between neuron count and intelligence isn't proven, but it's unusual for a non-primate of its size);
Within the raccoon’s cat-sized brain lurks a doglike number of neurons. So many, in fact, that if you were to look only at neuron count and brain size, you might mistake the raccoon for a small primate.
and they are, of course, quite skilled with their hand-like paws.
There are a number of species with the potential to redevelop civilization in a post-human world. I like the idea of cephalopods taking over, but as Slarty points out, it is just as likely that apes could take over again (humans are a species of ape). The species would need problem-solving intelligence, an ability to communicate complex ideas, and the dexterity required for toolmaking and construction. Offhand, the only species I can think of with all of these requirements would be cephalopods, apes, and maybe elephants, though I am sure there are probably plenty of others.
How about ants?
In Bernard Werber's The Ants, there is an extract where a fictionnal writer says that if an extraterrastrial lifeform would arrive on Earth, it would seek contact with ants before humans.
Think about it:
- auto-management of an habitat for a whole colony
- communication and heavy teamwork
- population control (soldiers, workers,...)
Of course The Ants is a work of fiction, but hey, we are worldbuilding here!
Wikipedia defines a civilization as a "complex society characterized by urban development, social stratification imposed by a cultural elite, symbolic systems of communication (for example, writing systems), and a perceived separation from and domination over the natural environment."
No other species on earth is intelligent enough to form a civilization. Significant evolutionary changes would be needed for any other species to be able to do so. Such changes would be distinct enough to be considered a separate species. What species another intelligent lifeform will evolve from is entirely different question.
The only candidates lies with the great apes
The only potential there is, is that some of the other great apes develop intelligence. To me, this seems very unlikely to happen before the sun burns out the Earth's atmosphere, even as advanced as they are today.
My guess is that it might be possible for Bonobos, but I don't think it's remotely likely to happen. Chimpanzees is a close second, but the aggression they exhibit might be a hindrance. I can't think of any other species that would stand a chance.
If any species is to evolve into human like intelligence, there must be some evolutionary force(*) that drives that intelligence. I'm not familiar with any force that will do so, but clearly, at least one such force exists, or we wouldn't be here discussing it.
In order for a civilization to appear, you must have more than just intelligence; you also need to be able to make tools and meta-tools -- that is, you must be able to make tools that you use to make other tools. This requires dexterity that only apes possess at the moment; this alone bars all other species from developing any kind of civilization. Curiously, many great apes already make tools, including orangutans who use spears for fishing.
(*) This is not meant to be understood as some physical force of any kind. Merely some sort of mechanism that requires the development of higher-order intelligence.
Empire of the Rats!
Ok, The common rat is a mammal that has adapted to nearly as many environments as homo sapiens. They are reasonably smart. All they need is a small boost in brains and opposable thumbs and they could be lords of creation.
Rats have followed humanity all over the planet and we are always hard pressed to get rid of them. They get to wherever we go and then adapt to their environment, often thriving. This adaptability to a variety of places is the key.
Humans, unlike our cousins the great apes, have expanded and adapted to different environments. Most of the other great apes have stayed in a specific range.
Rats might not be objectively as smart as some other animals, but they are extremely adaptive, and that will give them a better chance to evolve up to, then past ape level intelligence.
Rats also get one final edge....NIMH! (sorry, couldn't help myself)
The answer is simple. Any species is capable. The real question is how long do you want to wait?
Of course after waiting millions of years (or longer), chances are the new species won't actually look anything like the original species. Whales evolved from a land based wolf like creature over the last fifty million years.
Humans did not start out super intelligent and "civilized." The proto of all mammals - including us - is thought to be a small, shrew like animal. From shrew to ape to man took hundreds of millions of years, and untold variations of hominids in between.
Consider that in all these millions of years, our great ape relatives (gorillas, chimps and orangutans) remained virtually the same. Therefore, I don't think apes are going to evolve significantly enough to take up where humans left off, before they go extinct.
What's more likely is that some really outrageous or catastrophic thing is going to happen on this Earth AGAIN, and this will jumpstart another extant species into evolving into beings with intelligence and abilities comparable to humans.
Whoever the "lucky" inheritors turn out to be, I hope the new smart guys will be much smarter than we were. They won't plunder the planet for petroleum, or despoil it with plastics, or rob their very air of oxygen with fumes from cars and factories, or by cutting down the world's trees.
