Our world, without people?

[Driddle]

It would only take a generation or two. Stray dogs around the world share the same basic morphology.

So you think that within just a generation or two, you'd see all dogs be of about the same height, weight distribution, coloration, etc? Yes, they have the same 'basic' morphology, but we've bred canines for a lot of variability. One could also expect that humans would have bred the variability out of our species, too, within a few generations. Hasn't happened yet.

Dogs living feral, however, settling into regions, with natural selection working on the best adapted? ... I'd expect at least several potential new mutt 'breeds' in the United States, and it would take longer than just two generations of litters to stabilize.

I also wonder if domesticated dogs would naturally cross back with wolves and coyotes, or maintain their own genetic lines?

 

[Tonguez]

So you think that within just a generation or two, you'd see all dogs be of about the same height, weight distribution, coloration, etc? Yes, they have the same 'basic' morphology, but we've bred canines for a lot of variability. One could also expect that humans would have bred the variability out of our species, too, within a few generations. Hasn't happened yet.

Nah I don't think it will take very long for dogs to find a middle ground - colouration may continue to vary for a few generations longer - but overall I can see all dogs going for medium height and build, short hair and the 'dingo/coyote' look

Indeed it is probably because dog breeds are so variable whilst remaining genetically identical that they will quickly revert to a common type as the various breed traits are cancelled out - afterall when a Chihuahua and Mastiff mate , the littler has just got to go middleground for the sake of sanity and all thats decent!!!

Anyway imho any future breed variation will occur because of crossbreeding with other canines (eg Wolf) or in uniquely isolated populations (which might occur on an island but not on the mainland)

 

[Utrecht]

To give you an idea of roads - the interstate highway system came to be in the Eisenhower years. Note that mere decades later it is in constant need of repairs. Signs of the roads may be visible centuries later, but it won't be much of a road after a few decades (again, assuming temperate, climes with moderate rainfall).

On the flip side - Roman roads are still in great shape today - so alot has to do with the quality of manterials and constructions - after all, the Roman Legionairre never had to deal with Lowest Bid Contractors

 

[mmadsen]

So you think that within just a generation or two, you'd see all dogs be of about the same height, weight distribution, coloration, etc?

Yes.

Yes, they have the same 'basic' morphology, but we've bred canines for a lot of variability.

Yes, we have bred canines for a lot of variability -- but almost all of that variability disappears with just a little crossbreeding.

One could also expect that humans would have bred the variability out of our species, too, within a few generations. Hasn't happened yet.

Two points. First, humans haven't crossbred across (existing) racial lines in large amounts for many generations yet. Those humans of mixed ancestry don't typically look distinctly European, or African, or Asian, or whatever; many distinctive traits tend to disappear with a little genetic shuffling. Second, I'm not suggesting that all variation within the species will disappear -- far from it! -- just the distinctive variation of artificial breeds.

Dogs living feral, however, settling into regions, with natural selection working on the best adapted? ... I'd expect at least several potential new mutt 'breeds' in the United States, and it would take longer than just two generations of litters to stabilize.

Around the world, stray dogs are medium-sized, vaguely brown mutts.

 

[DMScott]

Let's say that for some reason (we'll discuss that later), every person on the planet suddenly disappeared. Gone from the world. No more people, anywhere. ... Further, all dressings of society were left in place exactly as they are now, without first being tidied or deconstructed.

OK, but note that the 'why' question will have a big effect on the answer to 'what happens'.

What would be left of those remnants left to nature after 1,000 years? After 10,000 years? After 100,000 years?

In a typical temperate environment, some large well-built structures will probably be around at 1000 years, but most of the smaller stuff will be rubble long before that. You probably won't even be able to tell where most of the cleared land once existed. Best odds for something being preserved are in deserts, and even there wind erosion would probably take it's toll.

At 10000 years, you'd probably have to do archaeological digs to find evidence of humanity. At 100000, even that will only turn up fossils.

For example: Would houses still be standing if there were no one left to control fires caused by lightning storms? How much damage would trees cause to structures without anyone around to keep them pruned away? Would any of them still be secure from wild animals years and years from now?

Fire would only be a factor for a few centuries, I imagine - plant growth would probably be the major cause of destruction. Trees wouldn't be the main worry, grasses, lichens, creepers, vines, etc. would be the first to move in to a settled area. Trees would come in once some soil started to be uncovered.

The only structure that might be secure after 1000 years would be something specifically designed to avoid environmental damage - for example, an underground bunker of some kind. Best to place it somewhere like the Canadian Shield where there's unlikely to be much tectonic activity.

Or what about transportation -- How long does it take for vegetation and weather to wear away an entire stretch of Interstate? What would become of our vehicles?

