Are My Sci-Fi Population Estimates Realistic?

[MarcoD]

It's hard to imagine how long a time 500 million years is. 500 million years ago:

There were no people.
There were no apes.
There were no primates.
There were no vertebrates.
There were no land animals of any kind.
There was no land life of any kind.

The closest human relative then was something that resembled coral or a sponge.

About one or two supercontinents ago?

 

[Ryan_m_b]

It's hard to imagine how long a time 500 million years is. 500 million years ago:

There were no people.
There were no apes.
There were no primates.
There were no vertebrates.
There were no land animals of any kind.
There was no land life of any kind.

The closest human relative then was something that resembled coral or a sponge.

Just trying to compare human society (economically, politically, culturally, technologically etc) now to that of 500 years ago is enough to illustrate the monumental change and variety that history imposes.

Yah, I believe so too. There's no manner in which to stop evolution unless you decide so yourself by prohibiting it for some reason and move over to cloning people. There could be reasons to do so, of course, but the most natural outcome would be that the species would die at some point because of some super-flu emerging. So you would need to clone not only the species, but the whole of nature consistently.

It probably is a nice idea for a book though.

Yeah it would have to be artificial but as you aptly point out just because humans may hypothetically used technology to "halt" evolution the rest of nature would march on. Continually cloning individuals susceptible to plague is not a good idea by anyone's standards. Also if one were to use this plot device there would be the temptation for the reader to ask why the specific genotypes chosen are the only ones and why there isn't some society somewhere using the same technology to diversify.

About one or two supercontinents ago?

Try five http://en.wikipedia.org/wiki/List_of_supercontinents#Prehistoricals

 

[DaveC426913]

In a half billion years, whatever we still call humanity will not be flying around in troop ships and shooting weapons.

In a half billion years, if we're still fighting wars, if we want to go somewhere we'll simply "think" ourselves there. If we have to destroy something, we'll simply "think" it destroyed.

Think of how far our capabilities have advanced in just 150 years since the industrial revolution.

Your timeline is way too long for the sensibilities of the story you're writing. I'd shorten it by several orders of magnitude to get the human race you're looking for. Even 100 thousand years might be too long.

 

[Vanadium 50]

Continually cloning individuals susceptible to plague is not a good idea by anyone's standards

Indeed - this is why I said that having population growth limited by disease is inconsistent with slowed/stopped evolution. The sickle-cell trait mutation, for example, has evolved at least five separate times.

 

[Ryan_m_b]

In a half billion years, if we're still fighting wars, if we want to go somewhere we'll simply "think" ourselves there. If we have to destroy something, we'll simply "think" it destroyed.

Think of how far our capabilities have advanced in just 150 years since the industrial revolution.

I agree with the point but I think it is faulty logic to assert that we will be godlike at some point on the basis of past improvements.

When writing SF and choosing technology it's important to work out not only why this technology is in the setting but also what related technologies should be included because of this.

 

[MarcoD]

I agree with the point but I think it is faulty logic to assert that we will be godlike at some point on the basis of past improvements.

Is it pessimist or realist? I agree, personally I think we'll just hit some hard limits and be stuck on this ball of mud. So to me the positive scenario is sustainability until we're hit by a meteor or the sun blows up; not populating the galaxy.

 

[Ryan_m_b]

Is it pessimist or realist? I agree, personally I think we'll just hit some hard limits and be stuck on this ball of mud. So to me the positive scenario is sustainability until we're hit by a meteor or the sun blows up; not populating the galaxy.

I'm heartened by the fact that to live elsewhere we would have to figure out how to construct and maintain complex, productive ecosystems. If we can do that then we can maintain Earth's biosphere relatively easily.

This is also why the eggs-in-one-basket and we-ruined-the-planet-so-moved-elsewhere plot devices never work for me.

 

[DaveC426913]

I agree with the point but I think it is faulty logic to assert that we will be godlike at some point on the basis of past improvements.

To be clear, it is perfectly reasonable to assume this erstwhile godhood is technology-based.

To fight wars, humans are not going to want to fly their fragile little bodies into danger when they can simply make an army of machines do it for them. And they won't need clunky joysticks and computer screens to do so.

Any sufficiently advanced technology is indistinguishable from magic.

 

[Ryan_m_b]

To fight wars, humans are not going to want to fly their fragile little bodies into danger when they can simply make an army of machines do it for them. And they won't need clunky joysticks and computer screens to do so.

True, I'd find it reasonable if someone suggested that before this century is out most armies will be comprised of >50% drones.