There are plenty of possibilities, providing that we are not too strict with our definition of 'civilization'. Generally, I would consider tool-making, social structuring and a mechanism for knowledge transfer, to be essential. Beyond this, recognisable buildings and structures (although networked tunnel systems could count) and language (especially written) would seem to be reasonable requirements.
Wikipedia includes "a perceived separation from and domination over the natural environment", but this is largely subjective and it could be argued that simply developing and maintaining living areas would satisfy this.
Tool-making requires some manual dexterity, so the species would need some capacity for this - this tends to rule out fish, whales and dolphins (without significant evolution)
Obviously primates, also rodents and many birds, possibly also cephalopods - all of these are reasonably intelligent and dexterous.
However, another requirement, I think, for what we might recognise as a civilization is a reasonable longevity, within which knowledge can not only be acquired over time, but also passed on (first by word of mouth, later through written language). It could be expected that the process of knowledge transfer, and the need for it, would in time produce some kind of written language, but this too would require further learning and tuition and therefore time. Longevity is therefore essential, as is the ability to develop an aural tradition.
Rodents and cephalopods are not particularly long-lived at present.
Taking life-span into account as a key criteria, the best candidate would seem to be a species of parrot. Parrots already have complex social structures. Note also, that parrots, like many birds already build their own dwellings (nests) and in particular the Monk Parakeet actually builds large communal nests on occasion. Parrots have also shown facility with human language, and the capacity to develop their own.
How exactly a parrot would evolve over time, though, I haven't worked out. I just think they are the best candidate for knowledge acquisition and transfer and, therefore, the handing down across generations of a civilization and they seem already to have many of the other necessary skills.
This is just an assumption, but I believe that in the event of a mass extinction of humans, animals as we know them will tend to disappear as well. But excluding the hypothesis that what will "kill" humans kill all living beings, I think that exploiting oil and nuclear weapons, for example, with a lack of human maintenance will have repercussions on animal life.
So for me, if there is anything that will build a civilization, more or less like ours, it still does not exist and will evolve from the conditions that come to exist.
Sorry for my English, I know it's not perfect at all :)
"Which species is most likely to take over the role us Homo sapiens life behind?"
Let's assume the plague you mention is only capable of infecting humans and is able to spread quickly enough to infect all humans before killing them. If humans start dying en mass then this will cause problems for every living thing on earth as well.
With mass extinction, panic is going to spread quickly and the typical breaking down of civil society will cause riots, looting, and general anarchism as people try to do whatever they can to survive which is likely to cause things like fires which on a mass scale could linger for quite some time since nobody would be keeping them in check.
Most people would probably assume that first point, but one idea I had if humans died is all of the manual tasks in place to keep things like nuclear reactors in check. Without human intervention on many processes you will see things like nuclear reactors going critical because of insufficient cooling which will completely destabilize an environment and kill of large areas. I'm sure the military arsenal of nuclear weapons need some kind of maintenance as well although I am unsure to what degree and if they would also be likely to explode as well in which case we have an even larger problem. Aside from radiation you would have to account for environmental disasters that would spawn from large fires, nuclear, etc. Depending on the severity, you could see large portions of the earth in darkness due to smoke which could cause temperatures to drop. (This is conjecture of course since we don't have much knowledge on mass nuclear breaches)
I think the imprint we have on the world is too much for us to leave or all die off without causing a crippling blow to other creatures on the earth as well. This is not to imply that all life would cease as this is very unlikely to kill less populated areas such as deep jungle and aquatic creatures.
I will assume you are giving an infinite amount of time for evolution to take place in which case nobody truly knows what will rise up or how creatures will evolve. Aquatic creatures would likely reign supreme as all of the fallout on land and rising sea levels. By the time they would be evolved enough to come back to land, there would likely be little no evidence of human structures left as this would require millions and millions of years.
"Which species is intelligent enough to build their own civilization?"
The creatures with the largest brains in the least populated environments would be the most likely (After millions and millions of years to completely change to how we recognize them today). Apes, Dolphins, and other mammals are easy choices, but who really knows after such a long time if they would not die out to some other disaster or some new creature become the apex predator and eventually evolve and start it's own civilization.
For another creature to take over the role of homo sapiens, you need to define the role of homo sapiens.
What creature could cultivate crops for more food, build cities, create governments, start wars, raise taxes, quarrel over differences in appearance, initiate the concept of freedom of speech and then restrict it with political correctness, invent fertilizer for crops and then turn it into explosives, create flying machines and destroy cities with them, refine information transfer and transfer rubbish with the result, and worship the Kardashians?
It's not so much a question of finding a creature capable of that, but one willing to stoop that low.