Vehicles likely wouldn't last a century - well, maybe the ones with plastic bodies would still be recognizable, but by 1000 years they'd be buried. I doubt the road network would outlast cars by more than a couple centuries, though maybe some bridges and such would still be recognizable in 1000 years.

And wildlife? Hoo-boy ... Which species would take over the landscape without people to get in the way?

We're currently living in one of the great die-offs, particularly among large mammals which have seen species go extinct at a frightening pace for around 50000 years (three guesses what's killing them). So if humanity goes, there's suddenly a huge number of niches just waiting for something to fill them. Gould's big idea, punctuated equilibrium, holds that such an environment would be perfect for a burst of new speciation. Maybe even new families. Imagining what those might be is a matter of pure speculation, but a paleobiologist named Michael Boulter (author of "Extinction: Evolution and the End of Man") is putting his money on small mammals (assuming they're not wiped by the same thing that takes out humanity), birds, and insects.

At 1000 years, you'd probably just see a lot of species expanding into the new environments. At 10000 years, probably a few early attempts at adaptation - predators get bigger, creatures adapt to new climates, that sort of thing. 100000 years is probably where you'd find the weird stuff.

 

[Ashrem Bayle]

I've often toyed with this idea as part of a campaign. I think it would be interesting to take Urban Arcana in this direction. Remove 99% of the population and advance time about 20 years.

The remians of mankind "awake" to find their world deserted. Monsters now exist in the shadows, and magic/psionics has re-emerged. Problem is, I can't think of a reason for this to happen.

 

[Sir Whiskers]

Let's assume that there's some kind of Marie Celeste effect: People simply vanish, leaving everything as it is right at this second. For simplicity's sake, we'll assume that at that second, there are no cars, busses, planes, trains, whatever in motion at the time.

This assumption is why logically I prefer something a bit slower, say a world-wide plague or whatever.

If everyone disappears at once, you will have all those auto's, planes, etc. moving around. You'll also have lots of suddenly unattended equipment. Most importantly, you have active nuclear reactors which will have only automated equipment to keep them from melting down - anyone have an idea what would happen with them?

If, OTOH, the world's human population dies out within a few months or even years, most of these problems will be avoided. You will also have some groups attempting to avoid this fate, perhaps by sealing themselves in fallout shelters and the like. Maybe even some massive government projects. Lots of stuff for the characters to discover when they show up on Earth.

BTW, it just occurred to me. In the timeframes we're discussing, I would think nothing would still be orbiting the Earth. Satellites seem to only stay up there for a few years (couple decades at most?), so people returning to the planet wouldn't find anything in orbit. Kind of off-topic - oh well...

 

[DMScott]

I've often toyed with this idea as part of a campaign. I think it would be interesting to take Urban Arcana in this direction. Remove 99% of the population and advance time about 20 years.

The remians of mankind "awake" to find their world deserted. Monsters now exist in the shadows, and magic/psionics has re-emerged. Problem is, I can't think of a reason for this to happen.

If you're having magic/psionics re-emerge, why not just link the explanation to that? The return of psionics drives 99% of the people suicidally insane, or some big magical event kills a huge number of people.

But if you really want a "natural" explanation:

- bioweapons getting out of control works. A strain of ebola that spreads as easily as the flu gets loose at JFK airport just before Christmas, that sort of thing.

- climate change might work. The worst-case global warming scenarios have the gulf stream changing course or stopping for a while, which would likely trigger an ice age in North America and Europe. Panic migration south, critical food shortages, sudden overpopulation in equatorial zones, not enough fresh water, etc.

- visitor from space. Drop a big enough comet/meteor/whatever in the middle of the Pacific, and you can wipe almost everybody.

The real problem is making sure some people survive. Maybe have an underground bunker with some kind of suspended animation technology, a la Aftermath.

 

[mmadsen]

But if you really want a "natural" explanation:

- bioweapons getting out of control works. A strain of ebola that spreads as easily as the flu gets loose at JFK airport just before Christmas, that sort of thing.
[...]
The real problem is making sure some people survive.

Actually, some fraction of the population will survive just about any disease. Ebola's lethality rate isn't 100 percent; it's only 70% to 85% or so (depending on what source you cite).

 

[kenjib]

I vaguely remember reading somewhere once, a long time ago, a supposition that without automobile traffic to thin the herd, the armadillo population would make huge advances in North America.

Even with automobile traffic, their range is spreading very quickly right now. I've heard a projection that they are eventually going to spread to as far north as Washington state and south canada on the west coast and also pretty far up the rest of the US. I remember it was within my lifetime but I don't remember how long. I also can't recall the source, so grain of salt and all that...